The thermotolerant yeast Kluyveromyces marxianus shows promise as an industrial host for the biochemical production of fuels and chemicals. Wild-type strains are known to ferment high titers of ethanol and can effectively convert a wide range of C5, C6, and C12 sugars into the volatile short-chain ester ethyl acetate. Strain engineering, however, has been limited due to a lack of advanced genome-editing tools and an incomplete understanding of ester and ethanol biosynthesis. Enabled by the design of hybrid RNA polymerase III promoters, this work adapts the CRISPR-Cas9 system from Streptococcus pyogenes for use in K. marxianus. The system was used to rapidly create functional disruptions to alcohol dehydrogenase (ADH) and alcohol-O-acetyltransferase (ATF) genes with putative function in ethyl acetate and ethanol biosynthesis. Screening of the KmATF disrupted strain revealed that Atf activity contributes to ethyl acetate biosynthesis, but the knockout reduced ethyl acetate titers by only ~15%.
Kluyveromyces marxianus is an aerobic yeast capable of respiro-fermentative metabolism that consists of simultaneously generating energy from both respiration via the TCA cycle and ethanol fermentation.[2] The balance between respiration and fermentation metabolisms is strain specific.[5] This species also ferments inulin, glucose, raffinose, sucrose and lactose into ethanol.[5][8] K. marxianus is widely used in industry because of its ability to use lactose. Two genes, LAC12 and LAC4, allow K. marxianus to absorb and use lactose as a carbon source.[5] This species is considered to be a "crabtree negative fungus", meaning it is unable to convert sugars into ethanol as effectively as crabtree positive taxa such as S. cerevisiae.[4] Studies, however, deem it to be crabtree positive which is likely due to strain differences since K. marxianus possesses the necessary genes to be crabtree positive.[5] K. marxianus is highly thermotolerant and able to withstand temperatures up to 45 °C (113 °F).[2] ...
To generate a simplified signal sequence, we substituted a part of the yGLuc hydrophobic core with repeats of a single amino acid. The VLFALICI sequence was initially substituted to contain an eight residue repeat of a single amino acid (Figure 3). L8, M8, W8, and F8 increased secreted protein activity but repeats containing other residues (I, T, S, Q, Y, A, V, and C) did not. This result indicated that a complex amino acid sequence such as VLFALICI can be substituted with a repeat of select, single amino acids. Furthermore, although eight residue repeats of the residues I, T, S, Q, Y, A, V, and C, appeared not to be suitable, or too weak for a hydrophobic core; in fact, a hydrophobic core consisting of I12 and I13 was able to function as a signal sequence (Figure 5a). Therefore, the hydrophobic core in a signal sequence can be determined by the number of hydrophobic amino acids without including charged amino acids such as E, D, R, and K. Moreover, the efficiency of secretory production can be ...
Wang, R., Wang, D., Gao, X. and Hong, J. (2014), Direct fermentation of raw starch using a Kluyveromyces marxianus strain that expresses glucoamylase and Alpha-amylase to produce ethanol. Biotechnol Progress, 30: 338-347. doi: 10.1002/btpr.1877 ...
TY - JOUR. T1 - Identification of the first fungal NADP-GAPDH from Kluyveromyces lactis. AU - Verho, Ritva. AU - Richard, Peter. AU - Jonson, Per Harald. AU - Sundqvist, Lena. AU - Londesborough, John. AU - Penttilä, Merja. PY - 2002/11/19. Y1 - 2002/11/19. N2 - Deletion of the phosphoglucose isomerase gene, PGI1, in Saccharomyces cerevisiae leads to a phenotype for which glucose is toxic. This is related to overproduction of NADPH through the oxidative part of the pentose phosphate pathway and the incompetence of S. cerevisiae to deal with this overproduction. A similar deletion (rag2) in Kluyveromyces lactis does not lead to such a phenotype. We transformed a genomic library of K. lactis in a yeast vector to a S. cerevisiae strain with a pgi1 deletion and screened for growth on glucose. We found a gene (GDP1) which encodes a phosphorylating glyceraldehyde-3-phosphate dehydrogenase, NADP-GAPDH (EC 1.2.1.13), that accepts both NADP and NAD. This is the first report of a eukaryotic, nonplant, ...
Under certain conditions, ROS generated from cell metabolism causes more cell damages, and ROS generally includes super oxide, peroxide, and hydroxyl radical et al. [32]. In order to prevent from ROS damages, microorganisms build a perfect defense system, which involves some essential oxidoreductases and compounds, such as peroxiredoxins (Prxs), thioredoxin (TRX) and its reductase (TrxR), glutathione and its reductase (GLR) and peroxidase (GPX), catalase (CTT1), and superoxide dismutase (SOD) (Fig. 7a). These oxidoreductases might be also related to the tolerance to some specific inhibitors [32, 33]. Actually, the peroxiredoxin, encoded by KmTPX1, has been proved to contribute to an obvious enhancement of tolerance to both oxidative stress and lignocellulose-derived inhibitors [29]. Therefore, to further explore the potential functions of oxidoreductases on cells survival under tough conditions, the thioredoxin system from K. marxianus, composed of thioredoxin (KmTrx) and its reductase (KmTrxR), ...
Aggregation of the yeast Kluyveromyces bulgaricus is mediated by the galactose-specific lectin KbCWL1. This lectin contains hydrophobic amino acids and its activity is calcium dependent. A specific fluorescent probe, 1-anilinonaphthalene-8-sulfonic acid in the free acid form (ANS; Sigma Chemical Co., St. Louis, Missouri), was used to study the hydrophobic areas on the cellular surface of K. bulgaricus. Changes in surface hydrophobicity during the growth and aggregation of yeast cells were studied. Surface hydrophobicity increased during growth and depended on the amount of yeast cells in the culture medium. During growth, the size of the hydrophobic areas on the cell surface was measured using ANS and was found to increase with the percentage of flocculating yeasts. Our results strongly suggest that the hydrophobic areas of the cell walls of yeast cells are involved in the aggregation of K. bulgaricus.
Eukaryotic cells have evolved signalling pathways that allow adaptation to harmful conditions that disrupt endoplasmic reticulum (ER) homeostasis. When the function of the ER is compromised in a condition known as ER stress, the cell triggers the unfolded protein response (UPR) in order to restore ER homeostasis. Accumulation of misfolded proteins due to stress conditions activates the UPR pathway. In mammalian cells, the UPR is composed of three branches, each containing an ER sensor (PERK, ATF6 and IRE1). However, in yeast species, the only sensor present is the inositol-requiring enzyme Ire1. To cope with unfolded protein accumulation, Ire1 triggers either a transcriptional response mediated by a transcriptional factor that belongs to the bZIP transcription factor family or an mRNA degradation process. In this review, we address the current knowledge of the UPR pathway in several yeast species: Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida glabrata, Cryptococcus neoformans, and Candida
Marwaha, S.S.; Kennedy, J.F.; Sehgal, V.K., 1988: Simulation of process conditions of continuous ethanol fermentation of whey permeate using alginate entrapped Kluyveromyces marxianus NCYC 179 cells in a packed-bed reactor system
Kluyveromyces bulgaricus yeast lectins. Isolation of two galactose-specific lectin forms from the yeast cell wall.: Incubation of galactose treated Kluyveromyce
We present a method for estimating and providing a confidence interval for the number of DNA replication origins in the genome of the yeast Kluyveromyces lactis. The method requires an initial set of verified sites from which a position specific frequency matrix (PSFM) can be constructed. We further assume that we have access to a sparingly used experimental procedure which can verify the functionality of a few, but not all, computationally predicted sites. While our motivation comes from estimating the number of autonomously replicating sequences (ARSs), our method can also be applied to estimating the genome-wide number of functional transcription factor binding sites, where functionality is determined by experimental verification of the transcription factor binding event using, for example, ChIP data. The reliability of our method is demonstrated by correctly predicting the known number of Saccharomyces cerevisiae ARSs as well as the number of S. cerevisiae probes that bind to the ...
The vector pKLCF-n permits secreted expression of a recombinant protein having a chitin-binding domain (CBD) affinity tag fused to its amino-terminus in the yeast Kluyveromyces lactis . It is compatible with the K
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The yeast Saccharomyces cerevisiaeis probably the most thoroughly understood amongst eukaryotic organisms and an excellent model for the study of eukaryotic cells in general; indeed, the term...
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Mitogen-activated protein kinase involved in a signal transduction pathway that is activated by changes in the osmolarity of the extracellular environment. Controls osmotic regulation of transcription of target genes (By similarity).
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 ...
The citrate cycle (TCA cycle, Krebs cycle) is an important aerobic pathway for the final steps of the oxidation of carbohydrates and fatty acids. The cycle starts with acetyl-CoA, the activated form of acetate, derived from glycolysis and pyruvate oxidation for carbohydrates and from beta oxidation of fatty acids. The two-carbon acetyl group in acetyl-CoA is transferred to the four-carbon compound of oxaloacetate to form the six-carbon compound of citrate. In a series of reactions two carbons in citrate are oxidized to CO2 and the reaction pathway supplies NADH for use in the oxidative phosphorylation and other metabolic processes. The pathway also supplies important precursor metabolites including 2-oxoglutarate. At the end of the cycle the remaining four-carbon part is transformed back to oxaloacetate. According to the genome sequence data, many organisms seem to lack genes for the full cycle [MD:M00009], but contain genes for specific segments [MD:M00010 M00011 ...
Next-day shipping cDNA ORF clones derived from KLLA0_C11385g uncharacterized protein available at GenScript, starting from $99.00.
ID F2Z6F9_KLULA Unreviewed; 108 AA. AC F2Z6F9; DT 31-MAY-2011, integrated into UniProtKB/TrEMBL. DT 31-MAY-2011, sequence version 1. DT 25-OCT-2017, entry version 37. DE SubName: Full=KLLA0C03091p {ECO:0000313,EMBL:CAH01186.1}; GN ORFNames=KLLA0_C03091g {ECO:0000313,EMBL:CAH01186.1}; OS Kluyveromyces lactis (strain ATCC 8585 / CBS 2359 / DSM 70799 / NBRC OS 1267 / NRRL Y-1140 / WM37) (Yeast) (Candida sphaerica). OC Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; OC Saccharomycetes; Saccharomycetales; Saccharomycetaceae; Kluyveromyces. OX NCBI_TaxID=284590 {ECO:0000313,Proteomes:UP000000598}; RN [1] {ECO:0000313,EMBL:CAH01186.1, ECO:0000313,Proteomes:UP000000598} RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 / NRRL Y-1140 / RC WM37 {ECO:0000313,Proteomes:UP000000598}; RX PubMed=15229592; DOI=10.1038/nature02579; RG Genolevures; RA Dujon B., Sherman D., Fischer G., Durrens P., Casaregola S., RA Lafontaine I., de Montigny J., Marck ...
Intergeneric transfer of deoxyribonucleic acid killer plasmids, pGKl1 and pGKl2, from Kluyveromyces lactis into Saccharomyces cerevisiae by cell ...
The endoplasmic reticulum (ER)-mitochondrial encounter structure (ERMES) physically links the membranes of the ER and mitochondria in yeast. Although the ER and mitochondria cooperate to synthesize glycerophospholipids, whether ERMES directly facilitates the lipid exchange between the two organelles remains controversial. Here, we compared the x-ray structures of an ERMES subunit Mdm12 from Kluyveromyces lactis with that of Mdm12 from Saccharomyces cerevisiae and found that both Mdm12 proteins possess a hydrophobic pocket for phospholipid binding. However in vitro lipid transfer assays showed that Mdm12 alone or an Mmm1 (another ERMES subunit) fusion protein exhibited only a weak lipid transfer activity between liposomes. In contrast, Mdm12 in a complex with Mmm1 mediated efficient lipid transfer between liposomes. Mutations in Mmm1 or Mdm12 impaired the lipid transfer activities of the Mdm12-Mmm1 complex and furthermore caused defective phosphatidylserine transport from the ER to mitochondrial ...
Molecular cloning of the plasma membrane H(+)-ATPase from Kluyveromyces lactis: a single nucleotide substitution in the gene confers ethidium bromide resistance
[169 Pages Report] Specialty Yeast Market report categorizes the global market by Species (Saccharomyces Cerevisiae, Pichia Pastoris, Kluyveromyces), Application, Type (Yeast Extracts, Yeast Autolysates, Yeast Beta-glucan, and Other Yeast Derivatives), and by Region
Inulin is linear oligosaccharides [1]. Although inulin can be hydrolyzed to monosaccharides non-enzymatically by acid treatment, inhibitory by-products produced that complicate downstream biological process. Therefore, it is pivotal to establish a cost-effective inulinase (EC 3.2.1.7) production. In this study, we isolated the DNA sequence encoding the mature peptide sequence of the exo-inulinase gene from Kluyveromyces marxianus CBS 6556 and expressed in Pichia pastoris X-33. The purified recombinant enzyme (reINU) gave a specific activity of 13100 U•mg−1, which was about 100-fold higher that reported for the wild type protein isolated from K. marxianus CBS6556 [2, 3]. Ferguson plot analysis showed that secretion expressed reINU was a 169 kDa dimer. Detailed analytical assays showed that the optimal temperature and pH for reINU were 60 oC and pH 4.0, respectively. It was found that hydrolysis activity was about 20% higher in the presence of Mn2+. reINU was stable for over 3 days at room ...
SUMMARY: Long-chain fatty acid compositions were determined for strains of seven species of Candida and their counterparts within the perfect genera: Candida shehatae and Pichia stipitis, Candida kefyr and Kluyveromyces marxianus, Candida lipolytica and Yarrowia lipolytica, Candida pelliculosa and Hansenula anomala, Candida pseudotropicalis and Kluyveromyces fragilis, Candida utilis and Hansenula jadinii, Candida parapsilosis and Lodderomyces elongisporus, Candida shehatae and Pichia stipitis. Close correlations were found between the fatty acid compositions of these pairs of strains, indicating that the analysis of long-chain fatty acids may be useful for studying the relationships between the perfect and imperfect states of the genus Candida.
The whey is a by-product obtained during the manufacture of cheese. It includes three types of whey; sweet (SW), acid (AW) and curd (CW). These residues are rich in lactose and proteins. Practically, there are no studies on the use of the three types of whey, as a substrate of micro-organisms for the production of phenylethyl alcohol (PEA). We assessed the production of PEA by Kluyveromyces marxianus using SW, AW and CW as substrate. Whey pH was adjusted to 4.8, pasteurized at 63C/30min and inoculated with K. marxianus (1×106CFUmL?1). The inoculated whey was embedded in agitation (180rpm) at 30C for 96h. The identification and quantification of PEA was performed by gas chromatography. In addition, it was determined the percentage of (???) lactose by molecular structure with nuclear magnetic resonance. K. marxianus was capable of producing PEA in the three types of whey (SW, AW and CV) in maximum concentrations of 0.96, 0.70, and 0.47g L?1, respectively. For SW (maximum concentration of PEA), it ...
pH increasing problem of yeast fermentation (under aerobic condition) - posted in Microbiology: Dear all, Recently I did consuming experiments with two monosaccharides (glucose and galactose) by Kluyveromyces marxianus (yeast) in the fermentor. The initial pH of medium is 7.0. I think it is normal that the pH dropped down to 6.5 after overnight incubation while stirring but without ventilation.But I also found that when the reaction is stirring with ventilation, the pH increases immediatel...
Most pomegranate (Punica granatum Linn., Punicaceae) fruit parts are known to possess enormous antioxidant activity. The present study used Kluyveromyces marxianus NRRL Y-8281, as yeast candidate to enhance the antioxidant activities of pomegranate peel by modulating polyphenolic substances during solid state fermentation, in an attempt to examine the protective effects of either methanolic extract of unfermented (UFPP) or fermented (FPP) pomegranate peels on adriamycin-induced myocardial and renal toxicities in rats. Both extracts were found to contain a large amount of polyphenols and exhibit enormous antioxidant activity. UFPP and FPP extracts showed 92% and 93% antioxidant activity in DPPH model system respectively, while the phenolic content recorded 160 and 211 mg gallic acid/ g dry peel for UFPP and FPP respectively at concentration of 125 µg /ml. Administration of adriamycin (10 mg/Kg body weight /day, i.p. for 3 days) caused significant rise in the levels of diagnostic markers [serum creatine
To delete SGO1, primers O361 and O362 were used to PCR amplify the Kluyveromyces lactis TRP1 selective marker from plasmid pBS1479 (47), and the PCR product was transformed into yeast cells for tryptophan prototroph selection.. To tag endogenous Pds1p with 13×Myc, O323 and O324 were used to PCR amplify pFA6a-13Myc-TRP1 for yeast integrative transformation. Integration was verified with PDS1-specific primers O325 and O326 and TRP1-specific primers O375 and O376. Mcd1p-13Myc was created in a scheme identical to that used for Pds1p-13Myc, except for the use of MCD1-specific primers OJL21, OJL22 (for integration), and OJL23 (for verification). To introduce a carboxyl-terminal six-hemagglutinin (6×HA) tag into Sgo1p, yeast strain A10652 (22) was used for a genomic PCR (primers O363 and O364) that amplified the 6×HA-TRP1 fragment flanked by SGO1 sequences. The resultant PCR product was transformed into yMK1243 and yJL145 to knock in the HA tag and the TRP1 marker, creating yJL343 and yJL344, ...
A method for immobilization of ß-galactosidase from Kluyveromyces lactis on an adsorptive membrane for the continuous synthesis of galacto-oligosaccharides from lactose was carried out. The immobilization was performed at ...
In this study, in vitro antioxidant and antimicrobial activities of the E. spectabilis Bieb., which is consumed as a vegetable among people, was investigated and Kluyveromyces lactiss antioxidant activies in anaerobic cultural environment is researched. This purpose; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, flavonoid, resveratrol, sugar contents, lipid peroxidation (LPO) levels, fatty acid level, lipophilic vitamin values, protein and glutathione amounts were measured. In the FeCl group in which FeCl2+ H2O2 is applied, when compared with LPO level control group (K), it was observed that it increase in high amount (p,0.05). LPO level decreases in certain proportions in treatment groups. It is suggested that the lowering effect of the LPO of E. spectabilis extracts are arise from phytochemical like flavonoids that it includes. As a result of the antibacterial activity studies, it was observed that E. spectabilis have different proportional antimicrobial activities against ...
Krick, R.; Busse, R. A.; Scacioc, A.; Stephan, M.; Janshoff, A.; Thumm, M.; Kühnel, K.: Structural and functional characterization of the two phosphoinositide binding sites of PROPPINs. Proceedings of the National Academy of Sciences of the United States of America 109 (30), S. E2042 - E2049 (2012 ...
Thermotolerant yeasts, which are expected to be applicable for high-temperature fermentation as an economical process, were isolated from four provinces in Laos. Of these yeasts, five isolates exhibited stronger fermentation abilities in a 16% sugars-containing medium of glucose, sucrose, sugarcane or molasses at 40°C than that of Kluyveromyces marxianus DMKU 3-1042, one of the most thermotolerant and efficient yeasts isolated previously in Thailand. One of the five strains, BUNL-17, exhibited the highest ethanol fermentation performance at 45°C. Yeast identification was achieved by whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) analysis as well as by nucleotide sequencing of the D1/D2 domain of the large subunit rRNA gene, revealing that the isolated strains can be categorized into Pichia kudriavzevii, Cyberlindnera rhodanensis and K. marxianus and that all of the five strains are K. marxianus. The results of this study showed that the ...
The soybean aphid, Aphis glycines (Hemiptera: Aphididae), is a consistent pest of soybean in Iowa. Current management is heavily reliant on the use of insecticides, which can be expensive and time consuming to apply. Soybean varieties resistant to the aphid are available. These varieties primarily include one resistance gene (Rag1) for soybean aphid control. Varieties incorporating two genes (Rag1 + Rag2) have recently become available. We sought to compare soybean lines susceptible to the soybean aphid with lines carrying a single resistance gene (Rag1 or Rag2) and a line carrying two resistance genes (Rag1 + Rag2). We evaluated the lines based on aphid control and yield protection.
To determine the role of NIPPV in CF patients awaiting lung transplantation. This paper describes the tadalafil 20mg rationale, study design and procedures of the National Eye Survey of Trinidad and Tobago (NESTT). MCRT (YPFPFRTic-NH(2)) is a chimeric opioid peptide based on morphiceptin and PFRTic-NH(2).. Concentrations of highly sensitive cardiac troponin-I predict poor cardiovascular outcomes and adverse remodeling in chronic heart failure. The primary structure of the 3-phosphoglycerate viagra cialis online pharmacy kinase (PGK) gene from Kluyveromyces lactis. Survival information on all patients tadalafil side effects was obtained by use of combined registers. Interleukin-1 regulates hematopoietic progenitor and stem cells in the midgestation mouse fetal liver.. Animal models of peritoneal dialysis: relevance, difficulties, and future Results in this study will be helpful in understanding the phytoplankton diversity effects on ecosystem functioning and how these viagra or cialis effects are ...
Our knowledge of yeast genomes remains largely dominated by the extensive studies on Saccharomyces cerevisiae and the consequences of its ancestral duplication, leaving the evolution of the entire class of hemiascomycetes only partly explored. We concentrate here on five species of Saccharomycetaceae, a large subdivision of hemiascomycetes, that we call "protoploid" because they diverged from the S. cerevisiae lineage prior to its genome duplication. We determined the complete genome sequences of three of these species: Kluyveromyces (Lachancea) thermotolerans and Saccharomyces (Lachancea) kluyveri (two members of the newly described Lachancea clade), and Zygosaccharomyces rouxii. We included in our comparisons the previously available sequences of Kluyveromyces lactis and Ashbya (Eremothecium) gossypii. Despite their broad evolutionary range and significant individual variations in each lineage, the five protoploid Saccharomycetaceae share a core repertoire of approximately 3300 protein ...
Genome-wide analysis of chitinase genes in the Hypocrea jecorina (anamorph: Trichoderma reesei) genome database revealed the presence of 18 ORFs encoding putative chitinases, all of them belonging to glycoside hydrolase family 18. Eleven of these encode yet undescribed chitinases. A systematic nomenclature for the H. jecorina chitinases is proposed, which designates the chitinases corresponding to their glycoside hydrolase family and numbers the isoenzymes according to their pI from Chi18-1 to Chi18-18. Phylogenetic analysis of H. jecorina chitinases, and those from other filamentous fungi, including hypothetical proteins of annotated fungal genome databases, showed that the fungal chitinases can be divided into three groups: groups A and B (corresponding to class V and III chitinases, respectively) also contained the so Trichoderma chitinases identified to date, whereas a novel group C comprises high molecular weight chitinases that have a domain structure similar to Kluyveromyces lactis killer toxins.
Inappropriate activation of a single enzyme, telomerase, is associated with the uncontrolled proliferation of cells seen in as many as 90 percent of all human c...
Galactosyl-oligosaccharides (GOS) are non-digestible oligosaccharides which are qualified as functional foods. GOS are enzymatically synthesized from lactose by transgalactosylation catalyzed by the enzyme β-galactosidase. In this study, a method for immobilization of β-galactosidase from Kluyveromyces lactis on a chromatography membrane was developed. The immobilization was performed at 4, 15 and 40°C. A strong basic anion exchange membrane was investigated. In static experiments the highest enzyme activity was measured at an immobilization procedure temperature of 15°C. The immobilization on the chromatography membranes was found to be very rapid likely due to ionic adsorption. The synthesis of GOS was carried out in a Continuous Membrane Chromatography Reactor System (CMCRS) at 40°C and pH 7.0 using 20 wt% initial lactose concentration. The chromatography membranes proved to be a good support for the continuous process at high convective flow rates in the enzyme reactor system. Up to 82 ...
The ability to utilize nitrate as a sole source of nitrogen is an important taxonomic indicator of some species. Previous research by Hipkin has grouped yeasts on the basis of nitrate utilization, with some species being able to assimilate nitrate ( Brettanomyces, Candida, Hansenula, Pachysolen, and Rhodotorula ) while others are not ( Kluyveromyces, Pichia, Saccharomyces and Schizosaccharomyces ). (8) Nitrate assimilation is defined simply as the utilization of a nitrogen source by a microorganism in the presence of oxygen. A positive reaction is indicated by the presence of growth or the use of a pH indicator in the medium. The indicator method is a modification of the Wickerham method that was devised by Adams and Cooper. (7) The use of this method is easier to read than conventional techniques, yet it is equally as reliable. (7) Additionally, this method is not affected by carry-over of the inoculum. Hardy Diagnostics Modified Nitrate Assimilation Agar contains a yeast carbon base composed ...
Rag6 and Rag3c were delimited to a 49-kb interval on chromosome 8 and a 150-kb interval on chromosome 16, respectively. Structural variants in the exons of candidate genes were identified.. The soybean aphid, an invasive species, has significantly threatened soybean production in North America since 2000. Host-plant resistance is known as an ideal management strategy for aphids. Two novel aphid-resistance loci, Rag6 and Rag3c, from Glycine soja 85-32, were previously detected in a 10.5-cM interval on chromosome 8 and a 7.5-cM interval on chromosome 16, respectively. Defining the exact genomic position of these two genes is critical for improving the effectiveness of marker-assisted selection for aphid resistance and for identification of the functional genes. To pinpoint the locations of Rag6 and Rag3c, four populations segregating for Rag6 and Rag3c were used to fine map these two genes. The availability of the Illumina Infinium SoySNP50K/8K iSelect BeadChip, combined with single-nucleotide ...
Lactococcus lactis is a Gram-positive bacterium used extensively in the production of buttermilk and cheese, but has also become famous as the first genetically modified organism to be used alive for the treatment of human disease. L. lactis cells are cocci that group in pairs and short chains, and, depending on growth conditions, appear ovoid with a typical length of 0.5 - 1.5 µm. L. lactis does not produce spores (nonsporulating) and are not motile (nonmotile). They have a homofermentative metabolism, meaning they produce lactic acid from sugars. Theyve aso been reported to produce exclusive L-(+)-lactic acid. However, reported D-(−)-lactic acid can be produced when cultured at low pH. The capability to produce lactic acid is one of the reasons why L. lactis is one of the most important microorganisms in the dairy industry. Based on its history in food fermentation, L. lactis has generally recognized as safe (GRAS) status with few case reports of being an opportunistic pathogen. L. lactis ...
Problem statement: This work reports the Penicillium citrinum ESS strain as a new source of inulinase (2,1-β-D fructanhydrolase, E.C. 3.2.1.7). Approach: The enzyme was produced in both, Solid-State (SSC) and Submerged Culture (SmC) using a basal medium added either with inulin or sucrose (5 gL-1). Results: The culture grew faster in SmC than in SSC with both carbon sources; however, yields of inulinase activity per gram of biomass were higher in SSC (1,658,237.28 for inulin and 66598.96 for sucrose) than in SmC (441.05 for inulin and 183.91 for sucrose). Conclusion: The highest inulinase production was obtained by SSC, either with inulin or sucrose, reaching values of 6650 and 2970 U/L respectively. In contrast, in SmC were obtained higher levels of inulinase activity (2241 U/L) with sucrose as carbon source (24 h), while with inulin, the enzyme production was negatively affected and retarded.
Hi, I am looking for a library of K.lactis (or a species closely related to S.cerevisiae) DNA in a Saccharomyces vector. Please e-mail me if you have such a library and are willing to spare some! Thanks very much, John Puziss ...
The level of microbiological contamination with yeasts and moulds in samples of goat milk collected in spring, summer and autumn season was evaluated. Yeasts are present in a larger number in the analyzed goat milk with values between 1.9-3.42 log CFU/ml, contrast to molds that had a range of mean values between 1.47-3.02 log CFU/ml. Of the milk samples were isolated mould strains belonged to genera: Cladosporium sp., Fusarium sp., Penicillium sp. and yeasts genera as Kluyveromyces sp., Rhodotorula sp., Cryptococcus sp. The outcome of this study indicate mycotic contamination of goat milk that can pose serious health risk to consumers ...
The level of microbiological contamination with yeasts and moulds in samples of goat milk collected in spring, summer and autumn season was evaluated. Yeasts are present in a larger number in the analyzed goat milk with values between 1.9-3.42 log CFU/ml, contrast to molds that had a range of mean values between 1.47-3.02 log CFU/ml. Of the milk samples were isolated mould strains belonged to genera: Cladosporium sp., Fusarium sp., Penicillium sp. and yeasts genera as Kluyveromyces sp., Rhodotorula sp., Cryptococcus sp. The outcome of this study indicate mycotic contamination of goat milk that can pose serious health risk to consumers ...