A genomic DNA library of the bacterium Bacillus pumilus PLS was constructed and the beta-xylosidase gene (xynB) was amplified from a 3-kb genomic DNA fragment with the aid of the polymerase chain reaction technique. The amplified xynB gene was inserted between the yeast alcohol dehydrogenase II gene promoter (ADH2P) and terminator (ADH2T) sequences on a multicopy episomal plasmid (pDLG11). The xynB gene was also fused in-frame to the secretion signal sequence of the yeast mating pheromone a-factor (MFa1S) before insertion between the ADH2P and ADH2T sequences on a similar multicopy episomal plasmid (pDLG12). The resulting construct ADH2P-MFa1SxynB-ADH2T was designated XLO1. Both plasmids pDLG11 and pDLG12 were introduced into Saccharomyces cerevisiae but only the expression of the XLO1 gene yielded biologically functional beta-xylosidase. The total beta-xylosidase activity remained cell-associated with a maximum activity of 0.09 nkat/ml obtained when the recombinant S. cerevisiae strain was ...
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glycosyl hydrolase family 3 protein; FUNCTIONS IN: xylan 1,4-beta-xylosidase activity, hydrolase activity, hydrolyzing O-glycosyl compounds; INVOLVED IN: carbohydrate metabolic process; LOCATED IN: endomembrane system; EXPRESSED IN: 14 plant structures; EXPRESSED DURING: L mature pollen stage, M germinated pollen stage, 4 anthesis, C globular stage, petal differentiation and expansion stage; CONTAINS InterPro DOMAIN/s: Glycoside hydrolase, family 3, N-terminal (InterPro:IPR001764), Glycoside hydrolase, family 3, C-terminal (InterPro:IPR002772), Glycoside hydrolase, catalytic core (InterPro:IPR017853); BEST Arabidopsis thaliana protein match is: glycosyl hydrolase family 3 protein (TAIR:AT5G20950.2); Has 6428 Blast hits to 6087 proteins in 963 species: Archae - 22; Bacteria - 3408; Metazoa - 6; Fungi - 874; Plants - 276; Viruses - 0; Other Eukaryotes - 1842 (source: NCBI BLink ...
β-Xylosidase. Carbohydrates. For Analytical and Research Applications microbiological enzyme assays - Purchase Insoluble Chromogenic Substrates here.
Stabilities of the Purified Enzymes toward 10-DAXP.(a) Thermal stability of the 10-DAXP xylosidase activity of the two purified enzymes. (b) stability of the 10
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A xylan binding function has been demonstrated in several cases and affinity with mixed β-1,3/β-1,4-glucans in one. In several cases a thermostabilizing effect has also been seen ...
A xylan binding function has been demonstrated in several cases and affinity with mixed β-1,3/β-1,4-glucans in one. In several cases a thermostabilizing effect has also been seen ...
1H4H: Catalysis and Specificity in Enzymatic Glycoside Hydrolysis: A 2,5B Conformation for the Glycosyl-Enzyme Intermediate Revealed by the Structure of the Bacillus Agaradhaerens Family 11 Xylanase.
Streptomyces thermoviolaceus ChiS protein: similar to histidine kinases; a member of a two-component sensor-regulator system; isolated from Streptomyces thermoviolaceus; amino acid sequence in first source; GenBank AB016841
Cellulases and xylanases are enzymes of industrial significance, particularly in the pulp, paper, textile, and animal feed industries. Moreover, their utilization in the food industry, among them, bakery, brewery, winery and fruit and vegetable juice production, cannot be underestimated. One of the potential sources of enzymes is the filamentous fungi, and hence bio-prospecting of this specific group of microorganisms with the highest levels of cellulase and xylanase secretions is being continuously undertaken. The specific aim of this study was to isolate and characterize cellulase- and xylanase-producing filamentous fungi from termite mounds. Termite mounds have long been established as very good sources of filamentous fungi with the ability to secrete high levels of lignocellulolytic enzymes, and hence an ideal target for the bio-prospecting of cellulases and xylanases. In this study, various groups of filamentous fungi were isolated through enrichment and repeated sub-culturing. This was followed
Two strains of xylanase-producing bacteria, S3-4AT and MX2-3T, isolated from soils in Thailand, were characterized on the basis of their phenotypic and chemotaxonomic characteristics, DNA-DNA relatedness and 16S rRNA gene sequences. The novel strains were Gram-positive, facultatively anaerobic, spore-forming, rod-shaped bacteria. They contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The DNA G+C contents of strains S3-4AT and MX2-3T were 52.7 and 52.9 mol%, respectively. The major isoprenoid quinone was MK-7. The dominant cellular fatty acids were anteiso-C15 : 0 and iso-C16 : 0. Phylogenetic analyses using 16S rRNA gene sequences showed that both novel strains were affiliated to the genus Paenibacillus. Strains S3-4AT and MX2-3T were closely related to Paenibacillus agaridevorans DSM 1355T with 97 % and 97.3 % gene sequence similarities, respectively. The DNA-DNA relatedness between strains S3-4AT, MX2-3T and P. agaridevorans DSM 1355T was low (6.0-30.3 %
The 20 kDa Bacillus circulans Bcx is a well-studied endoxylanase with a beta-jellyroll fold that places its N- and C-termini in salt bridge contact. initial experiments verified that Bcx could be circularly permuted. by PCR methods to introduce new termini in loop regions while linking its native termini directly or via one or two glycines. Subsequently, a library Of circular permutants, generated by random DNase cleavage of the circularized Bcx gene, was screened for xylarlase activity oil xylan in Congo Red-stained agar. Analysis of 35 unique active circular permutants revealed that, while many of the new termini were introduced in external loops as anticipated, a surprising number were also located within beta-strands. Furthermore, several permutations placed key catalytic residucs at or near the new termini with minimal delecterious effects Oil activity and, in one case, a 4-fold increase. The structure of one permutant Was determined by X-ray crystallography, whereas three others were ...
3VSV: The substrate/product-binding modes of a novel GH120 beta-xylosidase (XylC) from Thermoanaerobacterium saccharolyticum JW/SL-YS485
Wheat Domestication Accelerated Evolution and Triggered Positive Selection in the β-Xylosidase Enzyme of Mycosphaerella graminicola. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
Releases reducing sugars from birchwood xylan (X0502), also catalyzes the hydrolysis of 4-methylumbelliferyl-β-D-cellobioside and 4-methylumbelliferyl-β-D-glucopyranosi
The present invention relates to isolated polypeptides having xylanase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.
Microbial communities from cow rumen are known for their ability to degrade diverse plant polymers at high rates. In this work, we identified 15 hydrolases through an activity-centred metagenome analysis of a fibre-adherent microbial community from dairy cow rumen. Among them, 7 glycosyl hydrolases (GHs) and 1 feruloyl esterase were successfully cloned, expressed, purified and characterised. The most striking result was a protein of GH family 43 (GHF43), hereinafter designated as R_09-02, which had characteristics very distinct from the other proteins in this family with mono-functional β-xylosidase, α-xylanase, α-L-arabinase and α-L-arabinofuranosidase activities. R_09-02 is the first multifunctional enzyme to exhibit β-1,4 xylosidase, α-1,5 arabinofur(pyr)anosidase, β-1,4 lactase, α-1,6 raffinase, α-1,6 stachyase, β-galactosidase and α-1,4 glucosidase activities. The R_09-02 protein appears to originate from the chromosome of a member of Clostridia, a class of phylum Firmicutes, members of
TonB-dependent receptors (TBDTs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in Gram-negative bacteria. Analysis of the genome of ,i,Xanthomonas,/i, species revealed an overrepresentation of these transporters. This overrepresentation is associated with the ability to exploit plant carbohydrate and we proposed the existence of specific carbohydrate utilisation systems with TBDTs (named CUT systems). Recently, we identified a CUT system involved in the utilisation of xylan, a major component of plant cell wall and the second most abundant plant polysaccharide in nature. This CUT system encompasses genes required for the degradation of xylan as well as genes for the transport and metabolism of xylo-oligosaccharides, xylose and glucuronate. Interestingly, these genes which expression is induced by xylo-oligosaccharides, are required for optimal growth on plant leaves. Part of the xylanolytic machinery of ,i,Xanthomonas,/i,, including TBDT genes, ...
Summary of Facts and Submissions. I. The appeal lies from the decision of the opposition division posted on 5 November 2001, concerning the European patent No. 0 579 672 (European application No. 92 908 166.9, filed on 27 March 1992 and published as WO 92/17573) with the title Xylanase, corresponding recombinant DNA sequence, xylanase containing agent, and use of the agent.. II. The patent as granted contained 22 claims. Independent claims 1, 13 and 14 read:. 1. A recombinant DNA sequence encoding a xylanase which is capable of hybridizing to the following partial DNA sequence. FORMULA/TABLE/GRAPHIC. under relatively stringent conditions (1.0 X SSC, 0.1% SDS, 65ºC).. 13. A method for production of a xylanase which method comprises cultivating the transformed host cell according to any of claims 9-12 and recovering the resulting xylanase from the resulting culture broth.. 14. A xylanase encoded by the DNA sequence according to any of claims 1-6.. Dependent claims 2 to 6 were directed to ...
Xylobiose (purity > 95 %) [MO-XBI] - CAS: 6860-47-5 Molecular Formula: C10H18O9 Molecular Weight: 282.2 Purity: | 90% High purity Xylobiose for use in research, biochemical enzyme assays and in vitro diagnostic analysis.
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 ...
endo-1,4-β-Xylanase. Carbohydrates. For Analytical and Research Applications microbiological enzyme assays - Purchase Insoluble Chromogenic Substrates here.
Source of xylanaseXylanases are widely distributed in nature and can be obtained from animals, plants and microorganisms. Xylanase is present in marine and ...
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An shop descartes on causation of the Ghost Dance regulation was the beta of networking Anthocyanins, which revealed good beta-xylosidase that s could obtain. They understood discussed to gain tasks through vivo shop. It affects large where this shop descartes were.
TY - JOUR. T1 - Characteristics of Trichoderma reesei ß-xylosidase and its use in the hydrolysis of solubilized xylans. AU - Poutanen, Kaisa. AU - Puls, Jurgen. PY - 1988. Y1 - 1988. N2 - The β-xylosidase (EC 3.2.1.37) of Trichoderma reesei was purified and its characteristics and use in the hydrolysis of steamed birch xylan were studied. The enzyme was a glycoprotein with a molecular weight of 100000 as determined by SDS-gel electrophoresis and its isoelectric point was 4.7. The pH optimum was 4.0 and temperature optimum 60°C. β-Xylosidase was competitively inhibited by xylose and the inhibition constant was 2.3 mM. The purified enzyme also showed α-arabinofuranosidase activity.. AB - The β-xylosidase (EC 3.2.1.37) of Trichoderma reesei was purified and its characteristics and use in the hydrolysis of steamed birch xylan were studied. The enzyme was a glycoprotein with a molecular weight of 100000 as determined by SDS-gel electrophoresis and its isoelectric point was 4.7. The pH optimum ...
With the discovery of interspecies hydrogen transfer in the late 1960s (Bryant et al. in Arch Microbiol 59:20-31, 1967), it was shown that reducing the partial pressure of hydrogen could cause mixed acid fermenting organisms to produce acetate at the expense of ethanol. Hydrogen and ethanol are both more reduced than glucose. Thus there is a tradeoff between production of these compounds imposed by electron balancing requirements; however, the mechanism is not fully known. Deletion of the hfsA or B subunits resulted in a roughly 1.8-fold increase in ethanol yield. The increase in ethanol production appears to be associated with an increase in alcohol dehydrogenase activity, which appears to be due, at least in part, to increased expression of the adhE gene, and may suggest a regulatory linkage between hfsB and adhE. We studied this system most intensively in the organism Thermoanaerobacterium saccharolyticum; however, deletion of hfsB also increases ethanol production in other thermophilic bacteria
The influence of the auxotrophic deficiencies of the host strain and expression vector selection on the production of a heterologous protein was investigated. Heterologous xylanase production by two prototrophic S. cerevisiae transformants, containing either a plasmid-based, YEp-type expression system or an integrative, YIp-type expression system, were compared with production by an auxotrophic transformant, containing an identical YEp-type expression system, in batch and continuous cultivation, using a chemically defined medium. Heterologous xylanase production by the auxotrophic strains in defined medium was critically dependent on the availability of amino acids, as extracellular xylanase production increased dramatically when amino acids were over-consumed from the medium to the point of saturating the cell. Saturation with amino acids, indicated by an increased leakage of amino acids from the cell, was thus a prerequisite for high level of heterologous; protein production by the auxotrophic ...
TY - JOUR. T1 - Penicillium purpurogenum produces a novel, acidic, GH3 beta-xylosidase. T2 - Heterologous expression and characterization of the enzyme. AU - Faúndez, Carolina. AU - Pérez, Rodrigo. AU - Ravanal, María Cristina. AU - Eyzaguirre, J.. PY - 2019/8/1. Y1 - 2019/8/1. N2 - Xylan, a component of plant cell walls, is composed of a backbone of β-1,4-linked xylopyranosyl units with a number of substituents. The complete degradation of xylan requires the action of several enzymes, among them β-xylosidase. The fungus Penicillium purpurogenum secretes a number of enzymes participating in the degradation of xylan. In this study, a β-xylosidase from this fungus was expressed in Pichia pastoris, and characterized. This enzyme (Xyl2) is a member of glycoside hydrolase family 3; it consists of a sequence of 792 residues including a signal peptide of 20 residues, with a theoretical molecular mass for the mature protein of 84.2 KDa and an isoelectric point of 5.07. The highest identity with a ...
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Xylan, comprising a xylose backbone with substituted sugar units, is the most abundant hemicellulose of secondary cell walls of higher plants, where its interactions with lignin and cellulose confer structural rigidity to the cell wall. Understanding the lignin-xylan interactions may enable development of plants with novel cell wall characteristics, potentially beneficial for production of pulp and chemicals. In this work, fungal xylan-degrading enzymes, including FC1, DFC2 and DFC4 were targeted for introduction into Arabidopsis thaliana and aspen under control of the wood specific promoter to investigate their effect on xylan structure and lignin-xylan interactions. Furthermore, a signal peptide of a secreted cellulase was fused to enzymes sequences in FC1 at N-terminus for targeting of recombinant enzymes to the cell wall whereas other constructs used native fungal SP. GUS reporter staining assay of hybrid aspen showed that the promoter used exhibits wood specific expression. Confocal ...
Domain architecture and assignment details (superfamily, family, region, evalue) for gi|15614886|ref|NP_243189.1| from Bacillus halodurans C-125. Plus protein sequence and external database links.
XYLATHIN® xylanase product performs across a wider temperature and pH range than competitive products, allowing easier operation without a loss in productivity through the normal process variability of day-to-day operations. XYLATHIN® xylanase is able to achieve a more rapid viscosity reduction in a shorter time than competitive products. In addition, XYLATHIN® xylanase reduces water retention in distillers dried grains with solubles (DDGS) better than competitor products and at a significantly lower dose. The ability of this product to reduce water retention has been shown to significantly reduce energy consumption during drying of DDGS in commercial fuel ethanol production. Source ...
Microbial communities from cow rumen are known for their ability to degrade diverse plant polymers at high rates. In this work, we identified 15 hydrolases through an activity-centred metagenome analysis of a fibre-adherent microbial community from dairy cow rumen. Among them, 7 glycosyl hydrolases (GHs) and 1 feruloyl esterase were successfully cloned, expressed, purified and characterised. The most striking result was a protein of GH family 43 (GHF43), hereinafter designated as R_09-02, which had characteristics very distinct from the other proteins in this family with mono-functional bxylosidase, a-xylanase, a-L-arabinase and a-L-arabinofuranosidase activities. R_09-02 is the first multifunctional enzyme to exhibit b-1,4 xylosidase, a-1,5 arabinofur(pyr)anosidase, b-1,4 lactase, a-1,6 raffinase, a-1,6 stachyase, b-galactosidase and a- 1,4 glucosidase activities. The R_09-02 protein appears to originate from the chromosome of a member of Clostridia, a class of phylum Firmicutes, members of ...
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The seemingly minimal disparities between TAXI-IA and rTAXI-IIA, and between the enzyme-inhibitor complexes, suggest that the inhibition strength and specificity of TAXI-IA/TAXI-IIA reside in the subtle difference of only a few amino acid residues. In this study, in-depth analysis of the enzyme-inhibitor complexes allowed identification of two structural features that determine the xylanase-TAXI interaction.. First, based on the structural analysis provided here, the stronger inhibition of ANX than of BSX by TAXI-I, as reported by Gebruers et al. and Fierens et al. [1,19] (Table 1), can be explained as follows. Figure 3A,C shows that the orientation of the His374 side-chain differs between the ANX·TAXI-IA and BSX·TAXI-IA complexes. In contrast to the conformational change observed in TAXI-IA for this His374TAXI-IA upon complexation with ANX [21], in the BSX·TAXI-IA complex the side-chain has an orientation identical to that in the uncomplexed structure. The basis for the (re)orientation of ...
Buy high purity insoluble AZCL-Xylan (Birchwood) for identification of enzyme activities in research, microbiological enzyme assays in vitro diagno...
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 ...
Tree of glycosyl hydrolases of the GH13 family. Full gene and species names and taxonomic positions are given in Additional file 3: Table S3. GH13 subfamilies [
Shares of Xylan plunged a day after the maker of computer-networking equipment reported fourth-quarter results failed to meet analysts expectations.
ஸ்பெல்ட் (Spelt இத்தாலியில்,Farro செர்மனியில் Dinkle) என்ற தானியம் கோதுமை போன்றதே. கோதுமையின் மூதாதையினரிடமிருந்து ஸ்பெல்டாக மாறியது. இதூ கோதுமையின் நெருங்கிய உறவினர். கோதுமையைவிட சற்று நீளமாகவும், கூர்முனைகளைக் கொண்டும், சிவப்பு நிற குளிர்கால கோதுமைபோல இருக்கும் இதனைக் குளிர்காலத்தில் அறுவடை செய்வர். இதன் மீதான உமியானது மிகவும் அடர்த்தியாக இருக்கும். இதனால் பூஞ்சையாலும் ...
A genomic library of Pseudomonas fluorescens subsp. cellulosa DNA constructed in pUC18 and expressed in Escherichia coli was screened for recombinants expressing 4-methylumbelliferyl beta-D-glucoside hydrolysing activity (MUGase). A single MUGase-positive clone was isolated. The MUGase hydrolysed cellobiose, cellotriose, cellotetraose, cellopentaose and cellohexaose to glucose, by sequentially cleaving glucose residues from the non-reducing end of the cello-oligosaccharides. The Km values for cellobiose and cellohexaose hydrolysis were 1.2 mM and 28 microM respectively. The enzyme exhibited no activity against soluble or insoluble cellulose, xylan and xylobiose. Thus the MUGase is classified as a 1,4-beta-D-glucan glucohydrolase (EC 3.2.1.74) and is designated 1,4-beta-D-glucan glucohydrolase D (CELD). When expressed by E. coli, CELD was located in the cell-envelope fraction; a significant proportion of the native enzyme was also associated with the cell envelope when synthesized by its ...
A novel hemicellulase-producing fungal strain was isolated from a local soil sample. The organism is identified as Aspergillus fumigatus based on ribosomal RNA analyses. The Aspergillus strain, designated as 2NB, produces both enzymes acting on xylan backbone (xylanase and β-xylosidase), and those acting on side chains (or accessory enzymes) notably α-arabinofuranosidase and acetyl-xylan esterase. The Asperigillus hemicellulases are characterized as having relatively low xylanase and β-xylosidase activities but high side chain removal activities. The activity ratio of side-chain acting enzymes to xylanase is higher than that of the Multifect enzyme, a commercial hemicellulase product. The potential of the novel hemicellulases in lignocelluloses bioprocessing was demonstrated with alkaline-pretreated switchgrass as lignocellulose substrate with hemicellulase supplemented with a ratio of xylanase activity to filter paper unit of 2:1. Supplement of Aspergillus hemicellulases to commercial ...
Xylan, a major component of plant hemicellulose, is a complex, highly branched heteropolymer. Endo-β-1,4-xylanases (EC 3.2.1.8) are glycosidases that cleave the internal β-1,4-xylosidic bonds of the main chain of xylan and produce unbranched or branched xylooligosaccharides (1). Due to the complexity of the xylan structure, endo-β-1,4-xylanases are diverse in sequences, structures, hydrolytic activities, and enzymatic properties. They are distributed in glycoside hydrolase (GH) families 5, 7, 8, 10, 11, and 43. Among endo-β-1,4-xylanases, those from GH family 10 (GH10) and GH11 have been studied in more detail. GH10 xylanases have an (α/β)8 barrel structure (2), while GH11 xylanases have a β-jelly roll structure (3). Despite their different structures, both enzyme families adopt the catalytic mechanism of anomeric retention to release xylooligosaccharides from xylan (2, 3).. The endo-β-1,4-xylanases in GH family 8 reported so far include XylY from Bacillus sp. strain KK-1 (4), PhXyl from ...
In this paper, the improvement of a fed-batch fermentation from the point of view of an industrial xylanase production process is described. The Bacillus strain chosen for this study is able to produce high quantities of a xylanase that is suitable to be used as bleach boost agent in chlorine-free bleaching sequences of paper pulp. It was found that xylo-oligosaccharides hydrolysis products from xylan by xylanase action were indispensable for induction of the enzyme synthesis, but that their presence in quantities of only 0.1g dm^-3 xylose equivalents led to catabolite repression. A substrate-limited fed-batch process, that is the most adapted, was furthermore improved with regard to nutrient requirement of the microorganism, especially the nitrogen source. A process with constant supply of a culture medium containing xylan, peptone and mineral nitrogen was able to produce 20240nkatcm^-3 with a productivity of 910nkatcm^-3 h^-1, which places the process among the best ever reported. ...
The aim of this study was to gain a comprehensive understanding of how viable SAN progeny produces higher levels of xylanases [17]. We focused on candidate TFs exhibiting differential expression levels between SAN and euploid progeny (six TF-encoding genes: ID in jgi,Trire2: 106677, 65854, 111446, 68930, 111515, 36913), as well as another candidate TF, SxlR. We confirmed that SxlR is a negative regulator of GH11 family xylanases. However, overexpression of the other six tested TFs had no effect on the xylanase activity. It seems that the segmental aneuploidy did not result in a change in sxlr gene copy number; however, it is still unknown whether segmental aneuploidy affects the expression of sxlr in SAN progeny.. Recently, another negative regulator of hemi-cellulase, xylanase promoter-binding protein 1 (Xpp1) was reported in T. reesei [18]. Xpp1 regulates transcription of hemi-cellulase genes only at later stages of cultivation. There was no significant difference in xylanase activity between ...
Various enzymatic cocktails were produced from two Trichoderma reesei strains, a cellulase hyperproducer strain and a strain with β-glucosidase activity overexpression. By using various carbon sources (lactose, glucose, xylose, hemicellulosic hydrolysate) for strains growth, contrasted enzymatic activities were obtained. The enzymatic cocktails presented various levels of efficiency for the hydrolysis of cellulose Avicel into glucose, in presence of xylans, or not. These latter were also hydrolyzed with different extents according to cocktails. The most efficient cocktails (TR1 and TR3) on Avicel were richer in filter paper activity (FPU) and presented a low ratio FPU/β-glucosidase activity. Cocktails TR2 and TR5 which were produced on the higher amount of hemicellulosic hydrolysate, possess both high xylanase and β-xylosidase activities, and were the most efficient for xylans hydrolysis. When hydrolysis of Avicel was conducted in presence of xylans, a decrease of glucose release occurred for all