Enzymes that catalyze the interconversion of aldose and ketose compounds.
A five-carbon sugar alcohol derived from XYLOSE by reduction of the carbonyl group. It is as sweet as sucrose and used as a noncariogenic sweetener.
An enzyme that plays a role in the PENTOSES and GLUCURONATES interconversion pathway by catalyzing the oxidation of XYLITOL to D-xylulose. This enzyme has been found to be specific for NAD+.
The decarboxylation product of UDPglucuronic acid, which is used for formation of the xylosides of seryl hydroxyl groups in mucoprotein synthesis. Also forms plant xylans.
Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.
An enzyme that catalyzes reversibly the oxidation of an aldose to an alditol. It possesses broad specificity for many aldoses. EC 1.1.1.21.
Polysaccharides consisting of xylose units.
Enzymes that catalyze the epimerization of chiral centers within carbohydrates or their derivatives. EC 5.1.3.
A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC 3.2.1.8 catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC 3.2.1.32 catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC 3.2.1.37 catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC 3.2.1.72 catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds.
A class of carbohydrates that contains five carbon atoms.
Directed modification of the gene complement of a living organism by such techniques as altering the DNA, substituting genetic material by means of a virus, transplanting whole nuclei, transplanting cell hybrids, etc.
Enzymes which catalyze the endohydrolysis of 1,4-beta-D-xylosidic linkages in XYLANS.
A disaccharide consisting of two glucose units in beta (1-4) glycosidic linkage. Obtained from the partial hydrolysis of cellulose.
The study, utilization, and manipulation of those microorganisms capable of economically producing desirable substances or changes in substances, and the control of undesirable microorganisms.
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that is not known to be pathogenic for man, animals, or plants. Its organisms are spoilers for beers and ciders and in sweet English ciders they are the causative agents of a secondary fermentation known as "cider sickness." The species Z. mobilis is used for experiments in molecular genetic studies.
A clear, colorless liquid rapidly absorbed from the gastrointestinal tract and distributed throughout the body. It has bactericidal activity and is used often as a topical disinfectant. It is widely used as a solvent and preservative in pharmaceutical preparations as well as serving as the primary ingredient in ALCOHOLIC BEVERAGES.
A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.
A xylosidase that catalyses the random hydrolysis of 1,3-beta-D-xylosidic linkages in 1,3-beta-D-xylans.
Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.
Process by which micro-organisms adapt quickly to a preferred rapidly-metabolizable intermediate through the inhibition or repression of genes related to CATABOLISM of less preferred source(s).
A genus of yeast-like mitosporic Saccharomycetales fungi characterized by producing yeast cells, mycelia, pseudomycelia, and blastophores. It is commonly part of the normal flora of the skin, mouth, intestinal tract, and vagina, but can cause a variety of infections, including CANDIDIASIS; ONYCHOMYCOSIS; vulvovaginal candidiasis (CANDIDIASIS, VULVOVAGINAL), and thrush (see CANDIDIASIS, ORAL). (From Dorland, 28th ed)
A pentose active in biological systems usually in its D-form.
Methods and techniques used to genetically modify cells' biosynthetic product output and develop conditions for growing the cells as BIOREACTORS.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
A genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. Its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. Pathogenicity from this genus is rare.
An enzyme that catalyzes the synthesis of fructose-6-phosphate plus GLUTAMINE from GLUTAMATE plus glucosamine-6-phosphate.
An oxidative decarboxylation process that converts GLUCOSE-6-PHOSPHATE to D-ribose-5-phosphate via 6-phosphogluconate. The pentose product is used in the biosynthesis of NUCLEIC ACIDS. The generated energy is stored in the form of NADPH. This pathway is prominent in tissues which are active in the synthesis of FATTY ACIDS and STEROIDS.
A 5-carbon keto sugar.
Organic silicon derivatives used to characterize hydroxysteroids, nucleosides, and related compounds. Trimethylsilyl esters of amino acids are used in peptide synthesis.
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Agencies of the FEDERAL GOVERNMENT of the United States.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.

Tropical enteropathy in Rhodesia. (1/859)

Tropical enteropathy, which may be related to tropical sprue, has been described in many developing countries including parts of Africa. The jejunal changes of enteropathy are seen in Rhodesians of all social and racial categories. Xylose excretion, however, is related to socioeconomic status, but not race. Upper socioeconomic Africans and Europeans excrete significantly more xylose than lower socioeconomic Africans. Vitamin B12 and fat absorption are normal, suggesting predominant involvement of the proximal small intestine. Tropical enteropathy in Rhodesia is similar to that seen in Nigeria but is associated with less malabsorption than is found in the Caribbean, the Indian subcontinent, and South East Asia. The possible aetiological factors are discussed. It is postulated that the lighter exposure of upper class Africans and Europeans to repeated gastrointestinal infections may accound for their superior xylose absorption compared with Africans of low socioeconomic circumstances. It is further suggested that the milder enteropathy seen in Africa may be explained by a lower prevalence of acute gastroenteritis than in experienced elsewhere in the tropics.  (+info)

Uridine diphosphate xylosyltransferase activity in cartilage from manganese-deficient chicks. (2/859)

The glycosaminoglycan content of cartilage is decreased in manganese deficiency in the chick (perosis). The activity of xylosyltransferase, the first enzyme in the biosynthetic pathway of sulphated glycosaminoglycans, was studied in the epiphysial cartilage of 4-week-old chicks which had been maintained since hatching on a manganese-deficient diet. Enzymic activity was measured by the incorporation of [14C]xylose from UDP-[14C]xylose into trichloroacetic acid precipitates. Optimal conditions for the xylosyltransferase assay were established and shown to be the same for both control and manganese-deficient cartilage. Assay of the enzyme by using an exogenous xylose acceptor showed no difference in xylosyltransferase activity between control and manganese-deficient tissue. Further, the extent of xylose incorporation was greater in manganese-deficient than in control cartilage preparations, suggesting an increase in xylose-acceptor sites on the endogenous acceptor protein in the deficient cartilage. 35S turnover in the manganese-deficient cartilage was also increased. The data suggest that the decreased glycosaminoglycan content in manganese-deficient cartilage is due to decreased xylosylation of the acceptor protein plus increased degradation of glycosaminoglycan.  (+info)

Purification and some chemical properties of 30 kDa Ginkgo biloba glycoprotein, which reacts with antiserum against beta 1-->2 xylose-containing N-glycans. (3/859)

From the seeds of Ginkgo biloba, a glycoprotein, which is a major component that reacts with an antiserum against beta 1-->2 xylose-containing N-glycans, has been purified and characterized. The N-terminal amino acid sequence of the purified glycoprotein was H-K-A-N-X-V-T-V-A-F-V-M-T-Q-H-L-L-F-G-Q-. The molecular mass was estimated to be 17 kDa and 16 kDa by SDS-PAGE under reducing conditions, however, the molecular mass of this glycoprotein in the native state was 30,762 by MALDI-TOF MS, suggesting that this glycoprotein consists of two subunits; one is glycosylated and the other is not. The structure of N-glycan linked to this glycoprotein (designated 30 kDa GBGP) was identified as Man3Fuc1Xyl1GlcNAc2, which is the predominant N-glycan linked to the storage glycoproteins in the same seeds (Kimura, Y et al. (1998) Biosci. Biotechnol. Biochem. 62, 253-261). From the peptic digest of the carboxymethylated glycosylated subunit, one glycopeptide was purified by RP-HPLC and the amino acid sequence was identified as H-K-A-N-N(Man3Fuc1Xyl1Glc-NAc2)-V-T-V-A-F, which corresponded to the N-terminal amino acid sequence.  (+info)

A mutated PtsG, the glucose transporter, allows uptake of D-ribose. (4/859)

Mutations arose from an Escherichia coli strain defective in the high (Rbs/ribose) and low (Als/allose and Xyl/xylose) affinity D-ribose transporters, which allow cells to grow on D-ribose. Genetic tagging and mapping of the mutations revealed that two loci in the E. coli linkage map are involved in creating a novel ribose transport mechanism. One mutation was found in ptsG, the glucose-specific transporter of phosphoenolpyruvate:carbohydrate phosphotransferase system and the other in mlc, recently reported to be involved in the regulation of ptsG. Five different mutations in ptsG were characterized, whose growth on D-ribose medium was about 80% that of the high affinity system (Rbs+). Two of them were found in the predicted periplasmic loops, whereas three others are in the transmembrane region. Ribose uptakes in the mutants, competitively inhibited by D-glucose, D-xylose, or D-allose, were much lower than that of the high affinity transporter but higher than those of the Als and Xyl systems. Further analyses of the mutants revealed that the rbsK (ribokinase) and rbsD (function unknown) genes are involved in the ribose transport through PtsG, indicating that the phosphorylation of ribose is not mediated by PtsG and that some unknown metabolic function mediated by RbsD is required. It was also found that D-xylose, another sugar not involved in phosphorylation, was efficiently transported through the wild-type or mutant PtsG in mlc-negative background. The efficiencies of xylose and glucose transports are variable in the PtsG mutants, depending on their locations, either in the periplasm or in the membrane. In an extreme case of the transmembrane change (I283T), xylose transport is virtually abolished, indicating that the residue is directly involved in determining sugar specificity. We propose that there are at least two domains for substrate specificity in PtsG with slightly altered recognition properties.  (+info)

Factors affecting counteraction by methylamines of urea effects on aldose reductase. (5/859)

The concentration of urea in renal medullary cells is high enough to affect enzymes seriously by reducing Vmax or raising Km, yet the cells survive and function. The usual explanation is that the methylamines found in the renal medulla, namely glycerophosphocholine and betaine, have actions opposite to those of urea and thus counteract its effects. However, urea and methylamines have the similar (not counteracting) effects of reducing both the Km and Vmax of aldose reductase (EC 1.1.1.21), an enzyme whose function is important in renal medullas. Therefore, we examined factors that might determine whether counteraction occurs, namely different combinations of assay conditions (pH and salt concentration), methylamines (glycerophosphocholine, betaine, and trimethylamine N-oxide), substrates (DL-glyceraldehyde and D-xylose), and a mutation in recombinant aldose reductase protein (C298A). We find that Vmax of both wild-type and C298A mutant generally is reduced by urea and/or the methylamines. However, the effects on Km are much more complex, varying widely with the combination of conditions. At one extreme, we find a reduction of Km of wild-type enzyme by urea and/or methylamines that is partially additive, whereas at the other extreme we find that urea raises Km for D-xylose of the C298A mutant, betaine lowers the Km, and the two counteract in a classical fashion so that at a 2:1 molar ratio of betaine to urea there is no net effect. We conclude that counteraction of urea effects on enzymes by methylamines can depend on ion concentration, pH, the specific methylamine and substrate, and identity of even a single amino acid in the enzyme.  (+info)

Mutations in catabolite control protein CcpA separating growth effects from catabolite repression. (6/859)

Carbon catabolite repression in Bacillus megaterium is mediated by the transcriptional regulator CcpA. A chromosomal deletion of ccpA eliminates catabolite repression and reduces the growth rate on glucose. We describe four single-amino-acid mutations in CcpA which separate the growth effect from catabolite repression, suggesting distinct regulatory pathways for these phenotypes.  (+info)

Transport and utilization of hexoses and pentoses in the halotolerant yeast Debaryomyces hansenii. (7/859)

Debaryomyces hansenii is a yeast species that is known for its halotolerance. This organism has seldom been mentioned as a pentose consumer. In the present work, a strain of this species was investigated with respect to the utilization of pentoses and hexoses in mixtures and as single carbon sources. Growth parameters were calculated for batch aerobic cultures containing pentoses, hexoses, and mixtures of both types of sugars. Growth on pentoses was slower than growth on hexoses, but the values obtained for biomass yields were very similar with the two types of sugars. Furthermore, when mixtures of two sugars were used, a preference for one carbon source did not inhibit consumption of the other. Glucose and xylose were transported by cells grown on glucose via a specific low-affinity facilitated diffusion system. Cells derepressed by growth on xylose had two distinct high-affinity transport systems for glucose and xylose. The sensitivity of labeled glucose and xylose transport to dissipation of the transmembrane proton gradient by the protonophore carbonyl cyanide m-chlorophenylhydrazone allowed us to consider these transport systems as proton symports, although the cells displayed sugar-associated proton uptake exclusively in the presence of NaCl or KCl. When the V(max) values of transport systems for glucose and xylose were compared with glucose- and xylose-specific consumption rates during growth on either sugar, it appeared that transport did not limit the growth rate.  (+info)

The essential Staphylococcus aureus gene fmhB is involved in the first step of peptidoglycan pentaglycine interpeptide formation. (8/859)

The factor catalyzing the first step in the synthesis of the characteristic pentaglycine interpeptide in Staphylococcus aureus peptidoglycan was found to be encoded by the essential gene fmhB. We have analyzed murein composition and structure synthesized when fmhB expression is reduced. The endogenous fmhB promoter was substituted with the xylose regulon from Staphylococcus xylosus, which allowed glucose-controlled repression of fmhB transcription. Repression of fmhB reduced growth and triggered a drastic accumulation of uncrosslinked, unmodified muropeptide monomer precursors at the expense of the oligomeric fraction, leading to a substantial decrease in overall peptidoglycan crosslinking. The composition of the predominant muropeptide was confirmed by MS to be N-acetylglucosamine-(beta-1,4)-N-acetylmuramic acid(-L-Ala-D-iGln-L-Lys-D-Ala-D-Ala), proving that FmhB is involved in the attachment of the first glycine to the pentaglycine interpeptide. This interpeptide plays an important role in crosslinking and stability of the S. aureus cell wall, acts as an anchor for cell wall-associated proteins, determinants of pathogenicity, and is essential for the expression of methicillin resistance. Any shortening of the pentaglycine side chain reduces or even abolishes methicillin resistance, as occurred with fmhB repression. Because of its key role FmhB is a potential target for novel antibacterial agents that could control the threat of emerging multiresistant S. aureus.  (+info)

We investigated the control exercised by the transport over the specific xylose utilization rate in two recombinant S. cerevisiae strains, one with low XR activity, TMB3001, and one with high XR activity, TMB3260. The strains were grown in aerobic sugar-limited chemostat and the specific xylose uptake rate was modulated by changing the xylose concentration in the feed, which allowed determination of the flux response coefficients. Separate measurements of xylose transport kinetics allowed determination of the elasticity coefficients of transport with respect to extracellular xylose concentration. The flux control coefficient, C, for the xylose transport was calculated from the response and elasticity coefficients. The value of C for both strains was found to be , 0.1 at extracellular xylose concentrations , 7.5 g L-1. However, for strain TMB3260 the flux control coefficient was higher than 0.5 at xylose concentrations , 0.6 g L-1, while C stayed below 0.2 for strain TMB3001 irrespective of ...
Efficient xylose utilisation by microorganisms is of importance to the lignocellulose fermentation industry. The aim of this work was to develop constitutive catabolite repression mutants in a xylose-utilising recombinant Saccharomyces cerevisiae strain and evaluate the differences in xylose consumption under fermentation conditions. S. cerevisiae YUSM was constitutively catabolite repressed through specific disruptions within the MIG1 gene. The strains were grown aerobically in synthetic complete medium with xylose as the sole carbon source. Constitutive catabolite repressed strain YCR17 grew four-fold better on xylose in aerobic conditions than the control strain YUSM. Anaerobic batch fermentation in minimal medium with glucose-xylose mixtures and N-limited chemostats with varying sugar concentrations were performed. Sugar utilisation and metabolite production during fermentation were monitored. YCR17 exhibited a faster xylose consumption rate than YUSM under high glucose conditions in ...
We have recently demonstrated that heterologous expression of a bacterial xylose isomerase gene (xylA) of Burkholderia cenocepacia enabled a laboratorial Saccharomyces cerevisiae strain to ferment xylose anaerobically, without xylitol accumulation. However, the recombinant yeast fermented xylose slowly. In this study, an evolutionary engineering strategy was applied to improve xylose fermentation by the xylA-expressing yeast strain, which involved sequential batch cultivation on xylose. The resulting yeast strain co-fermented glucose and xylose rapidly and almost simultaneously, exhibiting improved ethanol production and productivity. It was also observed that when cells were grown in a medium containing higher glucose concentrations before being transferred to fermentation medium, higher rates of xylose consumption and ethanol production were obtained, demonstrating that xylose utilization was not regulated by catabolic repression. Results obtained by qPCR demonstrate that the efficiency in xylose
The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivations on single carbon sources, it was demonstrated that xylose acted as a carbon catabolite repressor (xylose cultivations), while the enzymes in the xylose utilisation pathway were also subject to repression in the presence of glucose (glucose cultivations). In the wild type strain growing on the sugar mixture, glucose repression of xylose utilisation was observed; with xylose utilisation occurring only after glucose was depleted. This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. Measurement of key metabolites and the activities of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA ...
article{0c9c6596-022a-424f-a1a1-682387e3dd78, abstract = {Disruption of the ZWF1 gene encoding glucose-6-phosphate dehydrogenase (G6PDH) has been shown to reduce the xylitol yield and the xylose consumption in the xylose-utilizing recombinant Saccharomyces cerevisiae strain TMB3255. In the present investigation we have studied the influence of different production levels of G6PDH on xylose fermentation. We used a synthetic promoter library and the copper-regulated CUP1 promoter to generate G6PDH-activities between 0% and 179% of the wild-type level. G6PDH-activities of 1% and 6% of the wild-type level resulted in 2.8- and 5.1-fold increase in specific xylose consumption, respectively, compared with the ZWF1-disrupted strain. Both strains exhibited decreased xylitol yields (0.13 and 0.19 g/g xylose) and enhanced ethanol yields (0.36 and 0.34 g/g xylose) compared with the control strain TMB3001 (0.29 g xylitol/g xylose, 0.31 g ethanol/g xylose). Cytoplasmic transhydrogenase (TH) from Azotobacter ...
Bioethanol production from lignocellulosic biomass, in particular xylose, is currently of great concern, given the abundance of this sugar in the world, because Saccharomyces cerevisiae, which is widely used for bioethanol production, is unable to naturally ferment xylose. The aim of this study was to obtain a novel yeast capable of stably producing ethanol from biomass containing xylose by protoplast fusion between S. cerevisiae and xylose-utilizing yeast. We describe a novel xylose-fermenting yeast strain, FSC1, developed for ethanol production by intergeneric hybridization between S. cerevisiae and Candida intermedia mutants by using a protoplast fusion technique. The characteristics of the FSC1 strain are reported with respect to xylose fermentation, morphology, gene, and protein expression. Mutation of the parental strains prior to protoplast fusion endowed the FSC1 strain with the ability to convert xylose to ethanol. Microscopic analysis confirmed that the parental and FSC1 strains produced
Engineered strains of Saccharomyces cerevisiae have significantly improved the prospects of biorefinery by improving the bioconversion yields in lignocellulosic bioethanol production and expanding the product profiles to include advanced biofuels and chemicals. However, the lignocellulosic biorefinery concept has not been fully applied using engineered strains in which either xylose utilization or advanced biofuel/chemical production pathways have been upgraded separately. Specifically, high-performance xylose-fermenting strains have rarely been employed as advanced biofuel and chemical production platforms and require further engineering to expand their product profiles. In this study, we refactored a high-performance xylose-fermenting S. cerevisiae that could potentially serve as a platform strain for advanced biofuels and biochemical production. Through combinatorial CRISPR-Cas9-mediated rational and evolutionary engineering, we obtained a newly refactored isomerase-based xylose-fermenting strain,
Saccharomyces cerevisiae ferments hexoses efficiently but is unable to ferment xylose. When the bacterial enzyme xylose isomerase (XI) from Thermus thermophilus was produced in S. cerevisiae, xylose utilization and ethanol formation were demonstrated. In addition, xylitol and acetate were formed. An unspecific aldose reductase (AR) capable of reducing xylose to xylitol has been identified inS. cerevisiae. The GRE3gene, encoding the AR enzyme, was deleted in S.cerevisiae CEN.PK2-1C, yielding YUSM1009a. XI fromT. thermophilus was produced, and endogenous xylulokinase from S.cerevisiae was overproduced in S.cerevisiae CEN.PK2-1C and YUSM1009a. In recombinant strains from which the GRE3 gene was deleted, xylitol formation decreased twofold. Deletion of the GRE3 gene combined with expression of the xylA gene fromT. thermophilus on a replicative plasmid generated recombinant xylose utilizing S.cerevisiae strain TMB3102, which produced ethanol from xylose with a yield of 0.28 mmol of C from ...
Biotechnology for Biofuels. RESEARCH Open Access. Systematic and evolutionary engineering of a xylose isomerase-based pathway in Saccharomyces cerevisiae for efficient conversion yields. Sun-Mi Lee1,2, Taylor Jellison1 and Hal S Alper1,3*. Abstract. Background: Efficient xylose fermentation by yeast would improve the economical and sustainable nature of biofuels production from lignocellulosic biomass. However, the efficiency of xylose fermentation by the yeast Saccharomyces cerevisiae is suboptimal, especially in conversion yield, despite decades of research. Here, we present an improved performance of S. cerevisiae in xylose fermentation through systematic and evolutionary engineering approaches. Results: The engineering of S. cerevisiae harboring xylose isomerase-based pathway significantly improved the xylose fermentation performance without the need for intensive downstream pathway engineering. This strain contained two integrated copies of a mutant xylose isomerase, gre3 and pho13 deletion ...
TY - CHAP. T1 - Metabolic engineering of yeasts for production of bulk fermentation products from xylose. T2 - International Specialised Symposium on Yeasts, ISSY 25 AU - Miller, C.. AU - Rajgarhia, V.. AU - Ilmen, Marja. AU - Koivuranta, Kari. AU - Ruohonen, Laura. AU - Aristidou, Aristos. AU - Penttilä, Merja. AU - Suominen, Pirkko. PY - 2006. Y1 - 2006. N2 - Kluyveromyces marxianus, a yeast naturally assimilating but not fermenting xylose, was genetically engineered to produce ethanol from xylose efficiently. Genetic engineering included replacing the natural xylose utilization pathway via xylose reductase and xylitol dehydrogenase to xylulose by a fungal xylose isomerase converting xylose directly to xylulose. Furthermore xylulokinase was overexpressed to improve efficiency of xylose to ethanol fermentation. The resulting strain produced 37 g/L ethanol with a yield of 0.4 g/g xylose used and an ethanol production rate of 0.94 g/L*h in shake flask fermentation tests. The original strain ...
The recombinant Saccharomyces cerevisiae strains that acquired the ability to utilize xylose through metabolic and evolutionary engineering exhibit good performance when xylose is the sole carbon source in the medium (designated the X stage in the present work). However, the xylose consumption rate of strains is generally low after glucose depletion during glucose-xylose co-fermentation, despite the presence of xylose in the medium (designated the GX stage in the present work). Glucose fermentation appears to reduce the capacity of these strains to
Xylose fermentation in yeast has been a target of research for years, yet not all the factors that may affect xylose fermentation perfomance of yeast strains are known. In this study, the mutant S. cerevisiae strain TMB 3400, which has good xylose fermentation properties, was compared with its parental strain to examine the factors behind the improved xylose utilization at protein level. The proteome of the parental and the mutant strains were characterized by difference in gel electrophoresis (DiGE) to quantitatively identify proteins that are expressed at altered levels in the mutant. The most significant changes detected by proteome analysis were the 6-10-fold increased levels of xylose reductase, xylitol dehydrogenase and transketolase (Tkl1) in the mutant, which is in accordance with previous knowledge about xylose metabolism in yeast. The level of acetaldehyde dehydrogenase (Ald6) was also significantly increased. In addition, several proteins homologous to proteins from yeast species ...
TY - JOUR. T1 - Stepwise metabolic adaption from pure metabolization to balanced anaerobic growth on xylose explored for recombinant Saccharomyces cerevisiae. AU - Klimacek, Mario. AU - Kirl, Elisabeth. AU - Krahulec, Stefan. AU - Longus, Karin. AU - Novy, Vera. AU - Nidetzky, Bernd. PY - 2014. Y1 - 2014. UR - http://www.microbialcellfactories.com/content/13/1/37/abstract. U2 - 10.1186/1475-2859-13-37. DO - 10.1186/1475-2859-13-37. M3 - Article. VL - 13. SP - 1. EP - 12. JO - Microbial cell factories JF - Microbial cell factories SN - 1475-2859. IS - 37. ER - ...
A substantial portion of placental function is committed to the regulation of nutrient transfer from the dam to the fetus, with glucose being the major substrate for conceptus metabolism. Due to its homomorphism with glucose, xylose can be used as tracer for the assessment of placental nutrient transfer capacity. This study was designed to evaluate transplacental permeability to xylose in bovine pregnancies on Days 90 and 180 of gestation. In Experiment 1, pregnant and nonpregnant females were infused into the jugular vein or into the allantoic sac with a 10% xylose solution to evaluate the maternal plasma xylose disappearance and the existence of feto-maternal xylose transfer, respectively. Glucose and xylose concentrations were determined in venous blood samples collected at 0, 15, 30, 60, 90, 120, 150, and 180 min. A materno-fetal but not a feto-maternal xylose transport was observed in both gestational periods. In Experiment 2, pregnant animals were slaughtered on Days 90 or 180 of ...
Industrial biotechnology aims to develop robust microbial cell factories, such as Saccharomyces cerevisiae, to produce an array of added value chemicals presently dominated by petrochemical processes. Xylose is the second most abundant monosaccharide after glucose and the most prevalent pentose sugar found in lignocelluloses. Significant research efforts have focused on the metabolic engineering of S similar to cerevisiae for fast and efficient xylose utilization. This study aims to metabolically engineer S similar to cerevisiae, such that it can consume xylose as the exclusive substrate while maximizing carbon flux to biomass production. Such a platform may then be enhanced with complementary metabolic engineering strategies that couple biomass production with high value-added chemical. Saccharomyces cerevisiae, expressing xylose reductase, xylitol dehydrogenase and xylulose kinase, from the native xylose-metabolizing yeast Pichia stipitis, was constructed, followed by a directed evolution strategy to
TY - JOUR. T1 - Production of biofuels and chemicals from xylose using native and engineered yeast strains. AU - Kwak, Suryang. AU - Jo, Jung Hyun. AU - Yun, Eun Ju. AU - Jin, Yong-Su. AU - Seo, Jin Ho. PY - 2019/3/1. Y1 - 2019/3/1. N2 - Numerous metabolic engineering strategies have allowed yeasts to efficiently assimilate xylose, the second most abundant sugar component of lignocellulosic biomass. During the investigation of xylose utilization by yeasts, a global rewiring of metabolic networks upon xylose cultivation has been captured, as opposed to a pattern of glucose repression. A clear understanding of the xylose-induced metabolic reprogramming in yeast would shed light on the optimization of yeast-based bioprocesses to produce biofuels and chemicals using xylose. In this review, we delved into the characteristics of yeast xylose metabolism, and potential benefits of using xylose as a carbon source to produce various biochemicals with examples. Transcriptomic and metabolomic patterns of ...
The development of inhibitor tolerant ethanologenic yeasts is one of the important challenges for a successful bioethanol production process from lignocellulose. Furthermore, an efficient microorganism for bioethanol production has to be able to ferment xylose together with glucose since xylose represents a large fraction in the lignocellulosic biomass. Weak acids and phenolic compounds are some of the prevalent inhibitors generated during pretreatment of lignocellulose and they will be present in the fermentation broth stressing the yeast affecting the fermentation performance. Although some studies on the effect of organic acids on fermenting microorganisms have been published, there is a lack of knowledge on the effect of phenolic compounds on yeast and more concretely about the effect on the xylose fermentation performance. In this study, the effect of acetic acid and vanillin on yeast growth on glucose and xylose will be elucidated using synthetic media mimicking lignocellulosic hydrolysates. It is
Two xylose-utilizing yeast strains isolated from rotten wood collected in the rainforest in different mountains of Hainan province, southern China, were studied. Sequence analysis of the large subunit rDNA D1/D2 domain and internal transcribed spacer region revealed that the strains represent a novel anamorphic yeast species, for which the name Candida cellulosicola sp. nov. is proposed; the type strain is HNX16-2T ( = CGMCC 2.3503T = CBS 11952T). Phylogenetically, the novel species was closely related to a xylose-utilizing teleomorphic ascomycetous yeast species Spencermartinsiella europaea in the family Trichomonascaceae, but differed from the latter by 3.0 % mismatches in the D1/D2 domain.
During cultivation on a mixture of xylose and glucose, Bacteroides xylanolyticus X5-1 showed neither diauxic growth nor a substrate preference. Xylose-limited continuous-culture cells were able to consume xylose and glucose both as single substrates and as mixed substrates without any lag phase. When glucose was the growth-limiting substrate, the microorganism was unable to consume xylose. However, in the presence of a small amount of glucose or pyruvate, xylose was utilized after a short lag phase. In glucose-limited cells, xylose isomerase was present at low activity but xylulose kinase activity could not be detected. On addition of a mixture of xylose and glucose, xylose isomerase was induced immediately and xylulose kinase was induced after about 30 min. The induction of the two enzymes was sensitive to chloramphenicol, showing de novo synthesis. Xylose uptake in glucose-grown cells was very low, but the uptake rate could be increased when incubated with a xylose-glucose mixture. The ...
Accepted name: D-xylose reductase. Reaction: xylitol + NAD(P)+ = D-xylose + NAD(P)H + H+ Other name(s): XylR; XyrA; msXR; dsXR; monospecific xylose reductase; dual specific xylose reductase; NAD(P)H-dependent xylose reductase; xylose reductase. Systematic name: xylitol:NAD(P)+ oxidoreductase. Comments: Xylose reductase catalyses the initial reaction in the xylose utilization pathway, the NAD(P)H dependent reduction of xylose to xylitol. Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: References:. 1. Neuhauser, W., Haltrich, D., Kulbe, K.D. and Nidetzky, B. NAD(P)H-dependent aldose reductase from the xylose-assimilating yeast Candida tenuis. Isolation, characterization and biochemical properties of the enzyme. Biochem. J. 326 (1997) 683-692. [PMID: 9307017]. 2. Nidetzky, B., Bruggler, K., Kratzer, R. and Mayr, P. Multiple forms of xylose reductase in Candida intermedia: comparison of their functional properties using quantitative structure-activity ...
Bioconversion of xylose-the second most abundant sugar in nature-into high-value fuels and chemicals by engineered Saccharomyces cerevisiae has been a long-term goal of the metabolic engineering community. Although most efforts have heavily focused on the production of ethanol by engineered S. cerevisiae, yields and productivities of ethanol produced from xylose have remained inferior as compared with ethanol produced from glucose. However, this entrenched focus on ethanol has concealed the fact that many aspects of xylose metabolism favor the production of nonethanol products. Through reduced overall metabolic flux, a more respiratory nature of consumption, and evading glucose signaling pathways, the bioconversion of xylose can be more amenable to redirecting flux away from ethanol towards the desired target product. In this report, we show that coupling xylose consumption via the oxidoreductive pathway with a mitochondrially-targeted isobutanol biosynthesis pathway leads to enhanced product ...
The permeability characteristics of D- and L-xylose and D- and L-arabinose have been compared in isolated intact rat diaphragm muscle preparations, in the absence and presence of exogenous insulin. In the absence of added insulin, these pentoses distribute in less than a third of the total cell water. In the presence of added insulin, intracellular distribution of all these pentoses is increased. L-Xylose and D-arabinose distribute in 50 per cent of the intracellular water, whereas D-xylose and L-arabinose distribute in 80 per cent of the cell water. A significant lag period was observed before the insulin effect upon the penetration of L-xylose and D-arabinose was evident whereas the effect upon D-xylose and L-arabinose was rapid. The lag period with L-xylose could be abolished by pretreating the tissues with insulin for 1 hour, but such pretreatment had little effect on D-xylose. These results indicate that insulin has a biphasic effect upon the monosaccharide exclusion system in diaphragm ...
article{3edb5e2c-caaf-4646-9ecb-432a6bbf667b, abstract = {ABSTRACT: BACKGROUND: Simultaneous saccharification and fermentation (SSF) is a promising process option for ethanol production from lignocellulosic materials. However, both the overall ethanol yield and the final ethanol concentration in the fermentation broth must be high. Hence, almost complete conversion of both hexoses and pentoses must be achieved in SSF at a high solid content. A principal difficulty is to obtain an efficient pentose uptake in the presence of high glucose and inhibitor concentrations. Initial glucose present in pretreated spruce decreases the xylose utilization by yeast, due to competitive inhibition of sugar transport. In the current work, prefermentation was studied as a possible means to overcome the problem of competitive inhibition. The free hexoses, initially present in the slurry, were in these experiments fermented before adding the enzymes, thereby lowering the glucose concentration. RESULTS: This work ...
D-Xylose is a five-carbon aldose (pentose, monosaccharide) that can be catabolized or metabolized into useful products by a variety of organisms. There are at least four different pathways for the catabolism of D-xylose: An oxido-reductase pathway is present in eukaryotic microorganisms. Prokaryotes typically use an isomerase pathway, and two oxidative pathways, called Weimberg and Dahms pathways respectively, are also present in prokaryotic microorganisms. This pathway is also called the Xylose Reductase-Xylitol Dehydrogenase or XR-XDH pathway. Xylose reductase (XR) and xylitol dehydrogenase (XDH) are the first two enzymes in this pathway. XR is reducing D-xylose to xylitol using NADH or NADPH. Xylitol is then oxidized to D-xylulose by XDH, using the cofactor NAD. In the last step D-xylulose is phosphorylated by an ATP utilising kinase, XK, to result in D-xylulose-5-phosphate which is an intermediate of the pentose phosphate pathway. Because of the varying cofactors needed in this pathway and ...
TY - JOUR. T1 - Catalytic reaction profile for NADH-dependent reduction of aromatic aldehydes by xylose reductase from Candida tenuis.. AU - Mayr, P.. AU - Nidetzky, Bernd. PY - 2002. Y1 - 2002. UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12003638. M3 - Article. VL - 366. SP - 889. EP - 899. JO - Biochemical Journal. JF - Biochemical Journal. SN - 0264-6021. IS - 3. ER - ...
Scheffersomyces stipitis ATCC ® 58785™ Designation: CBS 6054 [CCRC 21777, IFO 10063, NRRL Y-11545] Application: Bioethanol production
Scheffersomyces stipitis ATCC ® 58785D-2™ Designation: genomic DNA from CBS 6054 (ATCC 58785) Application: Bioethanol production
Background Many Firmicutes bacteria, including solvent-producing clostridia such as Clostridium acetobutylicum, are able to utilize xylose, an abundant carbon source in nature. Nevertheless, homology...
There is provided an engineered host cells comprising (a) one or more mutations in one or more endogenous genes encoding a protein associated with iron metabolism; and (b) at least one gene encoding a polypeptide having xylose isomerase activity, and methods of their use thereof.
양송이의 알칼리 추출물에서 면역계의 주요인자인보체계와 macrophage를 활성화시키는 다당들을 분리, 정제하고 구조적 특성을 비교하였다. AB-20-IVa-2는 항보체 활성과 macrophage 활성능을 동시에 나타내는 단백다당으로 주요 구성당은 glucose | galactose | mannose 순으로 함유되어 있고 주요 구성아미노산은 phenylalanine (34.72%)과 valine (27.84%)이었다. AB-20-Ia와 AB-20-IIa-2a는 macrophage 활성을 갖고 있는 순수다당으로 AB-20-Ia의 주요 구성당은 glucose | xylose | mannose이고 AB-20-IIa-2a는 xylose | glucose | mannose이었다. AB-20-Ia, AB-20-IIa-2a, AB-20-IVa-2의 분자량은 각각 84만, 75만, 65만 정도로 추정되었다. AB-20-Ia, AB-20-IIa-2a, AB-20-IVa-2의 구조적 특성을 비교하기 위하여 NMR 분석, methyl화 분석을 통해 anomer 배위 양식과 당쇄 결합 양식을 조사하였다. AB-20-Ia는 ${\beta}-anomer$ 형태로 존재하는데 비해서 AB-20-IIa-2a는
Xylose or wood sugar is an aldopentose - a monosaccharide containing five carbon atoms and an aldehyde functional group. It has chemical formula C5H10O5 and is 40% as sweet as sucrose. Xylose is found in the embryos of most edible plants. The polysaccharide xylan, which is closely associated with cellulose, consists practically entirely of d-xylose. Corncobs, cottonseed hulls, pecan shells, and straw contain considerable amounts of this sugar. Xylose is also found in mucopolysaccharides of connective tissue and sometimes in the urine. Xylose is the first sugar added to serine or threonine residues during proteoglycan type O-glycosylation. Therefore xylose is involved in the biosythetic pathways of most anionic polysaccharides such as heparan sulphate and chondroitin sulphate. In medicine, xylose is used to test for malabsorption by administering a xylose solution to the patient after fasting. If xylose is detected in the blood and/or urine within the next few hours, it has been absorbed by the ...
Methods and systems for the isomerization and fermentation of xylose and hexose sugars using an immobilized enzyme system capable of sustaining two different pH microenvironments in a single vessel are disclosed. Bilayer particles are dispersed in a mixture comprising an ionic borate source and xylose. The bilayer particles have an inner of a xylose isomerase having a pH of 6 or above, and an outer region having a second enzymatic activity at an acidic pH ...
TY - JOUR. T1 - Structural explanation for the acquisition of glycosynthase activity. AU - Hidaka, Masafumi. AU - Fushinobu, Shinya. AU - Honda, Yuji. AU - Wakagi, Takayoshi. AU - Shoun, Hirofumi. AU - Kitaoka, Motomitsu. N1 - Funding Information: The Program for Promotion of Basic Research Activities for Innovative Biosciences (PROBRAIN) and Japan Society for the Promotion of Science for Young Scientists Research Fellowship 17-00182 (to M. H.).. PY - 2010/2. Y1 - 2010/2. N2 - Glycosynthases are engineered glycoside hydrolases (GHs) that catalyse the synthesis of glycoside from glycosyl-fluoride donors and suitable acceptors. We have determined five crystal structures of the glycosynthase mutants reducing-end xylose-releasing exo-oligoxylanase, an inverting GH, that exhibit various levels of glycosynthetic activities. At the active site of the Y198F mutant, the most efficient glycosynthase, a water molecule is observed at the same position as nucleophilic water (NW) in the parent enzyme, and the ...
The utilization of both C6 and C5 sugars is required for economical lignocellulosic bio-based processes. A co-culture system containing multiple strains of the same or different organisms holds promise for conversion of the sugar mixture available in different lignocellulosic feedstock into ethanol. Herein a co-culture kinetic model has been developed which can describe the co-cultivation of S. stipitis and S. cerevisiae for ethanol fermentation in mixed C6/C5 sugars. The predicted fermentation kinetics and ethanol production performance agreed well with experimental results, thus validating the model. The co-culture kinetic model has been implemented to design the optimal cell ratio for efficient conversion of rice straw or sugarcane bagasse feedstock into ethanol. The results reveal that the optimal co-culture system could enhance ethanol titer by up to 26 %, and ethanol productivity by up to 29 % compared to a single-strain culture. The maximum ethanol titer and productivity reached by the optimized
Xylose dehydrogenase plus Xylose mutarotase Enzyme for use in research, biochemical enzyme assays and in vitro diagnostic analysis. Purchase Xylogl...
Carbohydrates: me, Carbon-Dioxide: bi, Carbon-Isotopes, Cell-Membrane: me, Culture-Media, Enzyme-Repression, Escherichia-Coli: en, gd, me, Galactose, Glucose: me, Glycosides: me, Lactose: me, Mannose: me, Xylose: me. ...
Intracellular proteome of A. niger grown on xylose or maltose. Comparative analysis of the intracellular proteome of A. niger AB1.13 grown to late exponential/e
In an application of the presented high-density microarray, we identify a carbon source-based response conserved in three aspergilli. The design of the study involving three different species, grown on three different defined minimal media, at three different values of pH, increases the likelihood of the found genes to be the true conserved core response to growth on xylose and not responses relying on an extra factor in addition to xylose (with the possible exception of abundant oxygen). We also believe this approach validates our argument that the xylanolytic transcriptional activator XlnR is a conserved system, even though it has not previously been studied in A. nidulans. Backed by the finding that the 5′-GGNTAAA-3′ motif is present and in some cases conserved as syntenic regions in all three species, we propose that the motif is indeed a XlnR motif and conserved in A. nidulans, A. niger, and A. oryzae. As a point of interest, a study of the homologous genes and their promoter regions ...
A 33-year-old white homosexual man with AIDS and Kaposi sarcoma was seen because of diarrhea of 3 months duration and 11 kg weight loss. He claimed 10 to 40 bowel movements per day, which were often malodorous, awakened him from sleep, and were associated with cramping but not tenesmus. The volume, consistency, and frequency varied. Diarrheal volume roughly correlated with the volume of food consumed and was worsened by fatty foods and dairy products. Nonspecific antidiarrheal medications brought partial relief of symptoms. He had no fever, and a physical examination was unremarkable. Stool examinations for enteric bacteria and parasites were negative on three occasions. The patient was severely immunosuppressed, with a CD4 lymphocyte count of 5/mm3 (normal range, 532 to 1571 mm3). D-Xylose absorption was subnormal, with serum concentrations of 0.84 and 0.62 mmol/L 1 and 2 hours after the test dose (normal range, 1.3 to 3.3 mmol/L), and urinary xylose excretion of 0.056 (normal, ,0.20). Upper ...
A collaborative led by researchers at the University of Illinois and including the Lawrence Berkeley National Laboratory, the University of California at Berkeley, Seoul National University and BP have engineered a strain of Saccharomyces cerevisiae-the common industrial yeast-to co-ferment glucose and xylose simultaneously to produce ethanol. In a process of...
ID PISTI1_1_PE967 STANDARD; PRT; 362 AA. AC PISTI1_1_PE967; A3GHJ2; DT 00-JAN-0000 (Rel. 1, Created) DT 00-JAN-0000 (Rel. 2, Last sequence update) DT 00-JAN-0000 (Rel. 3, Last annotation update) DE Flags: Fragments; DE SubName: Full=Predicted protein;Flags: Fragment; (PISTI1_1.PE967). GN ORFNames=PICST_53517; OS SCHEFFERSOMYCES STIPITIS CBS 6054. OC Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; OC Saccharomycetales; Debaryomycetaceae; Scheffersomyces. OX NCBI_TaxID=322104; RN [0] RP -.; RG -.; RL -.; CC -!- SEQ. DATA ORIGIN: Translated from the HOGENOM CDS PISTI1_1.PE967. CC Pichia stipitis (strain CBS 6054 / NRRL Y-11545 / IFO 10063 / ATCC 5878 CC chromosome 1, complete sequence. CC -!- ANNOTATIONS ORIGIN:A3GHJ2_PICST CC -!- SIMILARITY: Contains 1 protein kinase domain. CC -!- GENE_FAMILY: HOG000233016 [ FAMILY / ALN / TREE ] DR UniProtKB/Swiss-Prot; A3GHJ2; -. DR EMBL; AAVQ01000002; EAZ63064.2; -; Genomic_DNA. DR RefSeq; XP_001387087.2; XM_001387050.1. DR ...
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Xylose Lysine Deoxycholate Agar is used for the isolation and differentiation of enteric pathogens. Conforms to Harmonized USP/EP/JP Requirements.
Xylose Lysine Deoxycholate Agar is used for the isolation and differentiation of enteric pathogens. Conforms to Harmonized USP/EP/JP Requirements.
TY - JOUR. T1 - Two different pathways for D-xylose metabolism and the effect of xylose concentration on the yield coefficient of L-lactate in mixed-acid fermentation by the lactic acid bacterium Lactococcus lactis IO-1. AU - Tanaka, K.. AU - Komiyama, A.. AU - Sonomoto, K.. AU - Ishizaki, A.. AU - Hall, S.. AU - Stanbury, P.. PY - 2002/10. Y1 - 2002/10. N2 - In lactic acid bacteria, pentoses are metabolized via the phosphoketolase pathway, which catalyzes the cleavage of D-xylulose-5-phosphate to equimolar amounts of glyceraldehyde 3-phosphate and acetylphosphate. Hence the yield coefficient of lactate from pentose does not exceed 1.0 mol/mol, while that of Lactococcus lactis IO-1(JCM7638) at high D-xylose concentrations often exceeds the theoretical value. This suggests that, in addition to the phosphoketolase pathway, L. lactis IO-1 may possess another metabolic pathway that produces only lactic acid from xylose. In the present study, the metabolism of xylose in L. lactis IO-1 was deduced ...
PubMed journal article: Probing the substrate binding site of Candida tenuis xylose reductase (AKR2B5) with site-directed mutagenesis. Download Prime PubMed App to iPhone, iPad, or Android
In this work, we rewired the xylose isomerase assimilation and mitochondrial isobutanol production pathways in the budding yeast Saccharomyces cerevisiae. We then increased the flux through these pathways by making gene deletions of BAT1, ALD6, and PHO13, to develop a strain (YZy197) that produces as much as 4 g/L of BCHAs (3.10 ± 0.18 g isobutanol/L and 0.91 ± 0.02 g 2-methyl-1-butanol/L) from xylose. This represents approximately a 28-fold improvement on the highest isobutanol titers obtained from xylose previously reported in yeast and the first report of 2-methyl-1-butanol produced from xylose. The yield of total BCHAs is 57.2 ± 5.2 mg/g xylose, corresponding to ~ 14% of the maximum theoretical yield. Respirometry experiments show that xylose increases mitochondrial activity by as much as 7.3-fold compared to glucose. ...
Exogenous anthrahydroquinone-2,6-disulfonate specifically increases xylose utilization during mixed sugar fermentation by Clostridium beijerinckii NCIMB ...
TY - JOUR. T1 - Metabolic characterization and transformation of the non-dairy Lactococcus lactis strain KF147, for production of ethanol from xylose. AU - Petersen, Kia Vest. AU - Liu, Jianming. AU - Chen, Jun. AU - Martinussen, Jan. AU - Jensen, Peter Ruhdal. AU - Solem, Christian. PY - 2017. Y1 - 2017. N2 - The non-dairy lactic acid bacterium Lactococcus lactis KF147 can utilize xylose as the sole energy source. To assess whether KF147 could serve as a platform organism for converting second generation sugars into useful chemicals, we characterized growth and product formation for KF147 when grown on xylose. In a defined medium KF147 was found to co-metabolize xylose and arginine, resulting in bi-phasic growth. Especially at low xylose concentrations, arginine significantly improved growth rate. To facilitate further studies of the xylose metabolism, we eliminated arginine catabolism by deleting the arcA gene encoding the arginine deiminase. The fermentation product profile suggested two ...
The xylose cluster of Lactobacillus pentosus consists of five genes, two of which, xylAB, form an operon and code for the enzymes involved in the catabolism of xylose, while a third encodes a regulatory protein, XylR. By introduction of a multicopy plasmid carrying the xyl operator and by disruption of the chromosomal xylR gene, it was shown that L. pentosus xylR encodes a repressor. Constitutive expression of xylAB in the xylR mutant is repressed by glucose, indicating that glucose repression does not require XylR. The xylR mutant displayed a prolonged lag phase compared to wild-type bacteria when bacteria were shifted from glucose to xylose medium. Differences in the growth rate in xylose medium at different stages of growth are not correlated with differences in levels of xylAB transcription in L. pentosus wild-type or xylR mutant bacteria but are positively correlated in Lactobacillus casei with a plasmid containing xylAB. Glucose repression was further investigated with a ccpA mutant. An ...
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Production of D-xylonate by the yeast S. cerevisiae provides an example of bioprocess development for sustainable production of value-added chemicals from cheap raw materials or side streams. Production of D-xylonate may lead to considerable intracellular accumulation of D-xylonate and to loss of viability during the production process. In order to understand the physiological responses associated with D-xylonate production, we performed transcriptome analyses during D-xylonate production by a robust recombinant strain of S. cerevisiae which produces up to 50 g/L D-xylonate. Comparison of the transcriptomes of the D-xylonate producing and the control strain showed considerably higher expression of the genes controlled by the cell wall integrity (CWI) pathway and of some genes previously identified as up-regulated in response to other organic acids in the D-xylonate producing strain. Increased phosphorylation of Slt2 kinase in the D-xylonate producing strain also indicated that D-xylonate production
TY - JOUR. T1 - Genomic features of Lactococcus lactis IO-1, a lactic acid bacterium that utilizes xylose and produces high levels of L-lactic acid. AU - Shimizu-Kadota, Mariko. AU - Kato, Hiroaki. AU - Shiwa, Yuh. AU - Oshima, Kenshiro. AU - Machii, Miki. AU - Araya-Kojima, Tomoko. AU - Zendo, Takeshi. AU - Hattori, Masahira. AU - Sonomoto, Kenji. AU - Yoshikawa, Hirofumi. PY - 2013. Y1 - 2013. N2 - Lactococcus lactis IO-1 (JCM7638) produces L-lactic acid predominantly when grown at high xylose concentrations, and its utilization is highly desired in the green plastics industry. Therefore it is worthwhile studying its genomic traits. In this study, we focused on (i) genes of possible horizontal transfer derivation (prophages, the nisin-sucrose transposon, and several restrictionmodification systems), and (ii) genes for the synthetic pathways of amino acids and vitamins in the IO-1 genome. In view of the results of this analysis, we consider their meanings in strain IO-1.. AB - Lactococcus ...
Seven closely related xylanolytic, thermophilic bacilli were isolated from mud and water samples from the Gonen and Diyadin hot springs, respectively located in the Turkish provinces of Balikesir and Agri. On the basis of morphology and biochemical characteristics, one of the isolates, designated strain G2T, was studied further. Strain G2T is a xylanolytic, sporulating, Gram-positive, rod-shaped bacterium. The isolate is a thermophilic (optimum temperature for growth, 55-60 °C), facultative anaerobe that grows on a wide range of carbon sources, including glucose, starch, xylose and mannitol. It expressed a high level of xylose isomerase activity on xylose and also on glucose. 16S rRNA gene sequence analysis showed that this isolate resembled Anoxybacillus flavithermus DSM 2641T (>97 % similarity), but 16S-23S rDNA internally transcribed spacer polymorphism PCR showed variation between DSM 2641T and isolate G2T. However, it is also known that analysis of 16S rRNA gene sequences may be insufficient to
Catalyzes the initial reaction in the xylose utilization pathway by reducing D-xylose into xylitol. Xylose is a major component of hemicelluloses such as xylan. Most fungi utilize D-xylose via three enzymatic reactions, xylose reductase (XR), xylitol dehydrogenase (XDH), and xylulokinase, to form xylulose 5-phosphate, which enters pentose phosphate pathway (By similarity).
In enzymology, a xylose isomerase (EC 5.3.1.5) is an enzyme that catalyzes the interconversion of D-xylose and D-xylulose. This enzyme belongs to the family of isomerases, specifically those intramolecular oxidoreductases interconverting aldoses and ketoses. The isomerase has now been observed in nearly a hundred species of bacteria. Xylose-isomerases are also commonly called fructose-isomerases due to their ability to interconvert glucose and fructose. The systematic name of this enzyme class is D-xylose aldose-ketose-isomerase. Other names in common use include D-xylose isomerase, D-xylose ketoisomerase, and D-xylose ketol-isomerase. The activity of D-xylose isomerase was first observed by Mitsuhashi and Lampen in 1953 in the bacterium Lactobacillus pentosus. Artificial production through transformed E.coli have also been successful. In 1957, the D-xylose isomerase activity on D-glucose conversion to D-fructose was noted by Kooi and Marshall. It is now known that isomerases have broad ...
Bioprospecting is an effective way to find novel enzymes from strains with desirable phenotypes. Such bioprospecting has enabled organisms such as Saccharomyces cerevisiae to utilize nonnative pentose sugars. Yet, the efficiency of this pentose catabolism (especially for the case of arabinose) remains suboptimal. Thus, further pathway optimization or identification of novel, optimal pathways is needed. Previously, we identified a novel set of xylan catabolic pathway enzymes from a superior pentose-utilizing strain of Ustilago bevomyces. These enzymes were used to successfully engineer a xylan-utilizing S. cerevisiae through a blended approach of bioprospecting and evolutionary engineering. Here, we expanded this approach to xylose and arabinose catabolic pathway engineering and demonstrated that bioprospected xylose and arabinose catabolic pathways from U. bevomyces offer alternative choices for enabling efficient pentose catabolism in S. cerevisiae. By introducing a novel set of xylose ...
D-Xylose or L-arabinose-consuming S. cerevisiae strains have previously been independently developed by introduction of heterologous enzymes necessary for the assimilation of either of the sugars [6, 7, 10-12]. However, co-fermentation of the two pentose sugars by S. cerevisiae has not, to the best of our knowledge, previously been reported. We have introduced both the arabinose and the xylose pathways in S. cerevisiae strains to investigate the effects and possible limitations of the combined metabolism of the two pentoses. Xylose utilization was enabled by overexpression of the P. stipitis genes coding for XR and XDH as well as the endogenous XK through chromosomal integration. Arabinose assimilation was enabled through heterologous expression of the bacterial arabinose pathway consisting of L-arabinose isomerase (AraA), L-ribulokinase (AraB) and L-ribulose-5-P-4-epimerase (AraD) genes.. The combination of xylose and arabinose pathways was first tested in a laboratory strain. However, ...
Purchase Recombinant Saccharomyces cerevisiae Protein RTA1(RTA1). It is produced in in vitro E.coli expression system. High purity. Good price.
Background Two major hurdles for successful production of second-generation bioethanol are the presence of inhibitory compounds in lignocellulosic media, and the fact that Saccharomyces cerevisiae cannot naturally utilise pentoses. There are recombinant yeast strains that address both of these issues, but co-utilisation of glucose and xylose is still an issue that needs to be resolved. A non-recombinant way to increase yeast tolerance to hydrolysates is by encapsulation of the yeast. This can be explained by concentration gradients occuring in the cell pellet inside the capsule. In the current study, we hypothesised that encapsulation might also lead to improved simultaneous utilisation of hexoses and pentoses because of such sugar concentration gradients. Results In silico simulations of encapsulated yeast showed that the presence of concentration gradients of inhibitors can explain the improved inhibitor tolerance of encapsulated yeast. Simulations also showed pronounced concentration ...
Understanding how new biochemical pathways evolve in a sexually reproducing population is a complex and largely unanswered question. We have successfully evolved a novel biochemical pathway in yeast using a sex based population approach.. For over 30 years, wild type Saccharomyces has been widely reported to not grow on xylose at all, but we discovered that most strains can grow, albeit at almost undetectable rates. A mass mated starting population of Saccharomyces cerevisiae strains was evolved under selection on Xylose Minimal Media (XMM) with forced sexual mating every ~two months for 1463 days. This produced a population that could grow on xylose as a sole carbon source. Initial studies show the xylose growth trait is quantitative and presumably governed by many genes. To investigate the evolution of the xylose phenotype, a xylose utilising strain MBG11a was isolated. MBG11a was sequenced with PacBio RSII long read sequencing at the Ramaciotti Centre for Genomics. A high quality complete ...
TY - GEN. T1 - Enhanced xylitol production through simultaneous co-consumption of cellobiose and xylose by an engineereed saccharomyces cerevisiae strain. AU - Oh, Eun Joong. AU - Ha, Suk Jin. AU - Kim, Soo Rin. AU - Galazka, Jonathan M.. AU - Cate, Jamie H.D.. AU - Su Jin, Yong. PY - 2011/1/1. Y1 - 2011/1/1. UR - http://www.scopus.com/inward/record.url?scp=85054765849&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=85054765849&partnerID=8YFLogxK. M3 - Conference contribution. AN - SCOPUS:85054765849. SN - 9781618397362. T3 - Fuels and Petrochemicals Division - Core Programming Topic at the 2011 AIChE Annual Meeting. BT - Fuels and Petrochemicals Division - Core Programming Topic at the 2011 AIChE Annual Meeting. PB - AIChE. ER - ...
Introduction. Lignocellulosic material containing cellulose, hemicellulose, and lignin is an abundant renewable organic resource that can be used for the production of energy and biochemicals (Weber et al., 2010). The conversion of both the cellulose and hemicellulose fractions for producing biochemicals is being intensively studied. Between 23% to 40% of the lignocellulosic biomass consists of hemicellulose, the main component being xylose in most hardwoods and annual plants (Lee et al., 1979). Whereas the fermentation of glucose can be carried out efficiently with the common brewers yeast (Saccharomyces cerevisiae), the bioconversion of the pentose fraction (xylose and arabinose) presents a challenge since it is not metabolized by this species. Over the past decades, numerous studies have been carried out on various aspects of D-xylose bioconversion (Winkelhausen and Kuzmanova, 1998; Townsend and Howarth, 2010). D-xylose can be used by bacteria, yeasts and fungi through different pathways ...
Response surface methodology and central composite design were used to optimize a biosynthesis medium for the production of xylanases by Streptomyces sp. P12-137 in submerged fermentation culture at pH 5.0, with wheat bran as substrate. The three variables involved in this research were the wheat bran, potassium nitrate and xylose concentrations. Statistical analysis of the results showed that, in the range studied, xylose and potassium nitrate concentrations had a significant effect on xylanase production. The optimized biosynthesis medium contained (in %, w/v): wheat bran 1.0, KNO3 1.0, xylose 0.5. This medium resulted in a 3-fold increased level of the xylanase (27.77 UA/ml) production compared to the initial level (8.30 UA/ml) after 120 h of fermentation, whereas the value predicted by the quadratic model was 26.45 UA/ml.
Hemicellulose consists primarily of pentose sugars, joined together in a polysaccharide chain with D-xylose as the most abundant component. Ileal digestibility and urinary excretion of D-xylose and associated effects of this pentose sugar on ileal and faecal digestibility of dry matter (DM), organic matter (OM), gross energy (GE) and nitrogen were studied in pigs. Castrated pigs were prepared with a post-valvular T-caecum cannula to measure ileal digestibility. Faecal digestibility was measured in non-cannulated pigs. D-xylose was given at dietary inclusion levels of 100 and 200 g/kg, and the control sugar, D-glucose, at a rate of 200 g/kg diet. Ileal digestibility of D-xylose as well as that of D-glucose was found to be close to 100%. The presence of D-xylose in the diet decreased ileal digesta pH and increased ileal flow of volatile fatty acids, suggesting the occurrence of microbial degradation of D-xylose in the pig small intestine. In pigs fed on the 100 g D-xylose/kg diet, 44.5% of the ...
At the most basic level, xylan is composed of differing numbers of xylose sugars, with zero, one or two arabinose side-chains. The xylans in cereal grains tend to contain high numbers of arabinose side-chains (making them highly substituted) with significant differences occurring between cereal varieties, across growing seasons and from one location to another.. The more highly substituted a xylan is, the more water-soluble it tends to become, and the greater the negative impact on digesta viscosity (caused by high levels of soluble long-chain xylans). The level of substitution also influences where any cleaving of the xylose backbone by a xylanase enzyme can take place.. It is a good example of how key xylanase characteristics dictate both how and where the enzyme can act, as well as the end-products subsequently produced. For example, endo-acting xylanases cleave the xylose backbone mid-chain, whilst exo-acting xylanases release free xylose or arabinose sugars from the ends. Even within ...
Lactococcus lactis subsp. lactis (Lactobacillus xylosus) strain NRRL B-4449xylose regulatory protein (xylR), xylose isomerase (xylA), xylulokinase(xylB), mutarotase (xylM), and xyloside transporter (xynT) genes, completecds; and beta-1,4-xylosidase (xynB) gene, partial ...
View Notes - Nucleic Acids from BIOL 357 at University of Louisville. Nucleic Acids- DNA & RNA Chapter 08 DNA- Deoxyribonucleic Acid Double stranded chains of pentose sugars (deoxyribose), separated
p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.,/p> ,p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.,/p> ,p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).,/p> ,p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x,sup>64,/sup> + x,sup>4,/sup> + x,sup>3,/sup> + x + 1. The algorithm is described in the ISO 3309 standard. ,/p> ,p class=publication>Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.,br /> ,strong>Cyclic redundancy and other checksums,/strong>,br /> ,a href=http://www.nrbook.com/b/bookcpdf.php>Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993),/a>),/p> Checksum:i ...
As a member of the wwPDB, the RCSB PDB curates and annotates PDB data according to agreed upon standards. The RCSB PDB also provides a variety of tools and resources. Users can perform simple and advanced searches based on annotations relating to sequence, structure and function. These molecules are visualized, downloaded, and analyzed by users who range from students to specialized scientists.
The cell volume fraction ofSaccharomyces cerevisiae accessible tod-xylose and other nonmetabolized sugars was found to correspond to 100% of cell water in resting yeast over a range of osmolarities of the medium. This sugar space was decreásed to 60% by nitrogen deficiency and to 82% by phosphorus deficiency. The space of N-deficient cells was significantly raised by pre-incubation with ammonium chloride, amino-acids and nucleotides from the yeast extract and by adenosine triphosphate while that of P-deficient cells was not significantly altered by analogous treatment. The xylose space was found to be markedly lower in growing than in resting cells. Urea (0.3-6%) had a depressing effect on the sugar space size while a variety of metabolic inhibitors were without influence. TheKm andV values ofd-xylose uptake bySaccharomyces cerevisiae R XII at 30° were found to be 180-192 mM and 680-730 mg. xylose/ml. cell volume/hr., respectively. These values were not affected by N-deficiency and by enrichment with
α-L-Arabinofuranosidases play an important role in the degradation of hemicellulosic and pectinaceous plant polysaccharides. Reflecting their importance, arabinofuranosidases are found in several distinct phylogenetic lineages, including glycoside hydrolase (GH) families 43, 51, 54, and 62. Though many α-L-arabinofuranosidase structures have been solved, there remained a significant gap in our understanding of GH51 enzymes; no structure of an industrially relevant fungal GH51 enzyme was known. A lack of sequence similarity between fungal and bacterial enzymes precluded any inference of key function-determining structural features. Of particular interest is the fact that, during the degradation of arabinoxylan, some fungal GH51 enzymes show weak activity towards doubly substituted xylose residues, while others do not. Missing activity towards doubly substituted positions necessitates the inclusion of another enzyme to fully degrade this substrate. Structural understanding of a fungal GH51 ...
strains display variability in their capsular polysaccharide cell morphology karyotype and virulence but the BAPTA relationship between these variables is poorly understood. BAPTA xylose residue content linked at the 4 to 0 position. The relative virulence of the colony types was WR > PH > SM as measured by CFU in rat lungs after intratracheal […]. ...
Effective dispersion of the active species over the support almost always guarantees high catalytic efficiency. To achieve this high dispersion, a favourable interaction of the active species with the support is crucial. We show here that the crystal structure of the titania support determines the interactio 2016 most accessed Catalysis Science and Technology articles
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Background Beta-1,4-glucuronyltransferase involved in O-mannosylation of alpha-dystroglycan (DAG1). Transfers a glucuronic acid (GlcA) residue onto a xylose (Xyl) acceptor to produce the glucuronyl-beta-1,4-xylose-beta...
A straightforward single-step process for the preparation or production of a novel family of carbohydrates has been developed. These new carbohydrates can find use as neutral detergents and surfactants. Carbohydrate moieties are linked to a carbohydrate chain via an amide bond. Carbohydrate moieties can be any monosaccharide and may include glucose, mannose, galactose, xylose, arabinose, ribose etc. The hydrophobic chain can be linear, branched, cyclic or aromatic.. ...
It catalyzes an exceptionally high rate of oxidation of a wide range of aldose sugars, including D-glucose, galactose, arabinose and xylose, and also the disaccharides lactose, cellobiose and maltose ...
The ONE-HOUR Western™ Detection System is designed to produce a high signal with a low background for quick and clear western analysis of proteins. GenScripts breakthrough ONE-HOUR Western™ technology simplifies the classical western blot analysis by skipping the secondary antibody binding and washing steps. The kits reduce the total western blot analysis time from 4.5 hours down to only one hour..
Pectin is also known to contain other neutral sugars which are present in side chains. The most common side chain sugars are xylose, galactose and arabinose. The sidechains tend to occur in groups and have led to the description of the pectin molecule as having hairy and smooth regions.. Commercially pectins are categorised according to their methoxy content and wether they from gels quickly or slowly. Roughly speaking pectins can be split in to high methoxy pectins (,50% esterified) and low methoxy pectins (,50%esterified). Low methoxy pectins can also be amidated or not. ...
DNA what is it. Pentose sugar (deoxyribose) Phosphate molecule Four nitrogenous bases Pyrimidines: cytosine and thymine Purines: adenine and guanine. Proteins. One or more polypeptides Composed of amino acids Slideshow 6743213 by imani-mcneil
Xylose. -. monosacharide, pentose Polydextrose. E 1200. synthetic polymer, ca. 1kcal/g Lactulose. -. synthetic disaccharide ...
The xylose in the nectar can be metabolised by the intestinal microbiotic flora of the small mouse Micaelamys namaquensis. ... The nectar is, however, fortified with a high sugar content; the sugars include xylose. The downward-pointing shape, the odd ...
I. Xylose lysine agars; new media for isolation of enteric pathogens". Am J Clin Pathol. 44 (4): 471-475. doi:10.1093/ajcp/44.4 ...
I. Xylose lysine agars; new media for isolation of enteric pathogens". Am J Clin Pathol. 44 (4): 471-475. PMID 5839918. v t e. ... Xylose Lysine Deoxycholate agar (XLD agar) is a selective growth medium used in the isolation of Salmonella and Shigella ... After exhausting the xylose supply Salmonella colonies will decarboxylate lysine, increasing the pH once again to alkaline and ... XLD agar contains: Agar plate MRS agar R2a agar Zajc-Satler J, Gragas AZ (1977). "Xylose lysine deoxycholate agar for the ...
Xylose is a sugar that does not require enzymes to be digested. The D-xylose test involves having a patient drink a certain ... quantity of D-xylose, and measuring levels in the urine and blood; if there is no evidence of D-xylose in the urine and blood, ... Craig RM, Atkinson AJ (July 1988). "D-xylose testing: a review". Gastroenterology. 95 (1): 223-31. doi:10.1016/0016-5085(88) ... Malabsorption can be detected by a test called the D-xylose absorption test. ...
Xylose when dehydrated becomes furfural. When xylose and fufural[check spelling] are the goal, acid catalysts, such as formic ... Xylose is in most cases the sugar monomer present in the largest amount, although in softwoods mannose can be the most abundant ... Xylans Xylans usually consist of backbone of β-(1→4)-linked xylose residues. And it could be further divided into homoxylans ... For instance, besides glucose, sugar monomers in hemicelluloses can include the five-carbon sugars xylose and arabinose, the ...
Uridine diphosphate D-xylose: acceptor xylosyltransferase of Cryptococcus laurentii. Interferon production in mice by cell wall ... Biosynthesis of uridine diphosphate-D-xylose. IV. Mechanism of action of UDP-glucuronate carboxyl-lyase. Schutzbach, J. S. and ... Biosynthesis of uridine diphosphate-D-xylose. V. UDP-D-glucuronate and UDP-D-galacturonate carboxy-lyase of Ampullariella ... Biosynthesis of uridine diphosphate-D-xylose. V. UDP-D-glucuronate and UDP-D-galacturonate carboxy-lyase of Ampullariella ...
UDP-D-xylose + CO2 Hence, this enzyme has one substrate, UDP-D-glucuronate, and two products, UDP-D-xylose and CO2. This enzyme ... The systematic name of this enzyme class is UDP-D-glucuronate carboxy-lyase (UDP-D-xylose-forming). Other names in common use ... Ankel H, Feingold DS (1965). "Biosynthesis of uridine diphosphate D-xylose. 1. Uridine diphosphate glucuronate carboxy-lyase of ...
As such xylose constitutes the second most abundant carbohydrate moiety in nature. Xylose can be produced from wood or ... coding for xylose reductase and xylitol dehydrogenase, respectively. The concerted action of these enzymes converts xylose to ... which contain a large amount of xylose. In response, S. cerevisiae has been engineered to ferment xylose through the addition ... Native strains of S. stipitis have been shown to produce ≈50 g/l ethanol in 48 h from pure xylose in defined minimal medium ...
Syntheses have been accomplished from D-ribose and D-xylose. Carter, H. E.; Sweeley, C. C.; Daniels, E. E.; McNary, J. E.; ... 1976). "Synthesis of streptolidine from D-xylose". Bulletin of the Chemical Society of Japan. 49 (12): 3611-3614. doi:10.1246/ ...
Proteoglycan (PG) synthesis is initiated by the transfer of D-xylose from UDP-xylose to a serine residue in core proteins. This ... Many Beta-D-xylosides have been studied for use as xylose primes with varying results. Priming requires the Beta-anomer of ... Beta-D-xylosides consist of a xylose in beta linkage to an aglycone. The aglycone often consists of a hydrophobic compound ... A xyloside is a type of glycoside derived from the sugar xylose. ... xylose. Priming activity correlates with the activity of the ...
Winkelhausen, Eleonora; Kuzmanova, Slobodanka (1998). "Microbial conversion of d-xylose to xylitol". Journal of Fermentation ...
... assimilate xylose by expression of xylose reductase and xylitol dehydrogenase. The strain was able to convert rice straw ... However, conversion of xylose, the pentose sugar of hemicellulose hydrolyzate, is a limiting factor, especially in the presence ... Karhumaa K, Wiedemann B, Hahn-Hagerdal B, Boles E, Gorwa-Grauslund MF (2006) Co-utilization of L-arabinose and D-xylose by ... For example, in the hydrolysate of corn stover, approximately 30% of the total fermentable sugars is xylose. As a result, the ...
They produce acid from arabinose, glucose and xylose. They do not produce indole or reduce nitrate. Symptoms of C. ...
In 2014 a low-temperature 50 °C (122 °F), atmospheric-pressure enzyme-driven process to convert xylose into hydrogen with ... doi:10.1016/0076-6879(66)09093-1. Slein MW (1955). "Xylose isomerase from Pasteurella pestis, strain A-1122". J. Am. Chem. Soc ... Stumpf PK, Horecker BL (February 1956). "The role of xylulose 5-phosphate in xylose metabolism of Lactobacillus pentosus". The ... "High-yield production of dihydrogen from xylose by using a synthetic enzyme cascade in a cell-free system". Angewandte Chemie. ...
It can uptake both glucose and xylose simultaneously. When grown in old oil with high levels of polymerized triglyceride, the ...
Song S, Park C (1998). "Utilization of D-ribose through D-xylose transporter". FEMS Microbiol. Lett. 163 (2): 255-61. doi: ...
However, xylose (backbone of xylan) is a pentose sugar that is hard to ferment during biofuel conversion because microorganisms ... The main constituent of xylan can be converted into xylitol (a xylose derivative) which is used as a natural food sweetener, ... Xylanase catalyzes the catabolism of xylan into xylose. Given that plants contain a lot of xylan, xylanase is thus important to ... Xylans are polysaccharides made up of β-1,4-linked xylose (a pentose sugar) residues with side branches of α-arabinofuranose ...
... s (XOS) are polymers of the sugar xylose. They are produced from the xylan fraction in plant fiber. Their C5 ...
A polysaccharide of xylose Champe, Harvey, Ferrier. Biochemistry 4th Edition. 2008. 90. v t e. ...
"The structure and function of yeast xylose (aldose) reductases". Yeast. 14 (11): 977-84. doi:10.1002/(sici)1097-0061(199808)14: ...
Xylose lysine deoxycholate is selective for Gram-negative bacteria. Buffered charcoal yeast extract agar is selective for ...
Saprophytic growth uses D-xylose, D-mannose, and cellobiose. The fungus uses nitrite, nitrate, and ammonium for its nitrogen ...
... is a moderately thermophilic, xylose-utilizing, endospore-forming bacterium. It is Gram-positive and rod ... nov., a moderately thermophilic, xylose-utilizing, endospore-forming bacterium". International Journal of Systematic and ...
Formation of Tetroses from D-Xylose and L-Arabinose". Acta Chem. Scand. 26: 1709-1710. doi:10.3891/acta.chem.scand.26-1709. ... oxidation of D-xylose and L-arabinose to D-threose and L-erythrose respectively, and oxidation of L-sorbose to afford L-threose ...
Xylose isomerase acts to convert fructose sugars into glucose. Dietary supplements of xylose isomerase may improve some ... There is no known cure, but an appropriate diet and the enzyme xylose isomerase can help. The ingestion of glucose ... Komericki, P.; Akkilic-Materna, M.; Strimitzer, T.; Weyermair, K.; Hammer, H.F.; Aberer, W. (2012). "Oral xylose isomerase ...
D-xylose 1-dehydrogenase (NADP+) Ja 1.1.1.181 cholest-5-ene-3beta,7alpha-diol 3beta-dehydrogenase Ja ...
One noticeable change was reduced levels of xylitol, a byproduct of xylose fermentation which can inhibit the strain's xylose ... An extensive adaptation process was used to improve xylose fermentation in Z. mobilis. By adapting a strain in a high ... Wild-type Z. mobilis cannot ferment C5 sugars like xylose and arabinose which are important components of lignocellulosic ... Agrawal, Manoj; Mao, Z; Chen, RR (2011). "Adaptation yields a highly efficient xylose-fermenting Zymomonas mobilis strain". ...
Yellow sugar Xylose List of syrups "Hidden in Plain Sight". SugarScience.UCSF.edu. 2013-11-17. Retrieved 2018-09-02. Coelho, ...
Other names in common use include D-xylose isomerase, D-xylose ketoisomerase, and D-xylose ketol-isomerase. The activity of D- ... and rarely grown on D-xylose. L. xylosus was recognized to be distinct for its ability to grow on D-xylose. Xylose isomerase in ... In enzymology, a xylose isomerase (EC 5.3.1.5) is an enzyme that catalyzes the interconversion of D-xylose and D-xylulose. This ... In the isomerization of xylose, crystal data has shown that xylose sugar binds to the enzyme in an open chain conformation. ...
A xylose test checks the levels of xylose in blood and urine. Low levels can be a sign of a malabsorption disorder. Learn more. ... also known as D-xylose, is a type of sugar thats normally easily absorbed by the body. ... Other names: xylose tolerance test, xylose absorption test, D-xylose tolerance test, D-xylose absorption test ... What is a xylose test?. Xylose, also known as D-xylose, is a type of sugar that is normally easily absorbed by the intestines. ...
Other names: D-Xylose; Xylose, d-; (+)-Xylose; Xylo-Pfan; D-(+)-Xylose; Wood sugar ...
If xylose is detected in blood and/or urine within the next few hours, it has been absorbed by the intestines. High xylose ... Xylose (cf. Greek: ξύλον, xylon, "wood") is a sugar first isolated from wood, and named for it. Xylose is classified as a ... Xylose contains 2.4 calories per gram (lower than glucose or sucrose, approx. 4 calories per gram). In animal medicine, xylose ... The dextrorotary form, d-xylose, is the one that usually occurs endogenously in living things. A levorotary form, l-xylose, can ...
D-xylose). The test helps detect if nutrients are being properly absorbed. ... D-xylose absorption is a laboratory test to check how well the intestines absorb a simple sugar ( ... D-xylose absorption is a laboratory test to check how well the intestines absorb a simple sugar (D-xylose). The test helps ... You will be asked to drink 8 ounces (240 ml) of water that contains 25 grams of a sugar called d-xylose. The amount of d-xylose ...
2007). "Comparison of the xylose reductase-xylitol dehydrogenase and the xylose isomerase pathways for xylose fermentation by ... Xylose reductase (XR) and xylitol dehydrogenase (XDH) are the first two enzymes in this pathway. XR reduces D-xylose to xylitol ... The Weimberg pathway is an oxidative pathway where the D-xylose is oxidized to D-xylono-lactone by a D-xylose dehydrogenase ... In this pathway the enzyme xylose isomerase converts D-xylose directly into D-xylulose. D-xylulose is then phosphorylated to D- ...
Xylose definition, a colorless, crystalline pentose sugar, C5H10O5, derived from xylan, straw, corncobs, etc., by treating with ... xylose. *. No trace of this substance is obtained from the xylose product. ... But glucose can be more cheaply obtained from other starchy or woody materials and they cannot find a market for the xylose. ... They have found it possible to work up the corn cobs into glucose and xylose by heating with acid. ...
Xylose Lysine Desoxycholate (XLD) Agar. Storage. May be stored up to 30 days under refrigeration (4 ± 2°C).. ...
L-xylose synonyms, L-xylose pronunciation, L-xylose translation, English dictionary definition of L-xylose. n. A crystalline ... xylose. (redirected from L-xylose). Also found in: Thesaurus, Medical, Encyclopedia. xy·lose. (zī′lōs′). n.. A crystalline ... L-xylose - definition of L-xylose by The Free Dictionary https://www.thefreedictionary.com/L-xylose ... D-xylose, L-xylose, Adonitol, B-methyl xyloside, galactose, glucose, fructose, mannose, L-sorbose, rhamnose, dulcitol, inositol ...
... IUPAC name Xylose Identifiers CAS number 58-86-6L: 609-06-3DL: 41247-05-6&c=0&v= D: 58-86-6L: 609-06-3DL: 41247- ... In animal medicine, xylose is used to test for malabsorption by administering to the patient in water after fasting. If xylose ... Arabinose , Deoxyribose , Lyxose , Ribose , Ribulose , Xylose , Xylulose Hexoses: Glucose , Galactose , Mannose , Gulose , ... Xylose or wood sugar is an aldopentose - a monosaccharide containing five carbon atoms and including an aldehyde functional ...
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Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice ...
Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting ... Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting ... arabinose and xylose. Different pathways can be introduced in S. cerevisiae to provide arabinose and xylose utilisation. In ... the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways, respectively, in genetically identical strains. The ...
Sinorhizobium meliloti 1021 plasmid pSymB UDP-xylose synthase 2 gene, complete c... Sinorhizobium meliloti 1021 plasmid pSymB ... Sinorhizobium meliloti 1021 plasmid pSymB UDP-xylose synthase 2 gene, complete cds. GenBank: GU062742.1 ...
The PDB archive contains information about experimentally-determined structures of proteins, nucleic acids, and complex assemblies. As a member of the wwPDB, the RCSB PDB curates and annotates PDB data according to agreed upon standards. The RCSB PDB also provides a variety of tools and resources. Users can perform simple and advanced searches based on annotations relating to sequence, structure and function. These molecules are visualized, downloaded, and analyzed by users who range from students to specialized scientists.
... *Formula: C20H51NO5Si5 ... D-(+)-Xylose, tetrakis(trimethylsilyl) ether, trimethylsilyloxime (isomer 1). *D-(-)-Ribose, tetrakis(trimethylsilyl) ether, ...
Carbohydrate metabolism, Xylose metabolismUniRule annotation. ,p>Information which has been generated by the UniProtKB ... Xylose isomeraseUniRule annotation. ,p>Information which has been generated by the UniProtKB automatic annotation system, ... Belongs to the xylose isomerase family.UniRule annotation. ,p>Information which has been generated by the UniProtKB automatic ... tr,A0A133LKN2,A0A133LKN2_BIFLN Xylose isomerase OS=Bifidobacterium longum OX=216816 GN=xylA PE=3 SV=1 ...
Xylose Tolerance 5-Hr, No Ur. 016626. Xylose - 1 hour. mg/dL. 23940-0. ... Xylose Tolerance 5-Hr, No Ur. 016634. Xylose - 2 hour. mg/dL. 23943-4. ... Xylose Tolerance 5-Hr, No Ur. 016246. Xylose - 3 hour. mg/dL. 10869-6. ... Xylose Tolerance 5-Hr, No Ur. 016329. Xylose - 4 hour. mg/dL. 13030-2. ...
Find more ways to say xylose, along with related words, antonyms and example phrases at Thesaurus.com, the worlds most trusted ... They have found it possible to work up the corn cobs into glucose and xylose by heating with acid.. CREATIVE CHEMISTRYEDWIN E. ... But glucose can be more cheaply obtained from other starchy or woody materials and they cannot find a market for the xylose.. ... The wound gums, for example, yield arabinose, and the wood gums yield xylose.. THE CHEMISTRY OF PLANT LIFEROSCOE WILFRED ...
Xylose Lysine Deoxycholate Agar is used for the isolation and differentiation of enteric pathogens. Conforms to Harmonized USP/ ... Xylose Lysine Deoxycholate (XLD) Agar - English - US Xylose Lysine Deoxycholate (XLD) Agar - Finnish - Finland Xylose Lysine ... Xylose Lysine Deoxycholate (XLD) Agar - Italian - Italy Xylose Lysine Deoxycholate (XLD) Agar - Japanese - Japan Xylose Lysine ... Xylose Lysine Deoxycholate (XLD) Agar - Spanish - South America Xylose Lysine Deoxycholate (XLD) Agar - Spanish - US Xylose ...
The recently published report titled United States D-Xylose Industry 2018 Market Research Report is an in depth study providing ... 1 D-Xylose Overview. 1.1 Product Overview and Scope of D-Xylose. 1.2 Classification of D-Xylose by Product Category. 1.2.1 ... 1.2.3 Refine Grade D-Xylose. 1.2.4 Raw Material Grade D-Xylose. 1.3 United States D-Xylose Market by Application/End Users. 1.3 ... 7 D-Xylose Manufacturing Cost Analysis. 7.1 D-Xylose Key Raw Materials Analysis. 7.1.1 Key Raw Materials. 7.1.2 Price Trend of ...
A kinetic analysis of D-xylose transport in Rhodotorula glutinis by Mary Ellen Alcorn; 1 edition; First published in 1977; ... Are you sure you want to remove A kinetic analysis of D-xylose transport in Rhodotorula glutinis from your list? ... A kinetic analysis of D-xylose transport in Rhodotorula glutinis 1 editions ... A kinetic analysis of D-xylose transport in Rhodotorula glutinis Mary Ellen Alcorn ...
Home , Patient Care , Specialties and Services , Pathology , XYLOSE ABSORPTION TEST ADULT URINE ... Give oral dose of 5g d(+) xylose in about 250 mL of water. 3. Withhold food intake but encourage fluid intake. 4. Collect urine ... XYLOSE ABSORPTION TEST (ADULT), URINE - Test discontinued w.e.f. 01 July 2019 Synonym(s): ...
... Hongxi Zhang,1,2 Xuefeng ... H. Zhang, X. Zhao, X. Ding et al., "A study on the consecutive preparation of d-xylose and pure superfine silica from rice husk ...
All of them, i.e., Hxt1, Hxt2, Hxt4, and Hxt7 were capable of xylose uptake. Their affinities for xylose varied, K (m) values ... The new transporter homologue, Trxlt1 thus appears to code for a protein specific for xylose uptake. In addition, xylose- ... Xylose transport studies with xylose-utilizing Saccharomyces cerevisiae strains expressing heterologous and homologous ... In the present study, we modified xylose uptake properties of a recombinant xylose-utilizing yeast Saccharomyces cerevisiae by ...
Although cells can be engineered with required enzymes, they fail to recognize xylose as a consumable sugar for unknown reasons ... We used comparative systems biology across strains with progressive improvements in xylose utilization to understand the ... However, many microbes, including yeast, cannot use the xylose comprising ~30% of hemicellulosic sugars, especially under ... metabolic and regulatory logic of anaerobic xylose fermentation. Mutations in evolved strains trigger signaling pathways that ...
We also Provide Trading Suppliers & Manufacture for 25990-60-7 DL-XYLOSE. ... Product Name: DL-XYLOSE. *Synonyms: XYLOSE, DL-;XYLOSE;DL-XYL;DL-XYLOSE;Xylose (9CI);(2S,3R,4S,5R)-oxane-2,3,4,5-tetrol;(2S,3R, ... Xylose is a sugar first isolated from wood. Xylose is classified as a monosaccharide of the aldopentose type, which means that ... DL-xylose. Cas No: 25990-60-7. USD $ 3.0-3.0 / Kilogram. 1 Kilogram. 1-100 Metric Ton/Month. Hangzhou Dayangchem Co., Ltd.. ...
Biology · Amino acid comparison · D-xylose isomerase · D-xylulose kinase · NMR analysis · Regulatory protein · Xylose · Xylose ... When L. brevis was cultivated in a mixture of D-glucose and D-xylose, the D-xylose isomerase and D-xylulose kinase activities ... A cluster of three genes involved in D-xylose catabolism (viz. xylose genes) in Lactobacillus pentosus has been cloned in ... NMR analysis confirmed that 13C-xylose was converted into 13C-acetate in L. casei cells transformed with L. pentosus xylose ...
D-xylose is normally easily absorbed by the intestines . When problems with absorption occur, D-xylose... ... The D-xylose absorption test measures the level of D-xylose, a type of sugar, in a blood or urine sample. This test is done to ... Blood levels of D-xylose are highest about 2 hours after drinking the D-xylose solution. Almost all of the D-xylose is ... The D-xylose absorption test measures the level of D-xylose, a type of sugar, in a blood or urine sample. This test is done to ...
Xylose isomeraseUniRule annotation. ,p>Manual validated information which has been generated by the UniProtKB automatic ... Belongs to the xylose isomerase family.UniRule annotation. ,p>Manual validated information which has been generated by the ... sp,B0BTI9,XYLA_ACTPJ Xylose isomerase OS=Actinobacillus pleuropneumoniae serotype 3 (strain JL03) OX=434271 GN=xylA PE=3 SV=1 ...
  • In enzymology, a xylose isomerase (EC 5.3.1.5) is an enzyme that catalyzes the interconversion of D-xylose and D-xylulose. (wikipedia.org)
  • The systematic name of this enzyme class is D-xylose aldose-ketose-isomerase. (wikipedia.org)
  • Other names in common use include D-xylose isomerase, D-xylose ketoisomerase, and D-xylose ketol-isomerase. (wikipedia.org)
  • The activity of D-xylose isomerase was first observed by Mitsuhashi and Lampen in 1953 in the bacterium Lactobacillus pentosus. (wikipedia.org)
  • In 1957, the D-xylose isomerase activity on D-glucose conversion to D-fructose was noted by Kooi and Marshall. (wikipedia.org)
  • Most pentoses and some hexoses are all substrates for D-xylose isomerase. (wikipedia.org)
  • Conversion of glucose to fructose by xylose isomerase was first patented in the 1960s, however, the process was not industrially viable as the enzymes were suspended in solution, and recycling the enzyme was problematic. (wikipedia.org)
  • An immobile xylose isomerase that was fixed on a solid surface was first developed in Japan by Takanashi. (wikipedia.org)
  • Hence D-xylose isomerase is used to produce these rare sugars which have very important applications in biology despite their low abundance. (wikipedia.org)
  • Xylose isomerase that can be isolated from red Chinese rice wine, which contains the bacterium Lactobacillus xylosus. (wikipedia.org)
  • Xylose isomerase in L. xylosus has a molecular weight of about 183000 Daltons. (wikipedia.org)
  • Thermal tests were also done by Kei Y. and Noritaka T. and the xylose isomerase was found to be thermally stable to about 60 degrees Celsius Xylose isomerase has a structure that is based on eight alpha/beta barrels that create an active site holding two divalent magnesium ions. (wikipedia.org)
  • Xylose isomerase enzymes exhibit a TIM barrel fold with the active site in the centre of the barrel and a tetrameric quaternary structure. (wikipedia.org)
  • In this pathway the enzyme xylose isomerase converts D-xylose directly into D-xylulose. (wikipedia.org)
  • At equilibrium, the isomerase reaction results in a mixture of 83% D-xylose and 17% D-xylulose because the conversion of xylose to xylulose is energetically unfavorable. (wikipedia.org)
  • Many attempts at expressing bacterial isomerases were not successful due to misfolding or other problems, but a xylose isomerase from the anaerobic fungus Piromyces Sp. (wikipedia.org)
  • One advantage claimed for S. cerevisiae engineered with the xylose isomerase is that the resulting cells can grow anaerobically on xylose after evolutionary adaptation. (wikipedia.org)
  • Overexpression of the four genes encoding non-oxidative pentose phosphate pathway enzymes Transaldolase, Transketolase, Ribulose-5-phosphate epimerase and Ribose-5-phosphate ketol-isomerase led to both higher D-xylulose and D-xylose fermentation rate. (wikipedia.org)
  • In this study, the bacterial arabinose isomerase pathway was combined with two different xylose utilisation pathways: the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways, respectively, in genetically identical strains. (mendeley.com)
  • Comparison with the aligned amino acid sequences of D-xylose isomerases of different bacteria suggests that L. pentosus D-xylose isomerase belongs to the same similarity group as B. subtilis and E. coli D-xylose isomerase and not to a second similarity group comprising D-xylose isomerases of Streptomyces violaceoniger, Ampullariella sp. (tudelft.nl)
  • The organization of the L. pentosus xylose genes, 5'-xylR (1167 bp, repressor) - xylA (1350 bp, D-xylose isomerase) - xylB (1506 bp, D-xylulose kinase) - 3' is similar to that in B. subtilis. (tudelft.nl)
  • A 3-kb region, located downstream of the Lactobacillus brevis xylA gene (encoding D-xylose isomerase), was cloned in Escherichia coli TG1. (tudelft.nl)
  • The existence of a functional XylR was further suggested by the presence of xylO sequences upstream of xylA and xylT and by the requirement of D-xylose for the induction of D-xylose isomerase, D- xylulose kinase, and D-xylose transport activities in L. brevis. (tudelft.nl)
  • When L. brevis was cultivated in a mixture of D-glucose and D-xylose, the D-xylose isomerase and D-xylulose kinase activities were reduced fourfold and the D- xylose transport activity was reduced by sixfold, suggesting catabolite repression by D-glucose of D-xylose assimilation. (tudelft.nl)
  • Brat D, Boles E, Wiedemann B (2009) Functional expression of a bacterial xylose isomerase in Saccharomyes cerevisiae . (springer.com)
  • 2007). In one of these, D-xylose can be directly converted to D-xylulose by xylose isomerase (Aristidou and Penttila 2000) without the participation of cofactors. (scielo.br)
  • To increase the substrate spectrum, we implemented three alternative xylose utilization pathways, namely the Isomerase, Weimberg, and Dahms pathways. (frontiersin.org)
  • and (b) at least one gene encoding a polypeptide having xylose isomerase activity, and methods of their use thereof. (energy.gov)
  • When the bacterial enzyme xylose isomerase (XI) from Thermus thermophilus was produced in S . cerevisiae, xylose utilization and ethanol formation were demonstrated. (asm.org)
  • To force simultaneous utilisation of xylose and glucose, the genes encoding glucose-6-phosphate isomerase (PGI1) and ribulose-5-phosphate epimerase (RPE1) were deleted in a xylose-isomerase-based xylose-fermenting strain with a modified oxidative pentose-phosphate pathway. (deepdyve.com)
  • When expressed in S. pastorianus, the Trichoderma reesei xylose oxidoreductase pathway was more efficient at alcohol production from xylose than the xylose isomerase pathway. (tcd.ie)
  • A novel xylose isomerase that is not homologous to previously characterized xylose isomerase, was identified in C. acetobutylicum and several other Clostridia species. (biomedcentral.com)
  • Subsequently a bacterial xylose isomerase (XI) gene was introduced into S. cerevisiae. (sun.ac.za)
  • Bacterial xylose isomerase converts D-xylose to xylulose in a single step, while eukaryotic pathways produce the intermediate xylitol. (sun.ac.za)
  • The chosen gene encodes for a putative xylose isomerase gene (xylA) from the bacterium Bacteroides thetaiotaomicron, which has not previously been transformed into yeast. (sun.ac.za)
  • A synthetic D-xylose isomerase gene (SXI) based on the B. thetaiotaomicron XI amino acid sequence, but optimised for S. cerevisiae codon bias, was designed and manufactured. (sun.ac.za)
  • While major differences were not observed in gene and gene-product expression for enzymes associated with metabolic pathways under the different substrate conditions, xylulokinase and xylose isomerase of the pentose phosphate pathway were found to be highly up-regulated on five carbon sugars compared to hexoses. (biomedcentral.com)
  • Principally, genes encoding xylose isomerase (XI) from bacteria and fungi [ 4 , 5 ], or genes encoding xylose reductase (XR) and xylitol dehydrogenase (XDH) from fungi [ 6 , 7 ] can be introduced. (biomedcentral.com)
  • Studies on flux through the oxidative pentose phosphate pathway during D-xylose metabolism have revealed that limiting the rate of this step may be beneficial to the efficiency of fermentation to ethanol. (wikipedia.org)
  • The strains were compared with respect to aerobic growth in arabinose and xylose batch culture and in anaerobic batch fermentation of a mixture of glucose, arabinose and xylose. (mendeley.com)
  • The role of the XylT protein was confirmed by the accumulation of D-xylose in L. plantarum 80 cells, and this accumulation was dependent on the proton motive force generated by either malolactic fermentation or by the metabolism of D- glucose. (tudelft.nl)
  • Thermophilic anaerobic ethanol producing bacteria can therefore be considered for fermentation of D-xylose. (osti.gov)
  • and producing xylitol with high yield based on repeated batch fermentation using a hydrolysate containing xylose and arabinose as a carbon source. (freepatentsonline.com)
  • Cloning novel sugar transporters from Scheffersomyces (Pichia) stipitis allowing D-xylose fermentation by recombinant Saccharomyces cerevisiae. (sigmaaldrich.com)
  • Since uptake of xylose limits its fermentation, we aimed to identify novel sugar transporters from Scheffersomyces stipitis that allow xylose uptake and fermentation by engineered Saccharomyces cerevisiae. (sigmaaldrich.com)
  • 1979). Whereas the fermentation of glucose can be carried out efficiently with the common brewer's yeast ( Saccharomyces cerevisiae ), the bioconversion of the pentose fraction (xylose and arabinose) presents a challenge since it is not metabolized by this species. (scielo.br)
  • Arbetet i denna avhandling har syftat till att utveckla en SSCF-process (simultaneous saccharification and co-fermentation) där jästen så effektivt som möjligt tar upp och fermenterar såväl xylos som glukos, som frigörs i processen då enzymer (cellulaser) bryter ner lignocellulosa till olika socker. (lu.se)
  • Intracellular hydrolysis of cellobiose minimizes glucose repression of xylose fermentation allowing co-consumption of cellobiose and xylose. (greencarcongress.com)
  • The resulting yeast strains, co-fermented cellobiose and xylose simultaneously and exhibited improved ethanol yield when compared to fermentation with either cellobiose or xylose as sole carbon sources. (greencarcongress.com)
  • The successful integration of cellobiose and xylose fermentation pathways in yeast is a critical step towards enabling economic biofuel production. (greencarcongress.com)
  • If you do the fermentation by using only cellobiose or xylose, it takes 48 hours. (greencarcongress.com)
  • But if you do the co-fermentation with the cellobiose and xylose, double the amount of sugar is consumed in the same amount of time and produces more than double the amount of ethanol. (greencarcongress.com)
  • Although some studies on the effect of organic acids on fermenting microorganisms have been published, there is a lack of knowledge on the effect of phenolic compounds on yeast and more concretely about the effect on the xylose fermentation performance. (chalmers.se)
  • Furthermore differences in gene expression of key genes involved in acetic acid and vanillin tolerance and xylose fermentation will be studied. (chalmers.se)
  • A total of six different cellobiose assimilating pathways were constructed and compared in a laboratory S. cerevisiae strain capable of xylose utilization and the one with best fermentation performance was selected. (illinois.edu)
  • The resultant yeast strain showed significantly improved cellobiose and xylose consumption ability and ethanol productivity in both shake-flask and bioreactor fermentation. (illinois.edu)
  • iii It was found that a small amount of glucose was accumulated during either cellobiose fermentation or cellobiose and xylose co-fermentation, which inevitably decreased the ethanol yield and productivity. (illinois.edu)
  • Papapetridis, Ioannis;Verhoeven, Maarten D;Wiersma, Sanne J;Goudriaan, Maaike;van Maris, Antonius J A;Pronk, Jack T 2018-05-15 00:00:00 Abstract Simultaneous fermentation of glucose and xylose can contribute to improved productivity and robustness of yeast-based processes for bioethanol production from lignocellulosic hydrolysates. (deepdyve.com)
  • Current strain engineering strategies for enabling pentose fermentation by S. cerevisiae typically yield strains that, in anaerobic batch cultures grown on sugar mixtures, preferentially ferment glucose, while xylose and/or arabinose are predominantly converted in a second, slower fermentation phase (Jansen et al.2017). (deepdyve.com)
  • Results We describe the development of a recombinant yeast system for the fermentation of cellulose and xylose, the most abundant pentose sugar in the hemicellulose fraction of biomass. (tcd.ie)
  • The initial metabolism of xylose by the engineered strains facilitated production of cellulases at fermentation temperatures. (tcd.ie)
  • Conclusions Reconstitution of complete enzymatic pathways for cellulose hydrolysis and xylose utilisation in S. pastorianus facilitates the co-fermentation of cellulose and xylose without the need for added exogenous cellulases and provides a basis for the development of a consolidated process for co-utilisation of hemicellulose and cellulose sugars. (tcd.ie)
  • Why the duration with the ointment water offers the easiest certain average cost of generic xylose patient from the instance for the young words from the inhibitory fermentation it would be earhest to explain. (kirkhopperfineart.com)
  • To enable fermentation of both hexose and pentose sugars present in plant biomass, many researchers have introduced eukaryotic D-xylose utilisation metabolic pathways into S. cerevisiae as these yeasts cannot utilise D-xylose. (sun.ac.za)
  • Simultaneous utilization of glucose and xylose was also seen during fermentation of corn-stover hydrolysate with a lipid content and coefficient of 39.2% and 0.15 g/g sugar, respectively. (biomedcentral.com)
  • Clearly, the mode of fermentation has a high impact on the xylose conversion by yeast in SSF. (biomedcentral.com)
  • The positive effects of glucose on xylose uptake make SSF an interesting process concept for co-fermentation. (biomedcentral.com)
  • However, the microbial fermentation of xylose, which is the principal pentose sugar in hemicellulose, is a limiting factor in developing such processes. (springeropen.com)
  • Adjusting the initial pH between 3.0 and 5.0 did not markedly influence xylose fermentation. (springeropen.com)
  • Efficient xylose utilisation by microorganisms is of importance to the lignocellulose fermentation industry. (sun.ac.za)
  • The aim of this work was to develop constitutive catabolite repression mutants in a xylose-utilising recombinant Saccharomyces cerevisiae strain and evaluate the differences in xylose consumption under fermentation conditions. (sun.ac.za)
  • Anaerobic batch fermentation in minimal medium with glucose-xylose mixtures and N-limited chemostats with varying sugar concentrations were performed. (sun.ac.za)
  • This study shows that a constitutive catabolite repressed mutant could be used to enhance the xylose consumption rate even in the presence of high glucose in the fermentation medium. (sun.ac.za)
  • Xylose fermentation in yeast has been a target of research for years, yet not all the factors that may affect xylose fermentation perfomance of yeast strains are known. (lu.se)
  • In this study, the mutant S. cerevisiae strain TMB 3400, which has good xylose fermentation properties, was compared with its parental strain to examine the factors behind the improved xylose utilization at protein level. (lu.se)
  • The most positive effect on xylose fermentation to ethanol was found by using the Y-R276H strain, expressing Ps XR R276H mutant and Ps XDH WT: 20 % increase of ethanol production and 52 % decrease of xylitol excretion, compared with the Y-WT strain expressing Ps XR WT and Ps XDH WT. (microbiologyresearch.org)
  • This yeast is one of several studied extensively for use in xylose fermentation. (wikipedia.org)
  • This can be accomplished either by native xylose fermenting yeasts such as Scheffersomyces Pichia stipitis or by metabolically engineered strains of Saccharomyces cerevisiae. (wikipedia.org)
  • This process would greatly benefit from recombinant Saccharomyces cerevisiae strains also able to ferment, besides the hexose sugar fraction, the pentose sugars, arabinose and xylose. (mendeley.com)
  • Xylose transport studies with xylose-utilizing Saccharomyces cerevisiae strains expressing heterologous and homologous permeases. (nih.gov)
  • In the present study, we modified xylose uptake properties of a recombinant xylose-utilizing yeast Saccharomyces cerevisiae by expression of heterologous and homologous permease-encoding genes. (nih.gov)
  • Glucose can be fermented to ethanol by yeast strains such as Saccharomyces cerevisiae, which, however, is unable to ferment the other major carbohydrate fraction, D-xylose. (osti.gov)
  • Metabolic engineering of Saccharomyces for bioconversion of D-xylose to D-xylonate, Metab. (freepatentsonline.com)
  • En av de stora utmaningarna är att denna råvara innehåller pentoser, framförallt xylos, vilka jästen Saccharomyces cerevisiae, inte kan jäsa. (lu.se)
  • Baker's yeast, Saccharomyces cerevisiae, has been engineered to ferment the pentose sugar xylose from lignocellulose to ethanol. (lu.se)
  • A collaborative led by researchers at the University of Illinois and including the Lawrence Berkeley National Laboratory, the University of California at Berkeley, Seoul National University and BP have engineered a strain of Saccharomyces cerevisiae -the common industrial yeast-to co-ferment glucose and xylose simultaneously to produce ethanol. (greencarcongress.com)
  • Tomas-Pejo, E., Lars, W. och Olsson, L. (2012) Effect of inhibitors present n lignocellulosic hydrolysates on evolved xylose fermenting Saccharomyces cerevisiae strains . (chalmers.se)
  • Tomas-Pejo2012, author={Tomas-Pejo, Elia and Lars, Weelin and Olsson, Lisbeth}, title={Effect of inhibitors present n lignocellulosic hydrolysates on evolved xylose fermenting Saccharomyces cerevisiae strains}, booktitle={34th Symposium for Biofuels and Chemicals. (chalmers.se)
  • A strain of Saccharomyces cerevisiae engineered for xylose utilization and formation of dicarboxylic acids was assessed and found rather tolerant to SSL even at acidic condi- tions. (dissertations.se)
  • Saccharomyces cerevisiae ferments hexoses efficiently but is unable to ferment xylose. (asm.org)
  • Engineering Saccharomyces pastorianus for the co-utilisation of xylose and cellulose from biomass. (tcd.ie)
  • Kricka, W., Fitzpatrick, J., T.C. James and U. Bond, Engineering Saccharomyces pastorianus for the co-utilisation of xylose and cellulose from biomass. (tcd.ie)
  • This work shows that a high degree of xylose conversion and high ethanol yields can be achieved in SSF of pretreated spruce with a xylose fermenting strain of Saccharomyces cerevisiae (TMB3400) at 7% and 10% water insoluble solids (WIS). (biomedcentral.com)
  • However, the most commonly used yeast species for bioethanol production, Saccharomyces cerevisiae , is unable to ferment xylose (Barnett 1976 ), and only a few species capable of efficiently fermenting this sugar, including Pachysolen tannophilus , Candida spp. (springeropen.com)
  • Xylose assimilation enhances the production of isobutanol in engineered Saccharomyces cerevisiae. (princeton.edu)
  • Bioconversion of xylose-the second most abundant sugar in nature-into high-value fuels and chemicals by engineered Saccharomyces cerevisiae has been a long-term goal of the metabolic engineering community. (princeton.edu)
  • A recombinant Saccharomyces cerevisiae strain transformed with xylose reductase (XR) and xylitol dehydrogenase (XDH) genes from Pichia stipitis ( Ps XR and Ps XDH, respectively) has the ability to convert xylose to ethanol together with the unfavourable excretion of xylitol, which may be due to intercellular redox imbalance caused by the different coenzyme specificity between NADPH-preferring XR and NAD + -dependent XDH. (microbiologyresearch.org)
  • Saccharophagus degradans Xylonic acid Xylose metabolism The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals (11th ed. (wikipedia.org)
  • However, the effectiveness of D-xylose metabolizing laboratory strains do not always reflect their metabolism abilities on raw xylose products in nature. (wikipedia.org)
  • Physiological and biochemical studies of T. mathranii, including extraction of intracellular metabolites and enzymes of the pentose phosphate pathway and glycolysis, revealed several bottlenecks in the D-xylose metabolism. (osti.gov)
  • Alff-Tuomala S, Salusjarvi L, Barth D, Oja M, Penttila M, Pitkanen JP, Ruohonen L, Jouhten P (2016) Xylose-induced dynamic effects on metabolism and gene expression in engineered Saccharomyes cerevisiae in anaerobic glucose-xylose cultures. (springer.com)
  • Conclusions: Engineering of yeast endogenous hexose transporters provides an effective strategy to construct glucose-insensitive xylose transporters that are well integrated in the carbon metabolism regulatory network, and that can be used for efficient lignocellulosic bioethanol production. (rug.nl)
  • Two novel endophytic yeast strains, WP1 and PTD3, isolated from within the stems of poplar ( Populus ) trees, were genetically characterized with respect to their xylose metabolism genes. (scielo.br)
  • The yeast's extremely slow metabolism of xylose also adds significantly to the cost of biofuels production. (greencarcongress.com)
  • Measurement of key metabolites and the activities of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. (dtu.dk)
  • Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression had been relieved. (dtu.dk)
  • Kinetic substituent effects have been used to examine the catalytic reaction profile of xylose reductase from the yeast Candida tenuis , a representative aldo/keto reductase of primary carbohydrate metabolism. (biochemj.org)
  • Yeast strains that had constitutive (mostly unregulated) control of xylose metabolism triggered pathways related to cell stress, starvation and DNA damage. (tufts.edu)
  • The sequential metabolism of xylose and cellulose generated an alcohol yield of 82% from the available sugars. (tcd.ie)
  • Xylose metabolism and cell growth were inhibited in fermentations carried out with acid-treated spent grain liquor, resulting in a 30% reduction in alcohol yield compared to fermentations carried out with mixed sugar substrates. (tcd.ie)
  • The candidate genes for the xylulokinase, xylose transporters, and the transcriptional regulator of xylose metabolism (XylR), were unambiguously assigned in all of the analyzed species based on the analysis of conserved chromosomal gene clustering and regulons. (biomedcentral.com)
  • The most significant changes detected by proteome analysis were the 6-10-fold increased levels of xylose reductase, xylitol dehydrogenase and transketolase (Tkl1) in the mutant, which is in accordance with previous knowledge about xylose metabolism in yeast. (lu.se)
  • However, this entrenched focus on ethanol has concealed the fact that many aspects of xylose metabolism favor the production of nonethanol products. (princeton.edu)
  • Its optimum growth pH is about 7.5 for the L. lactis, however strains such as the L.brevis xylose enzyme prefer a more alkaline environment. (wikipedia.org)
  • In attempts to generate S. cerevisiae strains that are able to ferment D-xylose the XYL1 and XYL2 genes of P. stipitis coding for the D-xylose reductase (XR) and xylitol dehydrogenase (XDH), respectively were introduced in S. cerevisiae by means of genetic engineering. (wikipedia.org)
  • The single-Hxt strains showed a biphasic growth mode on xylose, alike the Trxlt1 harboring strain. (nih.gov)
  • Xylose-utilising yeasts were screened to identify strains with high xylose transport capacity. (lu.se)
  • Among the fastest-growing strains in xylose medium, Candida intermedia PYCC 4715 showed the highest xylose transport capacity. (lu.se)
  • article{8c48c7f9-5e14-4ff0-b45d-825a3560e4ba, abstract = {Xylose-utilising yeasts were screened to identify strains with high xylose transport capacity. (lu.se)
  • Consequently, engineered xylose-fermenting yeast strains first utilize D-glucose before D-xylose can be transported and metabolized. (rug.nl)
  • High cell density fermentations with the recombinant strains showed that the XUT1 gene allowed ethanol production from xylose or xylose plus glucose as carbon sources, while the HXT2.6 permease produced both ethanol and xylitol, and the strain expressing the QUP2 gene produced mainly xylitol during xylose consumption. (sigmaaldrich.com)
  • These two strains, belonging to the species Rhodotorula graminis and R. mucilaginosa , respectively, utilize both hexose and pentose sugars, including the common plant pentose sugar, D-xylose. (scielo.br)
  • Our results revealed that for both strains, the gene expression is induced by D-xylose, and that in PTD3 the expression was not repressed by glucose in the presence of xylose. (scielo.br)
  • The new yeast strain is at least 20% more efficient at converting xylose to ethanol than other strains, making it the best xylose-fermenting strain reported in any study, according to Jin. (greencarcongress.com)
  • Most yeast strains that are engineered to metabolize xylose do so very slowly. (greencarcongress.com)
  • Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. (dtu.dk)
  • None of the recombinant strains grew on xylose. (asm.org)
  • Comparative studies of the growth behavior of the different mutant strains (deleted and retransformed xyr1 ) grown on various carbon sources pointed to the strongly reduced ability of the xyr1 deletion strain to utilize d -xylose and xylan. (asm.org)
  • Whole-genome sequencing of evolved strains identified mutations in HXK2, RSP5 and GAL83, whose introduction into a non-evolved xylose-fermenting S. cerevisiae strain improved co-consumption of xylose and glucose under aerobic and anaerobic conditions. (deepdyve.com)
  • Xsp8, one of the engineered strains, was capable of growing on up to 180 g L -1 of xylose. (biomedcentral.com)
  • The strains were grown aerobically in synthetic complete medium with xylose as the sole carbon source. (sun.ac.za)
  • The results of the proteome analysis were in good agreement with a parallel study in which rationally designed overexpression of XR, XDH and the non-oxidative pentose phosphate pathway resulted in similar improvement in xylose utilization, which demonstrates the usefulness of proteome analysis for the identification of target genes for further metabolic engineering strategies in industrial yeast strains. (lu.se)
  • Three strains (DMKU-XE11 T , DMKU-XE15 and DMKU-XE20) representing a single novel anamorphic and d -xylose-fermenting yeast species were obtained from three peat samples collected from Khan Thulee peat swamp forest in Surat Thani province, Thailand. (microbiologyresearch.org)
  • In a mutant yeast strain with the main seven hexose transporter genes deleted, and engineered for xylose utilization, we screened an expression cDNA library of the filamentous fungus Trichoderma reesei (Hypocrea jecorina) for enhanced growth on xylose plates. (nih.gov)
  • The mutants W23F and W23Y catalysed NADH-dependent reduction of xylose with only 4 and 1% of the wild-type efficiency (kcat/K(m)) respectively, but improved the wild-type selectivity for utilization of ketones, relative to xylose, by factors of 156 and 471 respectively. (unboundmedicine.com)
  • The different stoichiometries of the three xylose utilization pathways may allow engineering of tailored chassis for valuable bioproduct synthesis. (frontiersin.org)
  • However, glucose repression limits efficient ethanol production because glucose in lignocellulosic hydrolysates inhibits xylose and other sugars' utilization. (illinois.edu)
  • Nevertheless, homology searches failed to recognize all the genes for the complete xylose and xyloside utilization pathway in most of them. (biomedcentral.com)
  • A comparative genomic approach was used to reconstruct the xylose and xyloside utilization pathway and analyze its regulatory mechanisms in 24 genomes of the Firmicutes. (biomedcentral.com)
  • XylR regulons were reconstructed by identification and comparative analysis of XylR-binding sites upstream of xylose and xyloside utilization genes. (biomedcentral.com)
  • This study provided comprehensive insights to the xylose catabolism and its regulation in diverse Firmicutes bacteria especially Clostridia species, and paved ways for improving xylose utilization capability in C. acetobutylicum by genetic engineering in the future. (biomedcentral.com)
  • In B. subtilis , the genes involved in the xylose and xyloside utilization pathway are clustered into two operons, xylAB and xynTB (Figure 2 ). (biomedcentral.com)
  • Thus, identification of microorganisms capable of efficient and simultaneous utilization of both glucose and xylose is pivotal to improving this process. (biomedcentral.com)
  • In shake-flask cultures with different initial glucose:xylose ratios, glucose and xylose were consumed simultaneously at rates roughly proportional to their individual concentrations in the medium, leading to complete utilization of both sugars at the same time. (biomedcentral.com)
  • Utilization of glucose and xylose simultaneously is an important process in the utilization of lignocellulosic biomass and related raw materials as the carbon sources, in order to reduce the costs of microbial lipid technology. (biomedcentral.com)
  • Initial glucose present in pretreated spruce decreases the xylose utilization by yeast, due to competitive inhibition of sugar transport. (biomedcentral.com)
  • Prefermentation and fed-batch operation, both separately and in combination, improved xylose utilization. (biomedcentral.com)
  • Up to 77% xylose utilization and 85% of theoretical ethanol yield (based on total sugars), giving a final ethanol concentration of 45 g L -1 , were obtained in fed-batch SSF at 10% WIS when prefermentation was applied. (biomedcentral.com)
  • In particular, the efficient microbial utilization of xylose, which is the principal pentose sugar of the hemicellulose component of lignocellulosic biomass (Gírio et al. (springeropen.com)
  • Cloning novel sugar transporters not previously identified in the S. stipitis genome using an hxt-null S. cerevisiae strain with a high xylose-utilizing pathway provides novel promising target genes for improved lignocellulosic ethanol production by yeasts. (sigmaaldrich.com)
  • This pathway is also called the "Xylose Reductase-Xylitol Dehydrogenase" or XR-XDH pathway. (wikipedia.org)
  • Xylose reductase (XR) and xylitol dehydrogenase (XDH) are the first two enzymes in this pathway. (wikipedia.org)
  • The Weimberg pathway is an oxidative pathway where the D-xylose is oxidized to D-xylono-lactone by a D-xylose dehydrogenase followed by a lactonase to hydrolyze the lactone to D-xylonic acid. (wikipedia.org)
  • Then, a new route for glycolate production was established in E . coli by introducing NAD + -dependent xylose dehydrogenase ( xdh ) and xylonolactonase ( xylC ) from Caulobacter crescentus . (springer.com)
  • This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus , represents an excellent alternative to the manual phloroglucinol reaction. (hindawi.com)
  • Bacteria such as Pseudomonas, Gluconobacter and Caulobacter are capable of producing dehydrogenase for converting D-xylose to D-xylonolactone, which can be hydrolyzed naturally or by an enzyme to produce D-xylonic acid. (freepatentsonline.com)
  • An hxt-null S. cerevisiae strain, lacking the major hexose transporters (hxt1Δ-hxt7Δ and gal2Δ) but having high xylose reductase, xylitol dehydrogenase and xylulokinase activities, was transformed with a genomic DNA library from S. stipitis. (sigmaaldrich.com)
  • The xylose reductase (XYL1) and xylitol dehydrogenase (XYL2) genes were cloned and characterized. (scielo.br)
  • First, D-xylose is reduced by a NADPH/NADH-linked xylose reductase (XR) to xylitol, whereupon the latter is oxidized to xylulose by an NAD-linked xylitol dehydrogenase (XDH) (Bruinenberg and van Dijken, 1983). (scielo.br)
  • The β-D-xylose is oxidised by NAD + to D-xylonic acid in the presence of β-xylose dehydrogenase (β-XDH) at pH 7.5 (2). (megazyme.com)
  • One Unit of xylose dehydrogenase is defined as the amount of enzyme required to produce one µmole of NADH from NAD + per minute at 25 o C. (megazyme.com)
  • High purity recombinant Xylose dehydrogenase + Xylose mutarotase for use in research, biochemical enzyme assays and in vitro diagnostic analysis. (megazyme.com)
  • In this study, we demonstrate enzymatic conversion of xylose with simultaneous cofactor regeneration using co-immobilized xylose dehydrogenase and alcohol dehydrogenase. (megazyme.com)
  • The xylose reductase, xylitol dehydrogenase and xylulose kinase genes were co-expressed with genes encoding for the three classes of T. reesei cellulases, namely endoglucanase (EG2), cellobiohydrolysase (CBH2) and β-glucosidase (BGL1). (tcd.ie)
  • XR catalyze the formation of xylitol from D-xylose and XDH the formation of D-xylulose from xylitol. (wikipedia.org)
  • This enzyme catalyze the direct formation of D-xylulose from D-xylose. (wikipedia.org)
  • d -xylose is initially converted to d -xylulose by the catalysis of different enzymes in microorganisms. (springer.com)
  • In some yeasts and fungi, conversion of D-xylose to D-xylulose more often occurs by two enzymatic steps. (scielo.br)
  • The alcohol yield was influenced by the concentration of xylose in the medium and was significantly improved by the additional expression of a gene encoding for xylulose kinase. (tcd.ie)
  • D-Xylose is finally transformed to the common metabolic intermediate xylulose 5-phosphate. (biomedcentral.com)
  • In bacteria, the transformation of D-xylose to xylulose 5-P is catalyzed via consecutive isomerization to D-xylulose and phosphorylation reactions (Figure 1 ). (biomedcentral.com)
  • New routes for the conversion of xylose to glycolate were explored. (springer.com)
  • The one-pot conversion of xylose into γ-gammavalerolactone in 2-propanol over bifunctional Zr-Al-Beta zeolites, prepared via a post-synthetic route, was optimized in terms of both catalyst synthesis and reaction conditions. (rsc.org)
  • Overexpression of aceA and ghrA and deletion of aceB in Escherichia coli were examined for glycolate production from xylose, but the conversion was initially ineffective. (springer.com)
  • A new route for glycolate production from xylose was established, and an engineered strain Q2742 was constructed from this new explored pathway. (springer.com)
  • However, ethanol production from xylose is slow and often incomplete. (lu.se)
  • Reduction of xylose by catalytic hydrogenation produces the sugar substitute xylitol. (wikipedia.org)
  • XR reduces D-xylose to xylitol using NADH or NADPH. (wikipedia.org)
  • Barbosa MF, de Medeiros MB, de Mancilha IM, Schneider H, Lee H (1988) Screening of yeasts for production of xylitol fromd-xylose and some factors which affect xylitol yield in Candida guilliermondii . (springer.com)
  • D50A showed 31 and 18% of the wild-type catalytic-centre activities for xylose reduction and xylitol oxidation respectively, consistent with a decrease in the rates of the chemical steps caused by the mutation, but no change in the apparent substrate binding constants and the pattern of substrate specificities. (unboundmedicine.com)
  • The present invention relates to a method of producing xylitol using a hydrolysate containing xylose and arabinose prepared from a byproduct of a tropical fruit biomass. (freepatentsonline.com)
  • The two major chemicals of interest that can be produced from D-xylose by yeasts are ethanol and xylitol. (scielo.br)
  • An unspecific aldose reductase (AR) capable of reducing xylose to xylitol has been identified in S . cerevisiae . (asm.org)
  • The aim of this study was to increase D-xylose utilisation and lower the xylitol production found with the eukaryotic pathway, thus redirecting carbon to the increased production of ethanol. (sun.ac.za)
  • Unfortunately no mutant superior to the parental strain with respect to D-xylose utilisation, lowered xylitol production and improved ethanol production was obtained. (sun.ac.za)
  • A cluster of three genes involved in D-xylose catabolism (viz. (tudelft.nl)
  • xylose genes) in Lactobacillus pentosus has been cloned in Escherichia coli and characterized by nucleotide sequence analysis. (tudelft.nl)
  • The cloned genes represent functional xylose genes since they are able to complement the inability of a L. casei strain to ferment D-xylose. (tudelft.nl)
  • NMR analysis confirmed that 13C-xylose was converted into 13C-acetate in L. casei cells transformed with L. pentosus xylose genes but not in untransformed L. casei cells. (tudelft.nl)
  • Four plasmids allowing growth on xylose contained three genes encoding sugar transporters: the previously characterized XUT1 permease, and two new genes (HXT2.6 and QUP2) not previously identified as xylose transporters. (sigmaaldrich.com)
  • The expression of the corresponding genes is controlled by the dedicated transcriptional activator XlnR and its inducer, d -xylose ( 58 ). (asm.org)
  • Genes encoding enzymes of the Weimberg pathway, an orthogonal xylose degradation pathway, were introduced in S. cerevisiae. (dissertations.se)
  • Regulation of the respective genes via Xyr1 is not affected by the substances mediating induction (xylose, xylobiose, and sophorose) and is indispensable for all modes of gene expression (basal, derepressed, and induced). (asm.org)
  • Taking a different approach, the researchers took a set of regulatory genes, called a GAL regulon, that normally processes galactose - a favorite on the yeast menu of nutrients - and replaced some of the genes with those that become activated by, and direct the breakdown of, xylose. (tufts.edu)
  • Firstly S. cerevisiae transformed with eukaryotic XR and XDH genes were subjected to random mutagenesis and selection for improved D-xylose utilisation. (sun.ac.za)
  • We further demonstrated that in addition to the introduction and the concomitant expression of heterologous xylA and xylB genes, there is another molecular target in the R. opacus genome which fully enables the functionality of xylA and xylB genes to generate the robust xylose-fermenting strain capable of efficiently producing TAGs at high xylose concentrations. (biomedcentral.com)
  • Xylose is also the first saccharide added to the serine or threonine in the proteoglycan type O-glycosylation, and, so, it is the first saccharide in biosynthetic pathways of most anionic polysaccharides such as heparan sulfate and chondroitin sulfate. (wikipedia.org)
  • There are at least four different pathways for the catabolism of D-xylose: An oxido-reductase pathway is present in eukaryotic microorganisms. (wikipedia.org)
  • Another experiment comparing the two D-xylose metabolizing pathways revealed that the XI pathway was best able to metabolize D-xylose to produce the greatest ethanol yield, while the XR-XDH pathway reached a much faster rate of ethanol production. (wikipedia.org)
  • Different pathways can be introduced in S. cerevisiae to provide arabinose and xylose utilisation. (mendeley.com)
  • Moreover, in the case of yeast, D-xylose may provide a better feedstock for the production of bioproducts other than ethanol, because the relevant pathways are not subject to glucose-dependent repression. (springer.com)
  • Therefore xylose is involved in the biosythetic pathways of most anionic polysaccharides such as heparan sulphate and chondroitin sulphate. (hmdb.ca)
  • The goal of this study is to map the metabolic pathways of poorly understood bacterial phytopathogen, Xanthomonas oryzae (Xoo) BXO43 fed with plant mimicking media XOM2 containing glutamate, methionine and either 40% [ 13 C 5 ] xylose or 40% [ 13 C 6 ] glucose. (mdpi.com)
  • Through reduced overall metabolic flux, a more respiratory nature of consumption, and evading glucose signaling pathways, the bioconversion of xylose can be more amenable to redirecting flux away from ethanol towards the desired target product. (princeton.edu)
  • Results: We have used an evolutionary engineering approach that depends on a quadruple hexokinase deletion xylose-fermenting S. cerevisiae strain to select for growth on D-xylose in the presence of high D-glucose concentrations. (rug.nl)
  • Deletion of the GRE3 gene combined with expression of the xylA gene from T . thermophilus on a replicative plasmid generated recombinant xylose utilizing S . cerevisiae strain TMB3102, which produced ethanol from xylose with a yield of 0.28 mmol of C from ethanol/mmol of C from xylose. (asm.org)
  • This bacterium was mistakenly classified as a L. plantarum, which normally grows on the sugar L-arabinose, and rarely grown on D-xylose. (wikipedia.org)
  • When finally hydrolyzed, they yield arabinose and xylose , respectively. (dictionary.com)
  • However, the complexity of these polymeric substrates and the presence of several types of carbohydrates (glucose, xylose, mannose, galactose, arabinose) require additional treatment to release the useful carbohydrates and ferment the major carbohydrates fractions. (osti.gov)
  • In addition, the present invention relates to an active carbon produced by carbonization and activation of a hydrolysate remainder of a tropical fruit shell, the byproduct of xylose and arabinose production, at a certain temperature and a preparation method of the same. (freepatentsonline.com)
  • Activity of the Weimberg pathway was found during growth on both xylose and arabinose, but not on glucose. (dissertations.se)
  • Mixtures of the α-L-arabinofuranosidases, with specific action on AXOS, have been combined with β-xylosidase and β-xylanase to obtain an optimal mixture for hydrolysis of arabinoxylan to L-arabinose and D-xylose. (megazyme.com)
  • The permeability characteristics of D - and L -xylose and D - and L -arabinose have been compared in isolated intact rat diaphragm muscle preparations, in the absence and presence of exogenous insulin. (rupress.org)
  • L -Xylose and D -arabinose distribute in 50 per cent of the intracellular water, whereas D -xylose and L -arabinose distribute in 80 per cent of the cell water. (rupress.org)
  • A significant lag period was observed before the insulin effect upon the penetration of L -xylose and D -arabinose was evident whereas the effect upon D -xylose and L -arabinose was rapid. (rupress.org)
  • In dinitrophenol-treated tissues, in which all permeability processes are irreversibly damaged and in which sucrose and pentoses penetrate into most of the cell water, the entry rate of pentoses and sucrose is initially similar but subsequently D -xylose and L -arabinose penetrate more rapidly than their corresponding optical isomers. (rupress.org)
  • However, during a long liquid culture of the strain carrying the cDNA clone, adaptive mutations apparently occurred in the host, which led to growth on xylose but not on glucose. (nih.gov)
  • The xylT gene was functionally expressed in Lactobacillus plantarum 80, a strain which lacks proton motive force-linked D-xylose transport activity. (tudelft.nl)
  • The constructed engineered strain Q2562 produced 28.82 ± 0.56 g/L glycolate from xylose with 0.60 ± 0.01 g/L/h productivity and 0.38 ± 0.07 g/g xylose yield. (springer.com)
  • The final engineered strain Q2742 produced 43.60 ± 1.22 g/L glycolate, with 0.91 ± 0.02 g/L/h productivity and 0.46 ± 0.03 g/g xylose yield. (springer.com)
  • The ratio of xylose/glucuronic acid/mannose ranges from 1:1:3 to 4:1:3, depending on the strain, and this variation is likely to be responsible for differences between cryptococcal serotypes that have distinct host range and growth characteristics ( 6 ). (pnas.org)
  • The pathway of UDP-Xyl synthesis is of particular interest in C. neoformans , because of the abundant and strain-specific modification of glucuronoxylomannan and galactoxylomannan with xylose. (pnas.org)
  • This knowledge makes way for physiologicl and genetic engineering of this strain to improve the ethanol yield and productivity at high concentration of D-xylose. (osti.gov)
  • Agrawal M, Mao Z, Chen RR (2011) Adaptation yields a highly efficient xylose-fermenting Zymomonas mobilis strain. (springer.com)
  • The new yeast strain simultaneously converts cellobiose (a precursor of glucose) and xylose to ethanol just as quickly as it can ferment either sugar alone. (greencarcongress.com)
  • A mutant strain of C. neoformans that cannot transport xylose precursors into the secretory compartment is severely attenuated in virulence in mice yet surprisingly is not cleared. (asm.org)
  • The xylose consumption rate was enhanced by 42% to 0.68 g L-1 h-1 in the engineered laboratory strain, and a maximum ethanol productivity of 0.49 g L-1 h-1was obtained, with no obvious glucose repression phenomenon observed. (illinois.edu)
  • The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. (dtu.dk)
  • This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. (dtu.dk)
  • It could be demonstrated that the uptake of d -xylose into the fungal cell is uninfluenced in the Δ xyr1 strain. (asm.org)
  • Laboratory evolution of this strain in serial batch cultures on glucose-xylose mixtures yielded mutants that rapidly co-consumed the two sugars. (deepdyve.com)
  • Combined deletion of HXK2 and introduction of a GAL83G673T allele yielded a strain with a 2.5-fold higher xylose and glucose co-consumption ratio than its xylose-fermenting parental strain. (deepdyve.com)
  • We successfully engineered a R. opacus strain that is capable of completely utilizing high concentrations of xylose or mixed xylose/glucose simultaneously, and substantiated its suitability for TAG production. (biomedcentral.com)
  • In this study, we found that the oleaginous yeast strain Trichosporon cutaneum AS 2.571 assimilated glucose and xylose simultaneously, and accumulated intracellular lipid up to 59 wt% with a lipid coefficient up to 0.17 g/g sugar, upon cultivation on a 2:1 glucose/xylose mixture in a 3-liter stirred-tank bioreactor. (biomedcentral.com)
  • The xylose-utilizing strain of S. cerevisiae used in this work, TMB3400 [ 15 ], has previously been used for SSF of lignocellulosic materials rich in xylose. (biomedcentral.com)
  • Here, a strain of the white rot basidiomycete Trametes versicolor that was capable of efficiently fermenting xylose was newly isolated and characterized. (springeropen.com)
  • This strain, designated KT9427, was capable of assimilating and converting xylose to ethanol under anaerobic conditions with a yield of 0.44 g ethanol per 1 g of sugar consumed. (springeropen.com)
  • Constitutive catabolite repressed strain YCR17 grew four-fold better on xylose in aerobic conditions than the control strain YUSM. (sun.ac.za)
  • Proteome analysis of the xylose-fermenting mutant yeast strain TMB 3400. (lu.se)
  • This typically occurs under oxygen limiting conditions or when non-native xylose fermenting yeasts are engineered with the oxido-reductase pathway. (wikipedia.org)
  • The complete pathway was not functional and growth on xylose was not obtained. (dissertations.se)
  • In the cultivations on single carbon sources, it was demonstrated that xylose acted as a carbon catabolite repressor (xylose cultivations), while the enzymes in the xylose utilisation pathway were also subject to repression in the presence of glucose (glucose cultivations). (dtu.dk)
  • Transcriptional analysis of the xyl1 ( d -xylose reductase 1-encoding) gene as well as measurements of corresponding enzymatic activities gave evidence that Xyr1 takes part in the control of the fungal d -xylose pathway, in particular in the regulation of d -xylose reductase. (asm.org)
  • The most significant differences were found to be associated with the CAZymes, as well as specific up regulation of some key components of the pentose phosphate pathway in the presence of xylose and xylan. (biomedcentral.com)
  • In this report, we show that coupling xylose consumption via the oxidoreductive pathway with a mitochondrially-targeted isobutanol biosynthesis pathway leads to enhanced product yields and titers as compared to cultures utilizing glucose or galactose as a carbon source. (princeton.edu)
  • It is desirable to ferment D-xylose to ethanol. (wikipedia.org)
  • S. cerevisiae on the other hand can not ferment D-xylose to ethanol. (wikipedia.org)
  • The need for a microorganism able to ferment D-xylose is therefore apparent. (osti.gov)
  • This ability to utilise D-xylose represents a significant step for recombinant S. cerevisiae to potentially ferment D-xylose for bioethanol. (sun.ac.za)
  • with xylose utilisation occurring only after glucose was depleted. (dtu.dk)
  • The new transporter homologue, Trxlt1 thus appears to code for a protein specific for xylose uptake. (nih.gov)
  • This could be attributed to mutations at N367 in the endogenous chimeric Hxt36 transporter, causing a defect in D-glucose transport while still allowing specific uptake of D-xylose. (rug.nl)
  • Due to the lack of a xylose uptake system, B. subtilis is unable to grow with xylose as a sole carbon source [ 15 ]. (biomedcentral.com)
  • Prefermentation enhances xylose uptake most likely because of the reduced transport inhibition, in both batch and fed-batch operation. (biomedcentral.com)
  • At higher WIS contents, however, the concentrations of inhibitors and hexoses (inhibiting xylose uptake) will be higher. (biomedcentral.com)
  • Therefore, the glucose concentration must be low in order to obtain efficient xylose uptake. (biomedcentral.com)
  • Mannose, present in spruce hydrolyzate, is also known to inhibit xylose uptake. (biomedcentral.com)
  • It is less common in native xylose fermenting yeasts that have biochemical mechanisms for regenerating NAD under oxygen limitation. (wikipedia.org)
  • To overcome these bottlenecks, we engineered yeasts to co-ferment mixtures of xylose and cellobiose. (greencarcongress.com)
  • Yeasts altered to take up xylose is that they will suck up all the glucose in a mixture before they will touch the xylose, Jin said. (greencarcongress.com)
  • 2005 ). As a biocatalyst for the efficient conversion of lignocellulosic biomass into ethanol it is preferable to utilize a microbe that possesses the ability to ferment various types of carbohydrates, which is a characteristic not observed in the above mentioned xylose-fermenting yeasts, ascomycetes and zygomycetes. (springeropen.com)
  • Excessive levels of carbon dioxide mean that there are high levels of anaerobic bacteria in the intestines breaking down the xylose. (thefreedictionary.com)
  • These two modifications decreased the time required for full sugar conversion in anaerobic bioreactor batch cultures, grown on 20 g L−1 glucose and 10 g L−1 xylose, by over 24 h. (deepdyve.com)
  • In 2014 a low-temperature 50 °C (122 °F), atmospheric-pressure enzyme-driven process to convert xylose into hydrogen with nearly 100% of the theoretical yield was announced. (wikipedia.org)
  • Under these optimized reaction conditions, Zr-Al-Beta catalyst provides a GVL yield from xylose ( ca. 34%) after only 10 h. (rsc.org)
  • When utilizing the recombinant E. coli prepared by the method of the present invention, it is possible to produce D-xylonic acid from D-xylose with high yield while reducing production cost using sole carbon source. (freepatentsonline.com)
  • High yield production of D-xylonic acid from D-xylose using engineered Escherichia coli. (freepatentsonline.com)
  • The natural succinic acid producing bacterium Actinobacillus succinogenes was found able to produce succinate from a xylose rich synthetic model medium mimicking sugar com- position in SSL, at a titer of 31 g L-1 and yield of 0.71 g g-1. (dissertations.se)
  • When only cellulase is present, glucose and xylose yield were measured by Raman spectroscopy to be 32 ± 4 and 7.0 ± 0.8 mg mL(-1), respectively. (rjlg.com)
  • When both cellulase and hemicellulase were present, xylose yield increased to 18.0 ± 0.5 mg mL(-1). (rjlg.com)
  • and thermophilic biogas plants, paper pulp industries and brewery waste, were examined for production of ethanol from D-xylose and wet-oxidized hemicellulose hydrolysate. (osti.gov)
  • Additionally, a Raman spectroscopy multi-peak fitting method is presented to simultaneously measure glucose and xylose concentration in hydrolysate. (rjlg.com)
  • Bioconversion of water-hyacinth (Eichhornia crassipes) hemicellulose acid hydrolysate to motor fuel ethanol by xylose-fermenting yeast. (semanticscholar.org)
  • Xsp8 grown in batch-cultures derived from unbleached kraft hardwood pulp hydrolysate containing 70 g L -1 total sugars was able to completely and simultaneously utilize xylose and glucose present in the lignocellulosic feedstock, and yielded 11.0 g L -1 of TAGs as fatty acids, corresponding to 45.8% of the cell dry weight. (biomedcentral.com)
  • Furthermore, of a number of sugars tested, only 6-deoxy-D-glucose inhibited the transport of D-xylose by XylT competitively, with a K(i) of 220 μM. (tudelft.nl)
  • Hemicellulose consists primarily of pentose sugars, joined together in a polysaccharide chain with D-xylose as the most abundant component. (tudelft.nl)
  • In order to avoid competition with food and feed production it is desirable to use hydrolysates of lignocellulosic feedstocks which often not only contain hexose sugars but also pentoses, out of which xylose is the most common. (dissertations.se)
  • Our study applied this approach to xylose, but it suggests a broader principle - adapting native regulons for the efficient assimilation of other non-native sugars and nutrients," said Nair. (tufts.edu)
  • The amount of d-xylose that comes out in your urine over the next 5 hours will be measured. (medlineplus.gov)
  • The amount of D-xylose in urine and blood samples is measured before and after you drink a D-xylose solution. (wellspan.org)
  • Normal values depend on the amount of D-xylose administered. (drugster.info)
  • Moreover, the regulatory mechanisms of xylose catabolism in many Firmicutes except Bacillus spp. (biomedcentral.com)
  • Xylose in the urine is a biomarker for the consumption of apples and other fruits. (hmdb.ca)
  • The Hxt36-N367A variant transports D-xylose with a high rate and improved affinity, enabling the efficient co-consumption of D-glucose and D-xylose. (rug.nl)
  • Laboratory evolution for forced glucose-xylose co-consumption enables identification of mutations. (deepdyve.com)
  • In addition to growth on xylan, the simultaneous consumption of two important lignocellulose constituents, cellobiose and xylose was also demonstrated. (biomedcentral.com)
  • Efficient lipid production with simultaneous consumption of glucose and xylose was achieved in this study. (biomedcentral.com)
  • In culture medium containing low yeast extract concentrations, xylose consumption and ethanol productivity were enhanced. (springeropen.com)
  • YCR17 exhibited a faster xylose consumption rate than YUSM under high glucose conditions in nitrogen-limited chemostat cultivations. (sun.ac.za)
  • High capacity xylose transport in Candida intermedia PYCC4715. (lu.se)
  • The primary structure of the aldose xylose reductase from Candida tenuis (CtAR) is shown to be 39% identical to that of human aldose reductase (hAR). (unboundmedicine.com)
  • Xylose is the main building block for the hemicellulose xylan, which comprises about 30% of some plants (birch for example), far less in others (spruce and pine have about 9% xylan). (wikipedia.org)
  • In addition to glucose, the pentose xylose is a dominant building block in hemicellulose. (frontiersin.org)
  • After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. (hindawi.com)
  • This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine. (hindawi.com)
  • Cryptococcus neoformans is a fungal pathogen that kills almost 200,000 people each year and is distinguished by abundant and unique surface glycan structures that are rich in xylose. (asm.org)
  • One example of such a feedstock is spent sulphite liquor (SSL), a side stream from sulphite pulping of Eucalyptus, which is rich in xylose. (dissertations.se)
  • It is not found in a free state but in the form of xylan, a polysaccharide made up of D-xylose units and occurring in association with cellulose. (sciencephoto.com)
  • The polysaccharide xylan, which is closely associated with cellulose, consists practically entirely of d-xylose. (hmdb.ca)
  • This catalysis was applied as a solid acid catalyst for the heterogeneous catalytic transformations of xylose and xylan into furfural in the bio-based 2-methyltetrahydrofuran/H 2 O biphasic system. (mdpi.com)
  • Their catalytic performance for xylose and xylan into furfural was also investigated. (mdpi.com)
  • The reaction parameters such as the initial xylose and xylan concentration, the amounts of catalyst, the organic-to-aqueous phase volume ratio, the reaction temperature and time were studied to optimize the reaction conditions. (mdpi.com)
  • The substitution of water by the saturated NaCl solution in the aqueous phase also had an important effect on the xylose and xylan conversion. (mdpi.com)
  • Depolymerization of xylan and xyloglucan produces β- and α-xylosides, respectively, that are transported into the cell and further degraded into D-xylose [ 9 ]. (biomedcentral.com)
  • It is therefore ges in gene and gene product expression during growth of C. termitidis on cellobiose, xylose, xylan, and α-cellulose. (biomedcentral.com)
  • Bioconversion of D-xylose to D-xylonate with Kluyveromyces lactis", (2011) Elsevier Inc. (freepatentsonline.com)
  • The bioconversion of xylose, which is the second most abundant sugar present after glucose in lignocellulosic biomass, is important for the development of cost effective bioprocesses to fuels. (biomedcentral.com)
  • In the isomerization of xylose, crystal data has shown that xylose sugar binds to the enzyme in an open chain conformation. (wikipedia.org)
  • Xylose, also known as D-xylose, is a type of sugar that is normally easily absorbed by the intestines. (medlineplus.gov)
  • For 24 hours before the test, you will need to not eat foods high in a type of sugar known as pentose, which is similar to xylose. (medlineplus.gov)
  • D-xylose absorption is a laboratory test to check how well the intestines absorb a simple sugar (D-xylose). (medlineplus.gov)
  • You will be asked to drink 8 ounces (240 ml) of water that contains 25 grams of a sugar called d-xylose. (medlineplus.gov)
  • Xylose or wood sugar is an aldopentose - a monosaccharide containing five carbon atoms and including an aldehyde functional group. (bionity.com)
  • One cDNA clone with significant homology to fungal sugar transporters was obtained, but when the clone was retransformed into the host, it did not support significant growth on xylose. (nih.gov)
  • Xylose is a sugar first isolated from wood. (lookchem.com)
  • The D-xylose absorption test measures the level of D-xylose, a type of sugar, in a blood or urine sample. (wellspan.org)
  • For 24 hours before a D-xylose test, do not eat foods high in pentose, a sugar similar to D-xylose. (wellspan.org)
  • d -Xylose is the second most abundant sugar in nature and accounts for 18-30% of sugar in lignocellulose. (springer.com)
  • Ileal digestibility and urinary excretion of D-xylose and associated effects of this pentose sugar on ileal and faecal digestibility of dry matter (DM), organic matter (OM), gross energy (GE) and nitrogen were studied in pigs. (tudelft.nl)
  • D-xylose was given at dietary inclusion levels of 100 and 200 g/kg, and the control sugar, D-glucose, at a rate of 200 g/kg diet. (tudelft.nl)
  • Polarised light micrograph of crystals of wood sugar, known as xylose (D-xylose). (sciencephoto.com)
  • Xylose is a pentose sugar widely distributed in plants. (sciencephoto.com)
  • UDP-xylose is a sugar donor required for the synthesis of diverse and important glycan structures in animals, plants, fungi, and bacteria. (pnas.org)
  • UDP-xylose (UDP-Xyl) is an important nucleotide sugar required for the synthesis of numerous glycoconjugates. (pnas.org)
  • D-xylose is the second most abundant sugar in these hydrolysates. (springer.com)
  • Xylose is the first sugar added to serine or threonine residues during proteoglycan type O-glycosylation. (hmdb.ca)
  • xylose is a five-carbon sugar that has been much more difficult to utilize in ethanol production. (greencarcongress.com)
  • While S. cerevisiae is very good at utilizing glucose, a building block of cellulose and the primary sugar in plants, it cannot use xylose, a secondary but significant component of the lignocellulose that makes up plant stems and leaves. (greencarcongress.com)
  • Xylose is a wood sugar, a five-carbon sugar that is very abundant in lignocellulosic biomass but not in our food. (greencarcongress.com)
  • However, xylose is a sugar derived from the otherwise indigestible parts of plant material. (tufts.edu)
  • Samyang Corporation (CEO: President Moon Sung-hwan) will launch two types of TRUSWEET Xylose Sugar which has the same sweetness as sugar and lowers the absorption of sugar, under the premium sugar brand name TRUSWEET. (samyang.com)
  • Xylose, a type of sugar existing in various plants, lowers the absorption of sugar by inhibiting sucrase in the human body. (samyang.com)
  • When problems with absorption occur, D-xylose is not absorbed by the intestines, and its level in blood and urine is low. (wellspan.org)
  • Oral D-xylose absorption tests before and 7 days after HDMTX were carried out to evaluate intestinal absorption. (nih.gov)
  • Although we observed no difference of HDMTX-induced toxicity, including hematological, dermatological, systemic, and other toxicities, between groups, the D-xylose absorption test was significantly better in-group 1 ( p=0.030). (nih.gov)
  • The product of hydrolysis appears, therefore, to be xylose or a closely related derivative. (dictionary.com)
  • Response surface methodology (RSM), based on a 2 2 full factorial design, evaluated the moisture effects in recovering xylose by diethyloxalate (DEO) hydrolysis. (usda.gov)
  • The mathematical statistical model showed that xylose recovery increases during DEO corn stover acid hydrolysis as the corn stover moisture level increases. (usda.gov)
  • The corn stover moisture was an important variable to improve xylose recovery by DEO acid hydrolysis. (usda.gov)
  • In this particular breakdown process, these enzymes cause hydrolysis to smaller, soluble oligo- and monosaccharides which finally either act directly as low-molecular-weight inducer substances (e.g., xylobiose and xylose) ( 29 , 53 ) or are converted to their respective inducers (e.g., sophorose) via the transglycosylation activity of some of these enzymes ( 46 ). (asm.org)
  • High xylose intake on the order of approximately 100g/kg of animal body weight is relatively well tolerated in pigs, and in a similar manner to results from human studies, a portion of the xylose intake is passed out in urine undigested. (wikipedia.org)
  • In another approach, bacterial xylose isomerases have been introduced into S. cerevisiae. (wikipedia.org)
  • Therefore, the capability to efficiently metabolize xylose is a desirable attribute of microorganisms for optimizing the economics of lignocellulose-based bio-refinery processes. (springer.com)
  • However, R. opacus PD630 does not metabolize xylose. (biomedcentral.com)
  • Total xylose amount determined in urine and xylose concentration in blood represent a measure of total lactase activity in vivo [ 6 , 9 - 11 ]. (hindawi.com)
  • The maximum xylose recovery by the response surface methodology was achieved employing both DEO concentration and corn stover moisture at near their highest levels area. (usda.gov)
  • Experimentally, a maximum xylose recovery (81.2%) was achieved by using initial corn stover moisture of 60% and a DEO concentration of 4% w/w. (usda.gov)
  • The modelization of the catalytic system through experimental design methodology allowed to identify the optimal values of the most influential reaction conditions: temperature 190 °C, catalyst loading 15 g L −1 , and starting xylose concentration 30.5 g L −1 . (rsc.org)
  • Effect of xylose and nutrients concentration on ethanol production by a newly isolated extreme thermophilic Thermoanaerobacter sp. (dtu.dk)
  • Southern hybridization performed with the Lactobacillus pentosus xylR gene (encoding the D-xylose repressor protein) as a probe revealed the existence of a xylR homologue in L. brevis which is not located with the xyABT locus. (tudelft.nl)
  • A soluble 47-kDa protein derived from bacteria expressing the C. neoformans gene catalyzed conversion of UDP-glucuronic acid to UDP-xylose, as confirmed by NMR analysis. (pnas.org)
  • S. cerevisiae transformed with the synthetic gene showed sustained, non-pseudohyphal growth on D-xylose as sole carbon source, both on solid and liquid medium. (sun.ac.za)
  • Eerstens is 'n rekombinante S. cerevisiae met die xilose reduktase (XR) en xilitol dehidrogenase (XDH) gene aan nie-spesifieke mutagenese onderwerp en vir verbeterde D-xilose verbruik geselekteer. (sun.ac.za)
  • A positive result means that D-xylose is found in the blood or urine and is therefore being absorbed by the intestines. (medlineplus.gov)
  • If xylose is detected in blood and/or urine within the next few hours, it has been absorbed by the intestines. (wikipedia.org)
  • In addition, xylose-transporting properties of some homologous hexose transporters were studied. (nih.gov)
  • Furthermore, an efficient microorganism for bioethanol production has to be able to ferment xylose together with glucose since xylose represents a large fraction in the lignocellulosic biomass. (chalmers.se)
  • Fusarium oxysporum, Neurospora crassa and Paecilomyces lilacinus, and Zygomycetes including Mucor indicus and Rhizopus oryzae are also able to convert xylose to ethanol (Gong et al. (springeropen.com)
  • butyricum have been tested for their ability to ferment xylose to butanol. (semanticscholar.org)
  • The ability to ferment xylose can be a path to biofuel production that does not compete with the food supply. (tufts.edu)
  • two species known to utilize xylose. (scielo.br)
  • Many Firmicutes bacteria, including solvent-producing clostridia such as Clostridium acetobutylicum , are able to utilize xylose, an abundant carbon source in nature. (biomedcentral.com)
  • The crystallinity index of raw biomass was shown to be a major factor influencing the rate of both xylose and furfural formation. (osti.gov)
  • As a result, a positive correlation was observed between the activation energy and biomass crystallinity index for xylose formation. (osti.gov)
  • When the native xylA was expressed in E. coli and S. cerevisiae no XI activity was found, nor growth on D-xylose sustained. (sun.ac.za)
  • Toe die natuurlike xylA geen In E. coli en S. cerevisiae uitgedruk is, is geen XI-aktiwiteit of volhoubare groei op D-xilose waargeneem nie. (sun.ac.za)
  • The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. (hindawi.com)
  • Fetal and maternal blood samples and amniotic and allantoic fluids were collected for the determination of glucose and xylose concentrations. (bvsalud.org)
  • A xylose test checks the level of xylose in both blood and urine. (medlineplus.gov)
  • A xylose test involves getting samples from both blood and urine. (medlineplus.gov)
  • For the urine tests , you will need to collect all the urine you produce for five hours after you have taken the xylose solution. (medlineplus.gov)
  • If your xylose blood levels were normal, but urine levels were low, it may be a sign of kidney disease and/or malabsorption. (medlineplus.gov)
  • In pigs fed on the 100 g D-xylose/kg diet, 44.5% of the D-xylose intake appeared in the urine. (tudelft.nl)
  • Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. (hindawi.com)
  • Galactose is transformed into glucose in the liver, while xylose, which is passively absorbed [ 8 ], is partially endogenously metabolized, with the rest appearing in blood and being finally excreted in urine. (hindawi.com)
  • Xylose can be detected in urine, plasma, and serum by different reported methods [ 12 - 18 ]. (hindawi.com)
  • 13 ]. Since this method was not sensitive enough to detect the low amounts of xylose present in urine and blood after the oral ingestion of gaxilose, some modifications were introduced in the assay protocol. (hindawi.com)
  • Xylose is also found in mucopolysaccharides of connective tissue and sometimes in the urine. (hmdb.ca)
  • SSCF) of xylose and glucose has been investigated with the purpose of improving xylose conversion and ethanol yields in non-detoxified lignocellulosic hydrolyzates. (lu.se)
  • Interestingly, high yields of α-ketoglutarate (up to 0.43 g g-1) were formed during growth on xylose. (dissertations.se)
  • In 2-stage fermentations in which ATCC 8260 or NRRL 594 acted upon xylose for 12 to 20 h, followed by NRRL 527 for a total of 3 days, yields of solvent were better, 0.32 g/g xylose. (semanticscholar.org)
  • Although most efforts have heavily focused on the production of ethanol by engineered S. cerevisiae, yields and productivities of ethanol produced from xylose have remained inferior as compared with ethanol produced from glucose. (princeton.edu)
  • Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional group. (wikipedia.org)
  • D-Xylose is a five-carbon aldose (pentose, monosaccharide) that can be catabolized or metabolized into useful products by a variety of organisms. (wikipedia.org)
  • The medium is void of peptones but instead uses yeast extract as a carbon, nitrogen and vitamin source and xylose, lactose and sucrose are fermentable carbohydrates. (neogen.com)
  • a breath test for bacterial overgrowth in the intestine in which the fasting patient is administered a dose of D -xylose labeled with carbon 14 and the amount of radiolabeled carbon dioxide in the breath is measured at regular time intervals. (thefreedictionary.com)
  • Humans have enzymes called protein xylosyltransferases (XYLT1, XYLT2) which transfer xylose from UDP to a serine in the core protein of proteoglycans. (wikipedia.org)
  • the xylanolytic and cellulolytic systems are strictly coregulated via the inducer xylose ( 10 , 15 ), enzymes participating in the respective T. reesei hydrolytic systems are not. (asm.org)
  • The similar labelling patterns of amino acids (His, Ala, Ser, Val and Gly) from glucose and xylose feeding experiments suggests that PPP would be the main metabolic route in Xoo. (mdpi.com)
  • Xylose-isomerases are also commonly called fructose-isomerases due to their ability to interconvert glucose and fructose. (wikipedia.org)
  • The tertiary structure was determined for several xylose isomerases from microbes starting in the mid 1980s (Streptomyces olivochromogenes in 1988, Streptomyces violaceoniger in 1988, Streptomyces rubiginosus in 1984, Arthrobacter B3728 in 1986, Actinoplanes missouriensis in 1992, and Clostridium thermosulfurogenes in 1990). (wikipedia.org)