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construction of a beta-glucosidase expression system using the multistress-tolerant yeast issatchenkia orientalis.we demonstrate the value of the thermotolerant yeast issatchenkia orientalis as a candidate microorganism for bioethanol production from lignocellulosic biomass with the goal of consolidated bioprocessing. the i. orientalis mf-121 strain is acid tolerant, ethanol tolerant, and thermotolerant, and is thus a multistress-tolerant yeast. to express heterologous proteins in i. orientalis, we constructed a transformation system for the mf-121 strain and then isolated the promoters of tdh1 and pgk1, tw ...201020467739
gene cloning and characterization of a novel thermophilic esterase from fervidobacterium nodosum rt17-b1.a bioinformatic screening of the genome of the thermophilic bacterium fervidobacterium nodosum rt17-b1 for esterhydrolyzing enzymes revealed a putative bacterial esterase (fne) encoded by fond_1301 with typical gdsl family motifs. to confirm its putative esterase function, the fne gene was cloned, functionally expressed in escherichia coli, and purified to homogeneity. recombinant fne exhibited the highest esterase activity of 14,000 u/mg with p-nitrophenyl acetate (pnpc(2)) as substrate. the ca ...201020383468
ethanol production from cellulosic materials using cellulase-expressing yeast.we demonstrate direct ethanol fermentation from amorphous cellulose using cellulase-co-expressing yeast. endoglucanases (eg) and cellobiohydrolases (cbh) from trichoderma reesei, and beta-glucosidases (bgl) from aspergillus aculeatus were integrated into genomes of the yeast strain saccharomyces cerevisiae mt8-1. bgl was displayed on the yeast cell surface and both eg and cbh were secreted or displayed on the cell surface. all enzymes were successfully expressed on the cell surface or in culture ...201020349451
evaluation of enzyme mixtures in releasing fermentable sugars from pre-pulping extracts of mixed northeast hardwoods.one near-term option to developing a forest product biorefinery is to derive pre-pulping extract from incoming wood chips before the main pulping step. the release of monomer sugars from a xylan-rich extract, creating a fermentable substrate is a prerequisite for utilization of pre-pulping extract for production of ethanol or other value-added products. this study examined the individual and mixture efficiencies of two hemicellulolytic microbial enzymes and two xylanase preparations in catalyzin ...201020084471
aspergillusol a, an alpha-glucosidase inhibitor from the marine-derived fungus aspergillus aculeatus.a new tyrosine-derived metabolite, aspergillusol a (4), was isolated on a gram scale, together with a methyl ester of 4-hydroxyphenylpyruvic acid oxime (5) and secalonic acid a, from the marine-derived fungus aspergillus aculeatus cri323-04. the tetraol in 4 was identified as erythritol by comparison of the 1h nmr spectrum of its benzoylated derivative with those of benzoylated erythritol (7) and d-threitol (8), as well as by cellulose-based chiral hplc analysis. aspergillusol a (4) selectively ...200919824618
effect of cosolvents on the structural stability of endoglucanase from aspergillus aculeatus.the effects of cosolvents such as sucrose, glycerol, and sorbitol on endoglucanase have been studied by activity, circular dichroic spectroscopy, fluorescence, and apparent thermal transition temperature measurements. the endoglucanase activity increased by 4-fold at 40% cosolvent concentration under optimum conditions. the endoglucanase lost 50% of its activity when exposed to 90 degrees c for more than 30 min (1 h). in the presence of cosolvents, it maintained its original activity and native ...200919813733
d-lactic acid production from cellooligosaccharides and beta-glucan using l-ldh gene-deficient and endoglucanase-secreting lactobacillus plantarum.in order to achieve direct fermentation of an optically pure d: -lactic acid from cellulosic materials, an endoglucanase from a clostridium thermocellum (cela)-secreting plasmid was introduced into an l: -lactate dehydrogenase gene (ldhl1)-deficient lactobacillus plantarum (ldhl1) bacterial strain. cela expression and its degradation of beta-glucan was confirmed by western blot analysis and enzyme assay, respectively. although the cela-secreting ldhl1 assimilated cellooligosaccharides up to cell ...201019597813
heterologous expression and optimized production of an aspergillus aculeatus endo-1,4-beta-mannanase in yarrowia lipolytica.the aspergillus aculeatus mrc11624 man1 gene, encoding an endo-beta-1,4-mannanase, was cloned and expressed in the promising heterologous enzyme producer, the ascomycetous yeast yarrowia lipolytica. both single- and multi-copy transformants were constructed, and the secretion of the enzyme was evaluated as an in-frame fusion with the lip2 secretion signal, as well as with its natural secretion signal. in shake-flask analysis, the highest volumetric enzyme activity (13,073 nkat/ml) and specific e ...200919507068
development of a homologous transformation system for aspergillus aculeatus based on the sc gene encoding atp-sulfurylase.a homologous transformation system was developed using the endogenous atp-sulfurylase gene, aasc, as a selectable marker in aspergillus aculeatus. spontaneous mutation was proved to be beneficial in isolating aasc-deficient mutants. molecular analysis of sc(+) transformants revealed that the frequency of single copy integration at atp-sulfurylase locus was more than 40%.200919420695
regulation of the display ratio of enzymes on the saccharomyces cerevisiae cell surface by the immunoglobulin g and cellulosomal enzyme binding domains.we constructed a novel cell surface display system to control the ratio of target proteins on the saccharomyces cerevisiae cell surface, using two pairs of protein-protein interactions. one protein pair is the z domain of protein a derived from staphylococcus aureus and the fc domain of human immunoglobulin g. the other is the cohesin (coh) and dockerin (dock) from the cellulosome of clostridium cellulovorans. in this proposed displaying system, the scaffolding proteins (fusion proteins of z and ...200919411409
production of the aspergillus aculeatus endo-1,4-beta-mannanase in a. niger.the beta-mannanase gene (man1) from aspergillus aculeatus mrc11624 (izuka) was patented for application in the coffee industry. for production of the enzyme, the gene was originally cloned and expressed in saccharomyces cerevisiae. however the level of production was found to be economically unfeasible. here we report a 13-fold increase in enzyme production through the successful expression of beta-mannanase of aspergillus aculeatus mrc11624 in aspergillus niger under control of the a. niger gly ...200919277742
gelation of high-methoxy pectin by enzymic de-esterification in the presence of calcium ions: a preliminary evaluation.cohesive gels have been obtained by de-esterification of 1.0wt% high-methoxy citrus pectin (degree of esterification approximately 68%) in the presence of ca(2+) cations, using a commercial preparation (novoshape) of fungal methyl esterase cloned from aspergillus aculeatus. a convenient rate of network formation (gelation within approximately 30min) was achieved at an enzyme concentration of 0.2 peu/g pectin. at a ca(2+)-concentration of 40mm and incubation temperature of 20 degrees c, severe sy ...200919100969
response surface methodology: synthesis of short chain fructooligosaccharides with a fructosyltransferase from aspergillus aculeatus.a transferase was isolated, purified and characterised from aspergillus aculeatus. the enzyme exhibited a ph and temperature optima of 6.0 and 60 degrees c, respectively and under such conditions remained stable with no decrease in activity after 5h. the enzyme was purified 7.1 fold with a yield of 22.3% and specific activity of 486.1umg(-1) after dialysis, concentration with polyethyleneglycol (30%) and deae-sephacel chromatography. it was monomeric with a molecular mass of 85kda and k(m) and v ...200919028090
extraction of green labeled pectins and pectic oligosaccharides from plant byproducts.green labeled pectins were extracted by an environmentally friendly way using proteases and cellulases being able to act on proteins and cellulose present in cell walls. pectins were isolated from different plant byproducts, i.e., chicory roots, citrus peel, cauliflower florets and leaves, endive, and sugar beet pulps. enzymatic extraction was performed at 50 degrees c for 4 h, in order to fulfill the conditions required for microbiological safety of extracted products. high methoxy (hm) pectins ...200818788816
improvement of aspergillus oryzae for hyperproduction of endoglucanase: expression cloning of cmc-1 gene of aspergillus aculeatus.fi-carboxymethylcellulase (cmc1; family 12) is one of the endoglucanases of aspergillus aculeatus and consists of single polypeptide chain of 221 amino acids. the cmc1 gene was expressed in aspergillus oryzae niad300 (niad-) under promoter 8142. the plasmid pcmg14 carrying the cmc1 gene at psti site was used as a source of the gene (920 bp) and aspergillus oryzae was successfully transformed by the plasmid pnan-cmc1 (harboring cmc1 gene). the plasmid was integrated in aspergillus oryzae niad300 ...200818661108
characterization of an alpha-l-rhamnosidase from aspergillus kawachii and its gene.an alpha-l-rhamnosidase was purified by fractionating a culture filtrate of aspergillus kawachii grown on l-rhamnose as the sole carbon source. the alpha-l-rhamnosidase had a molecular mass of 90 kda and a high degree of n-glycosylation of approximately 22%. the enzyme exhibited optimal activity at ph 4.0 and temperature of 50 degrees c. further, it was observed to be thermostable, and it retained more than 80% of its original activity following incubation at 60 degrees c for 1 h. its t (50) val ...200818633609
two novel species of aspergillus section nigri from thai coffee beans.two novel species of aspergillus section nigri from thai coffee beans are described as aspergillus aculeatinus sp. nov. and aspergillus sclerotiicarbonarius sp. nov. their taxonomic status was determined using a polyphasic taxonomic approach with phenotypic (morphology and extrolite profiles) and molecular (beta-tubulin, internal transcribed spacer and calmodulin gene sequences) characteristics. a. aculeatinus sp. nov. is a uniseriate species with a similar morphology to aspergillus aculeatus an ...200818599725
evidence for a blockwise distribution of acetyl groups onto homogalacturonans from a commercial sugar beet (beta vulgaris) pectin.commercial acid-extracted sugar beet pectin was extensively hydrolysed using an endo-polygalacturonase (anpgi from aspergillus niger or anpgii from a. niger or fmpg from fusarium moniliforme) in combination with aspergillus aculeatus pectin methyl-esterase (aapme). the homogalacturonan-derived oligogalacturonates released were quantified by high-performance anion-exchange chromatography and their structure determined by mass spectrometry. the different endo-polygalacturonases exhibited variable ...200818448141
lactic fermentation of cellobiose by a yeast strain displaying beta-glucosidase on the cell surface.the aspergillus aculeatus beta-glucosidase 1 (bgl1) gene was expressed in a lactic-acid-producing saccharomyces cerevisiae strain to enable lactic fermentation with cellobiose. the recombinant beta-glucosidase enzyme was expressed on the yeast cell surface by fusing the mature protein to the c-terminal half region of the alpha-agglutinin. the beta-glucosidase expression plasmids were integrated into the genome. three strong promoters of s. cerevisiae, the tdh3, pgk1, and pdc1 promoters, were use ...200818443785
synthesis of oligosaccharides derived from lactulose and pectinex ultra sp-l.the beta-galactosidase activity of the commercial enzymatic preparation pectinex ultra sp-l derived from aspergillus aculeatus has been used to hydrolyze and transgalactosylate the prebiotic carbohydrate lactulose. during this reaction, new oligosaccharides derived from lactulose have been detected by high-performance anion-exchange chromatography with pulsed amperometric detection (hpaec-pad). the presence of the trisaccharide 6'-galactosyl-lactulose, the major compound formed, has been confirm ...200818412359
aspergillus uvarum sp. nov., an uniseriate black aspergillus species isolated from grapes in europe.a novel species, aspergillus uvarum sp. nov., is described within aspergillus section nigri. this species can be distinguished from other black aspergilli based on internal transcribed spacers (its), beta-tubulin and calmodulin gene sequences, by aflp analysis and by extrolite profiles. aspergillus uvarum sp. nov. isolates produced secalonic acid, common to other aspergillus japonicus-related taxa, and geodin, erdin and dihydrogeodin, which are not produced by any other black aspergilli. none of ...200818398215
characterization of a new rhamnogalacturonan acetyl esterase from bacillus halodurans c-125 with a new putative carbohydrate binding domain.bh1115 is a gene from bacillus halodurans strain c-125 that hypothetically encodes a rhamnogalacturonan acetyl esterase (rgae) of the ce-12 family. as confirmation, this gene was cloned, and the product was expressed in escherichia coli strain rosetta (de3) cells and purified. the enzyme obtained was monomeric, with a molecular mass of 45 kda, and exhibited alkaliphilic properties. a study of the inhibition of the activity by some modulators confirmed that the catalytic triad for the esterase ac ...200818083818
a xyloglucan-specific family 12 glycosyl hydrolase from aspergillus niger: recombinant expression, purification and characterization.a new gh12 (glycosyl hydrolase 12) family xeg [xyloglucan-specific endo-beta-1,4-glucanase (ec 3.2.1.151)] from aspergillus niger, anxeg12a, was overexpressed, purified and characterized. whereas seven xyloglucanases from gh74 and two xyloglucanases from gh5 have been characterized previously, this is only the third characterized example of a gh12 family xyloglucanase. gh12 enzymes are structurally and mechanistically distinct from gh74 enzymes. although over 100 gh12 sequences are now available ...200818072936
yest: a new rhamnogalacturonan acetyl esterase from bacillus subtilis.yest, a putative protein from bacillus subtilis atcc 6633 that has been provisionally classified as a rhamnogalacturonan acetyl esterase (rgae) in ce-12 family, was cloned, expressed in escherichiacoli rosetta (de3), and purified. the enzyme is monomeric with a molecular mass of 37 kda and presents thermophilic properties similar to rgae from aspergillus aculeatus, although yest is more alkaliphilic. the study of inhibitors confirmed the importance of the his and the nucleophilic ser for the est ...200817957779
tannase production by aspergillus aculeatus dbf9 through solid-state fermentation.tannase an industrially important enzyme was produced by aspergillus aculeatus dbf9 through a solid-state fermentation (ssf). the organism produced good amount of enzyme and gallic acid in wheat bran among the solid substrate used in ssf. maximum enzyme and gallic acid production occurred in 5% tannic acid after 72 h. eighty percent initial substrate moisture and 30 degrees c temperature was found suitable for tannase production.200717899795
purification and characterization of a new endoglucanase from aspergillus aculeatus.endoglucanase has been isolated from aspergillus aculeatus. the purified enzyme showed a single band and had a molecular weight of 45,000 da as indicated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with a specific activity of 1.4 units/mg. the purified enzyme was identified as endoglucanase, showing a high specific activity toward cm-cellulose and low specific activity toward avicel. the activity of the isolated enzyme was optimum at a ph of 5.0 and temperature of 40 degrees c, ...200717685540
development of an efficient production method for beta-mannosidase by the creation of an overexpression system in aspergillus aculeatus.to develop an overexpression system in aspergillus aculeatus in order to establish an efficient overproduction method of beta-mannosidase (manb).200717651209
restricted cell elongation in arabidopsis hypocotyls is associated with a reduced average pectin esterification level.cell elongation is mainly limited by the extensibility of the cell wall. dicotyledonous primary (growing) cell walls contain cellulose, xyloglucan, pectin and proteins, but little is known about how each polymer class contributes to the cell wall mechanical properties that control extensibility.200717572910
plant cell wall degradation by saprophytic bacillus subtilis strains: gene clusters responsible for rhamnogalacturonan depolymerization.plant cell wall degradation is a premier event when bacillus subtilis, a typical saprophytic bacterium, invades plants. here we show the degradation system of rhamnogalacturonan type i (rg-i), a component of pectin from the plant cell wall, in b. subtilis strain 168. strain 168 cells showed a significant growth on plant cell wall polysaccharides such as pectin, polygalacturonan, and rg-i as a carbon source. dna microarray analysis indicated that three gene clusters (yesopqrstuvwxyz, ytepqrst, an ...200717449691
improving retting of fibre through genetic modification of flax to express pectinases.flax (linum usitatissimum l.) is a raw material used for important industrial products. linen has very high quality textile properties, such as its strength, water absorption, comfort and feel. however, it occupies less than 1% of the total textile market. the major reason for this is the long and difficult retting process by which linen fibres are obtained. in retting, bast fibre bundles are separated from the core, the epidermis and the cuticle. this is accomplished by the cleavage of pectins ...200817372706
variability in the structure of rye flour alkali-extractable arabinoxylans.the variability in rye flour alkali-extractable arabinoxylan (ae-ax) structures was examined by extensive fractionation and enzymic degradation studies. ax were isolated from destarched rye water-unextractables by sequential extraction with saturated barium hydroxide solution, water, 1.0 m sodium hydroxide, and water. the isolated ae-ax contained ca. 51% ax with an arabinose to xylose (a/x) ratio of 0.71. fractionation of the isolated ae-ax by ethanol precipitation yielded a range of ae-ax fract ...200717274627
cloning, functional expression and characterization of aspergillus sulphureus beta-mannanase in pichia pastoris.using rt-pcr and rapid amplication of cdna ends (race) techniques, a 1345bp full-length cdna fragment was obtained from aspergillus sulphureus. the gene, designated mann, codes for a 383-residue with a calculated mass of 41,389da. mann displayed amino acid sequence similarity to the beta-mannanase of aspergillus aculeatus and trichoderma reesei, members of the glycoside hydrolase family 5. the recombinant beta-mannanase gene was successfully expressed in a fully active form in pichia pastoris. s ...200717194495
purification and kinetic characterization of a fructosyltransferase from aspergillus aculeatus.a fructosyltransferase present in pectinex ultra sp-l, a commercial enzyme preparation from aspergillus aculeatus, was purified to 107-fold and further characterised. the enzyme was a dimeric glycoprotein (20% (w/w) carbohydrate content) with a molecular mass of around 135 kda for the dimer. optimal activity/stability was found in the ph range 5.0-7.0 and at 60 degrees c. it was stable or slightly activated (upto 1.4-fold) in the presence of reducing agents, such as dithiothreitol and 2-mercapto ...200717056145
effect of temperature and high pressure on the activity and mode of action of fungal pectin methyl esterase.pectin was de-esterified with purified recombinant aspergillus aculeatus pectin methyl esterase (pme) during isothermal-isobaric treatments. by measuring the release of methanol as a function of treatment time, the rate of enzymatic pectin conversion was determined. elevated temperature and pressure were found to stimulate pme activity. the highest rate of pme-catalyzed pectin de-esterification was obtained when combining pressures in the range 200-300 mpa with temperatures in the range 50-55 de ...200617022669
an its-rflp method to identify black aspergillus isolates responsible for ota contamination in grapes and wine.ochratoxigenic mycobiota in grapes from representative wine regions in valencia was identified. black aspergilli were predominant among the different aspergillus spp. isolated. restriction digestion analysis of the its products was tested as a rapid method to identify isolates of black aspergillus species from grapes. restriction endonuclease digestion of the its products using the endonucleases hhai, nlaiii and rsai, distinguished five types of restriction fragment length polymorphism (rflp) co ...200716870292
gene duplication event in family 12 glycosyl hydrolase from phytophthora spp.a total of 18 paralogs of xyloglucan-specific endoglucanases (egls) from the glycosyl hydrolase family 12 were identified and characterized in phytophthora sojae and phytophthora ramorum. these genes encode predicted extracellular enzymes, with sizes ranging from 189 to 435 amino acid residues, that would be capable of hydrolyzing the xyloglucan component of the host cell wall. in two cases, four and six functional copies of these genes were found in tight succession within a region of 5 and 18 ...200616784880
beet sugar syrup and molasses as low-cost feedstock for the enzymatic production of fructo-oligosaccharides.sugar syrup and molasses from beet processing containing 620 and 570 mg/ml sucrose, respectively, were assayed as low-cost and available substrates for the enzymatic synthesis of fructo-oligosaccharides (foss). a commercial pectinase (pectinex ultra sp-l, from aspergillus aculeatus) characterized by the presence of a transfructosylating activity was used as a biocatalyst. the fos production increased when lowering the initial ph value of syrup (7.5) and molasses (8.9) to 5.5. sugar syrup and mol ...200616608216
overexpression of aspergillus aculeatus cellobiohydrolase i in aspergillus oryzae.to express the cbhi gene, encoding aspergillus aculeatus cellobiohydrolase i (cbhi), in aspergillus oryzae, a plasmid was constructed. the strain that displayed the strongest cbhi activity among the transformants produced about 941 mg/l in liquid culture. it was confirmed by a pcr method that the plasmid was integrated at the niad locus.200316233469
cloning and transcription analysis of the aspergillus aculeatus no. f-50 endoglucanase 2 (cmc2) gene.the cmc2 gene, coding for an endoglucanase 2 (cmc2) of aspergillus aculeatus, was cloned using both genomic and cdna libraries, and sequenced. the gene consists of 1230 bp encoding a protein of 410 amino acid residues with a molecular mass of 43,697 da. the cmc2, composed of an n-terminal catalytic domain belonging to the family 5 of glycosyl hydrolases and a c-terminal cellulose-binding domain (cbd) belonging to the family i of cbds, showed identity with other fungal endoglucanases, particularl ...200216233338
overexpression and purification of aspergillus aculeatus beta-mannosidase and analysis of the integrated gene in aspergillus oryzae.an expression plasmid for the manb gene encoding aspergillus aculeatus beta-d-mannosidase (manb) was constructed by using an expression vector carrying an improved promoter. after transformation of a. oryzae by the plasmid, several transformants formed colonies emitting fluorescence on a plate containing 4-methylumbelliferyl beta-d-mannopyranoside (mu-man) under uv-irradiation. the transformant that displayed the strongest fluorescence, named a. oryzae bmn1, produced about 270 mg manb/l in liqui ...200116233072
cell surface engineering of yeast: construction of arming yeast with biocatalyst.a cell surface engineering system of yeast saccharomyces cerevisiae has been established and novel yeasts armed by biocatalysts (enzymes-glucoamylase, alpha-amylase, cm-cellulase, beta-glucosidase, and lipase), termed "arming yeasts", were constructed. the gene encoding rhizopus oryzae glucoamylase with its secretion signal peptide was fused with the gene encoding the c-terminal half of yeast alpha-agglutinin and expressed in s. cerevisiae. glucoamylase was shown to be displayed on the cell surf ...200016232831
purification and properties of glucose 6-phosphate dehydrogenase from aspergillus aculeatus.glucose 6-phosphate dehydrogenase (ec 1.1.1.49) was purified from aspergillus aculeatus, a filamentous fungus previously isolated from infected tongue of a patient. the enzyme, apparently homogeneous, had a specific activity of 220 units mg(-1), a molecular weight of 105,000 +/- 5,000 dal by gel filtration and subunit size of 52,000 +/- 1,100 dal by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. the substrate specificity was extremely strict, with glucose 6-phosphate (g6p) being oxi ...200516202239
complete 1h and 13c nmr assignments of aurasperone a and fonsecinone a, two bis-naphthopyrones produced by aspergillus aculeatus.complete assignments of 1h and 13c nmr chemical shifts of the polyketides aurasperone a and fonsecinone a were made by means of nuclear overhauser enhancement and heteronuclear nmr correlation experiments. these compounds were isolated for the first time from aspergillus aculeatus, an endophytic fungus obtained from leaves of melia azedarach(meliaceae).200516155971
bifidobacterium longum endogalactanase liberates galactotriose from type i galactans.a putative endogalactanase gene classified into glycoside hydrolase family 53 was revealed from the genome sequence of bifidobacterium longum strain ncc2705 (schell et al., proc. natl. acad. sci. usa 99:14422-14427, 2002). since only a few endo-acting enzymes from bifidobacteria have been described, we have cloned this gene and characterized the enzyme in detail. the deduced amino acid sequence suggested that this enzyme was located extracellularly and anchored to the cell membrane. gala was clo ...200516151143
enzymic degradability of hull-less barley flour alkali-solubilized arabinoxylan fractions by endoxylanases.the impacts of the arabinose to xylose (a/x) ratio of arabinoxylans (ax) and the endoxylanase substrate specificity on the enzymic degradability of hull-less barley flour ax by endoxylanases were studied by using alkali-solubilized ax (as-ax) fractions with different a/x ratio, on the one hand, and glycoside hydrolase family 10 and 11 endoxylanases of aspergillus aculeatus (xaa) and bacillus subtilis (xbs), respectively, on the other hand. as-ax were obtained by saturated barium hydroxide treatm ...200516131137
the in situ observation of the temperature and pressure stability of recombinant aspergillus aculeatus pectin methylesterase with fourier transform ir spectroscopy reveals an unusual pressure stability of beta-helices.the stability of recombinant aspergillus aculeatus pme (pectin methylesterase), an enzyme with high beta-helix content, was studied as a function of pressure and temperature. the conformational stability was monitored using ftir (fourier transform ir) spectroscopy whereas the functional enzyme stability was monitored by inactivation studies. protein unfolding followed by amorphous aggregation, which makes the process irreversible, was observed at temperatures above 50 degrees c. this could be co ...200516050809
purification and characterization of a xip-type endoxylanase inhibitor from rice (oryza sativa).a rice xip-type inhibitor was purified by affinity chromatography with an immobilized aspergillus aculeatus family 10 endoxylanase. rice xip is a monomeric protein, with a molecular mass of ca. 32 kda and a pi of ca. 5.6. its n-terminal amino acid sequence was identical to that of a rice chitinase homologue, demonstrating the difficulty when using sequence information to differentiate between endoxylanase inhibitors and (putative) chitinases in rice. rice xip inhibited different endoxylanases to ...200515895691
dna-based characterization of ochratoxin-a-producing and non-producing aspergillus carbonarius strains from grapes.using molecular methods, a total of 189 strains of black aspergilli, including aspergillus carbonarius and uniseriate species (aspergillus aculeatus, aspergillus japonicus), were studied in order to characterize species responsible for ochratoxin a (ota) contamination of grapes from europe and israel. sixty-six strains were morphologically identified as belonging to the uniseriate species and 123 as a. carbonarius. none of the uniseriate species were able to produce ota. from the a. carbonarius ...200515808942
production of bioavailable flavonoid glucosides in fruit juices and green tea by use of fungal alpha-l-rhamnosidases.flavonoid glucosides have been reported to be more bioavailable than their rutinoside counterparts. the aim of this study is to describe a first step in the use of alpha-l-rhamnosidases (rhaa and rhab) from aspergillus aculeatus as a way to produce functional beverages based on their potentially increased flavonoid bioavailability. blackcurrant juice (bcj), orange juice (oj), and green tea infusion (gt) were incubated with either rhaa or rhab at 30 degrees c for 10 h. aliquots of controls and en ...200415453678
the structure of endo-beta-1,4-galactanase from bacillus licheniformis in complex with two oligosaccharide products.the beta-1,4-galactanase from bacillus licheniformis (blgal) is a plant cell-wall-degrading enzyme involved in the hydrolysis of beta-1,4-galactan in the hairy regions of pectin. the crystal structure of blgal was determined by molecular replacement both alone and in complex with the products galactobiose and galactotriose, catching a first crystallographic glimpse of fragments of beta-1,4-galactan. as expected for an enzyme belonging to gh-53, the blgal structure reveals a (betaalpha)(8)-barrel ...200415312766
crystallization and preliminary x-ray studies of rhamnogalacturonase a from aspergillus aculeatus.recombinant rhamnogalacturonase a from aspergillus aculeatus has been crystallized and x-ray diffraction data has been collected. crystals were grown by the hanging-drop vapour-diffusion technique, under the conditions 10% peg 8000, 0.05 m kh(2)po(4) and 0.1 m sodium acetate buffered at ph 3.5. the crystals diffract beyond 2.0 a resolution and belong to one of the orthorhombic space groups i2(1)2(1)2(1) or i222, with the unit-cell parameters a = 62.9, b = 125.4 and c = 137.0 a. there is one mole ...199715299976
a comparison of three xylanases on the nutritive value of two wheats for broiler chickens.three xylanase products, xylanase a derived from thermomyces lanuginosus, xylanase b from humicola insolens and xylanase c from aspergillus aculeatus, were examined for their effects on the nutritive value of wheat. the study investigated the effects of enzyme addition to broiler diets based on a low-metabolisable-energy (me) wheat and a normal-me wheat, with the emphasis on changes in composition of the nsp along the digestive tract in broiler chickens. there were significant (p<0.01) enzyme an ...200415230987
rhamnogalacturonan lyase reveals a unique three-domain modular structure for polysaccharide lyase family 4.rhamnogalacturonan lyase (rg-lyase) specifically recognizes and cleaves alpha-1,4 glycosidic bonds between l-rhamnose and d-galacturonic acids in the backbone of rhamnogalacturonan-i, a major component of the plant cell wall polysaccharide, pectin. the three-dimensional structure of rg-lyase from aspergillus aculeatus has been determined to 1.5 a resolution representing the first known structure from polysaccharide lyase family 4 and of an enzyme with this catalytic specificity. the 508-amino ac ...200415135077
computer modeling of the rhamnogalacturonase-"hairy" pectin complex.the structure of a pectin-bound complex of rhamnogalacturonase was modeled to identify the amino acid residues involved in catalysis and substrate binding. the "hairy" region of pectin, represented by six repeating stretches of (1-->4)-d-galacturonate-(1-->2)-l-rhamnose dimer, was flexibly docked into the putative binding site of rhamnogalacturonase from aspergillus aculeatus whose x-ray structure is known. a search of the complex configurational space was performed using autodock for the dimeri ...200414997537
crystal packing in two ph-dependent crystal forms of rhamnogalacturonan acetylesterase.the glycoprotein rhamnogalacturonan acetylesterase from aspergillus aculeatus has been crystallized in two crystal forms, an orthorhombic and a trigonal crystal form. in the orthorhombic crystal form, the covalently bound carbohydrate at one of the two n-glycosylation sites is involved in crystal contacts. the orthorhombic crystal form was obtained at ph 5.0 and the trigonal crystal form at ph 4.5. in one case, the two crystal forms were found in the same drop at ph 4.7. the differences in cryst ...200414993671
synergistic saccharification, and direct fermentation to ethanol, of amorphous cellulose by use of an engineered yeast strain codisplaying three types of cellulolytic enzyme.a whole-cell biocatalyst with the ability to induce synergistic and sequential cellulose-degradation reaction was constructed through codisplay of three types of cellulolytic enzyme on the cell surface of the yeast saccharomyces cerevisiae. when a cell surface display system based on alpha-agglutinin was used, trichoderma reesei endoglucanase ii and cellobiohydrolase ii and aspergillus aculeatus beta-glucosidase 1 were simultaneously codisplayed as individual fusion proteins with the c-terminal- ...200414766607
transformation of aspergillus aculeatus using the drug resistance gene of aspergillus oryzae and the pyrg gene of aspergillus nidulans.transformation systems for aspergillus aculeatus has been developed, based on the use of the pyrithiamine resistance gene of aspergillus oryzae and the orotidine-5'-monophosphate decarboxylase gene (pyrg) of aspergillus nidulans. an a. aculeatus mutant which can be transformed effectively by the a. nidulans pyrg gene was isolated as a transformation host. this is the first report of transformation of a. aculeatus.200314730150
construction of a genetically modified wine yeast strain expressing the aspergillus aculeatus rhaa gene, encoding an alpha-l-rhamnosidase of enological interest.the aspergillus aculeatus rhaa gene encoding an alpha-l-rhamnosidase has been expressed in both laboratory and industrial wine yeast strains. wines produced in microvinifications, conducted using a combination of the genetically modified industrial strain expressing rhaa and another strain expressing a beta-glucosidase, show increased content mainly of the aromatic compound linalool.200314660415
impact of xylanases with different substrate selectivity on gluten-starch separation of wheat flour.the influence on wheat flour gluten-starch separation of a xylanase from aspergillus aculeatus (xaa) with hydrolysis selectivity toward water extractable arabinoxylan (we-ax) and that is not inhibited by wheat flour xylanase inhibitors was compared to that of a xylanase from bacillus subtilis (xbs) with hydrolysis selectivity toward water unextractable arabinoxylan (wu-ax) and that is inhibited by such inhibitors. xaa improved gluten agglomeration through degradation of we-ax and concomitant red ...200314640581
a screening method for endo-beta-1,4-xylanase substrate selectivity.endoxylanase (ec 3.2.1.8) substrate selectivity, i.e., its relative activity toward water-unextractable arabinoxylan (wu-ax) and water-extractable arabinoxylan (we-ax) substrates, is important for its functionality in biotechnological processes such as bread-making and gluten starch separation. a screening method for rapidly determining said substrate selectivity was developed. endoxylanase activity toward wu-ax was estimated by incubation of insoluble chromogenic substrate with a range of enzym ...200312842109
efficient isolation of genes differentially expressed on cellulose by suppression subtractive hybridization in agaricus bisporus.the production of cellulases on minimal medium in the edible mushroom agaricus bisporus is regulated by the carbon source: induced by cellulose and repressed by glucose. in order to isolate cellulose-growth specific sequences, a cdna library from a. bisporus using suppression subtractive hybridization (ssh) was constructed. northern blot analysis indicated that a high level of enrichment was achieved; 183 clones were isolated. a preliminary screen with cellulose-specific genes of a. bisporus (ce ...200312825511
structure of two fungal beta-1,4-galactanases: searching for the basis for temperature and ph optimum.beta-1,4-galactanases hydrolyze the galactan side chains that are part of the complex carbohydrate structure of the pectin. they are assigned to family 53 of the glycoside hydrolases and display significant variations in their ph and temperature optimum and stability. two fungal beta-1,4-galactanases from myceliophthora thermophila and humicola insolens have been cloned and heterologously expressed, and the crystal structures of the gene products were determined. the structures are compared to t ...200312761390
characterization of a tomato protein that inhibits a xyloglucan-specific endoglucanase.a basic, 51 kda protein was purified from suspension-cultured tomato and shown to inhibit the hydrolytic activity of a xyloglucan-specific endoglucanase (xeg) from the fungus aspergillus aculeatus. the tomato (lycopersicon esculentum) protein, termed xeg inhibitor protein (xegip), inhibits xeg activity by forming a 1 : 1 protein:protein complex with a ki approximately 0.5 nm. to our knowledge, xegip is the first reported proteinaceous inhibitor of any endo-beta-1,4-glucanase, including the cellu ...200312713539
[purification and properties of endoglucanases from aspergillus aculeatus sm-l22].the five endoglucanases(cmcase) components from aspergillus aculeatus sm-l22 were separated and purified by exclusion chromatography and ion-exchange chromatography. five components(eg ii-1, eg ii-2, eg iii-1, eg iii-2 and eg iv) had molecular weights of 38.7, 34.4, 31.4, 36.9 and 23.7 kd by sds-page, respectively, and ief showed their pi were ph < 3.5, < 3.5, 4.9, 4.4 and 5.0, respectively. all of them have maximum reactive activities at ph 3.5-4.0; and the optimum temperatures were 55 degrees ...200112552914
aspergillus aculeatus beta-1,4-galactanase: substrate recognition and relations to other glycoside hydrolases in clan gh-a.the three-dimensional structure of aspergillus aculeatus beta-1,4-galactanase (aagal), an enzyme involved in pectin degradation, has been determined by multiple isomorphous replacement to 2.3 and 1.8 a resolution at 293 and 100 k, respectively. it represents the first known structure for a polysaccharidase with this specificity and for a member of glycoside hydrolase family 53 (gh-53). the enzyme folds into a (beta/alpha)(8) barrel with the active site cleft located at the c-terminal side of the ...200212484750
direct and efficient production of ethanol from cellulosic material with a yeast strain displaying cellulolytic enzymes.for direct and efficient ethanol production from cellulosic materials, we constructed a novel cellulose-degrading yeast strain by genetically codisplaying two cellulolytic enzymes on the cell surface of saccharomyces cerevisiae. by using a cell surface engineering system based on alpha-agglutinin, endoglucanase ii (egii) from the filamentous fungus trichoderma reesei qm9414 was displayed on the cell surface as a fusion protein containing an rgshis6 (arg-gly-ser-his(6)) peptide tag in the n-termi ...200212324364
a stepwise optimization of crystals of rhamnogalacturonan lyase from aspergillus aculeatus.recombinant rhamnogalacturonan lyase from aspergillus aculeatus has been crystallized by a stepwise procedure and x-ray diffraction data have been collected. the crystals were grown using hanging-drop vapour-diffusion and microseeding techniques. crystals were obtained showing a flat plate morphology. the crystallization conditions were 20% peg 4000, 9% peg 400, 0.1 m (nh(4))(2)so(4) and 0.1 m sodium acetate ph 4.4. these crystals diffracted to a resolution of 1.5 a. the unit-cell parameters are ...200212136151
in muro fragmentation of the rhamnogalacturonan i backbone in potato (solanum tuberosum l.) results in a reduction and altered location of the galactan and arabinan side-chains and abnormal periderm development.rhamnogalacturonan (rg) i is a branched pectic polysaccharide in plant cell walls. rhamnogalacturonan lyase (ergl) from aspergillus aculeatus is able to cleave the rg i backbone at specific sites. transgenic potato (solanum tuberosum l.) plants were made by the introduction of the gene encoding ergl, under the control of the granule-bound starch synthase promoter. the ergl protein was successfully expressed and translated into an active form, demonstrated by ergl activity in the tuber extracts. ...200212028571
description of a cellulose-binding domain and a linker sequence from aspergillus fungi.a family i cellulose-binding domain (cbd) and a serine- and threonine-rich linker peptide were cloned from the fungi aspergillus japonicus and aspergillus aculeatus. a glutathione s-transferase (gst) fusion protein comprising gst and a peptide linker with the cbd fused to its c-terminus, was expressed in escherichia coli. the renatured gst-cbd recovered from inclusion bodies had a molecular mass of 36.5 kda which agrees with the 29 kda of the gst plus the calculated 7.5 kda of the linker with th ...200211956750
cj-15,183, a new inhibitor of squalene synthase produced by a fungus, aspergillus aculeatus.a new squalene synthase (ssase) inhibitor, cj-15,183 (i) was isolated from the fermentation broth of a fungus, aspergillus aculeatus cl38916. the compound potently inhibited rat liver and candida albicans microsomal ssases and also inhibited the human enzyme. it also showed antifungal activities against filamentous fungi and a yeast. the structure was determined to be an aliphatic tetracarboxylic acid compound consisting of an alkyl gamma-lactone, malic acid and isocitric acid moieties by spectr ...200111827032
production and characterization of extracellular and intracellular tannase from newly isolated aspergillus aculeatus dbf 9.a comparative study on the simultaneous production of extra and intracellular tannase was made from newly isolated fungal strain aspergillus aculeatus dbf 9. this strain produced five times more intracellular enzyme within 24 h in liquid culture than the extracellular form. maximum tannase production occurred in the culture broth containing 1-2% (w/v) tannic acid and 0.05-0.1% (w/v) glucose. the ph and temperature optima of both the enzymes were found at 5.0 and 50-60 degrees c, respectively. ex ...200111802541
a branched n-linked glycan at atomic resolution in the 1.12 a structure of rhamnogalacturonan acetylesterase.the crystal structure of the glycoprotein rhamnogalacturonan acetylesterase from aspergillus aculeatus has been refined to a resolution of 1.12 a using synchrotron data collected at 263 k. both of the two putative n-glycosylation sites at asn104 and asn182 are glycosylated and, owing to crystal contacts, the glycan structure at asn182 is exceptionally well defined in the electron-density maps, showing the six-carbohydrate structure manalpha1-6(manalpha1-3)manalpha1-6manbeta1-4glcnacbeta1-4glcnac ...200211752785
functional cloning of an endo-arabinanase from aspergillus aculeatus and its heterologous expression in a. or oryzae and tobacco.functional cloning in yeast has been used to isolate full-length cdnas encoding an endo-alpha-1,5-l-arabinanase from the filamentous fungus aspergillus aculeatus. screening of a cdna library constructed in a yeast expression vector for transformants that hydrolysed azcl-arabinan identified 44 saccharomyces cerevisiae clones all harbouring the same arabinanase-encoding cdna. the cloned cdna was expressed in a. oryzae and the recombinant enzyme was purified and characterized. the mode of action of ...200111523809
the x-ray structure of aspergillus aculeatus polygalacturonase and a modeled structure of the polygalacturonase-octagalacturonate complex.polygalacturonases hydrolyze the alpha-(1-4) glycosidic bonds of de-esterified pectate in the smooth region of the plant cell wall. crystal structures of polygalacturonase from aspergillus aculeatus were determined at ph 4.5 and 8.5 both to 2.0 a resolution. a. aculeatus polygalacturonase is a glycoprotein with one n and ten o-glycosylation sites and folds into a right-handed parallel beta-helix. the structures of the three independent molecules are essentially the same, showing no dependency on ...200111518536
purification and characterization of two different alpha-l-rhamnosidases, rhaa and rhab, from aspergillus aculeatus.two proteins exhibiting alpha-l-rhamnosidase activity, rhaa and rhab, were identified upon fractionation and purification of a culture filtrate from aspergillus aculeatus grown on hesperidin. both proteins were shown to be n glycosylated and had molecular masses of 92 and 85 kda, of which approximately 24 and 15%, respectively, were contributed by carbohydrate. rhaa and rhab, optimally active at ph 4.5 to 5, showed k(m) and v(max) values of 2.8 mm and 24 u/mg (rhaa) and 0.30 mm and 14 u/mg (rhab ...200111319105
in vitro evaluation of nonstarch polysaccharide digestibility of feed ingredients by enzymes.some of the commonly used feed ingredients for poultry (corn, sorghum, finger millet, deoiled ricebran, soybean meal, peanut meal, sunflower meal, and rapeseed meal) were screened for pentosans, cellulose, pectin, and total nonstarch polysaccharides. the ingredient in vitro digestibilities by enzymes were evaluated. cereal samples screened contained mainly pentosans. pectin content was rich in oilseed meals. sunflower meal, soybean meal, deoiled rice bran, and a broiler starter diet were subject ...200111261560
expression and action pattern of botryotinia fuckeliana (botrytis cinerea) rhamnogalacturonan hydrolase in pichia pastoris.the cdna sequence coding for the complete rhamnogalacturonan hydrolase (rgase) of botryotinia fuckeliana (botrytis cinerea) was introduced into pichia pastoris and expressed under the control of the alcohol oxidase promoter. the rgase was secreted into the medium of the yeast driven by the alpha-factor secretion peptide and could be purified using the c-terminal his6-tag fusion. rgase activity was measured using a traditional reducing end assay with linseed rhamnogalacturonan (rg) as the substra ...200111217965
expression of the aspergillus aculeatus endo-beta-1,4-mannanase encoding gene (man1) in saccharomyces cerevisiae and characterization of the recombinant enzyme.the endo-beta-1,4-mannanase encoding gene man1 of aspergillus aculeatus mrc11624 was amplified from mrna by polymerase chain reaction using sequence-specific primers designed from the published sequence of man1 from a. aculeatus ksm510. the amplified fragment was cloned and expressed in saccharomyces cerevisiae under the gene regulation of the alcohol dehydrogenase (adh2(pt)) and phosphoglycerate kinase (pgk1(pt)) promoters and terminators, respectively. the man1 gene product was designated man5 ...200111162394
combined molecular and biochemical approach identifies aspergillus japonicus and aspergillus aculeatus as two species.we examined nine aspergillus japonicus isolates and 10 aspergillus aculeatus isolates by using molecular and biochemical markers, including dna sequences of the its1-5.8s rrna gene-its2 region, restriction fragment length polymorphisms (rflp), and secondary-metabolite profiles. the dna sequence of the internal transcribed spacers (its1 and its2) and the 5.8s rrna gene could not be used to distinguish between a. japonicus and a. aculeatus but did show that these two taxa are more closely related ...200111157212
purification and characterisation of a beta-galactosidase from aspergillus aculeatus with activity towards (modified) exopolysaccharides from lactococcus lactis subsp. cremoris b39 and b891.beta-galactosidase from aspergillus aculeatus was purified from a commercial source for its hydrolytic activity towards (modified) exopolysaccharides (epss) produced by lactococcus lactis subsp. cremoris b39 and b891. the enzyme had a molecular mass of approximately 120 kda, a pi between 5.3 and 5.7 and was optimally active at ph 5.4 and 55-60 degrees c. based on the n-terminal amino acid sequence, the enzyme probably belongs to family 35 of the glycosyl hydrolases. the catalytic mechanism was s ...200011086688
rhamnogalacturonan acetylesterase elucidates the structure and function of a new family of hydrolases.the complex polysaccharide rhamnogalacturonan constitutes a major part of the hairy region of pectin. it can have different types of carbohydrate sidechains attached to the rhamnose residues in the backbone of alternating rhamnose and galacturonic acid residues; the galacturonic acid residues can be methylated or acetylated. aspergillus aculeatus produces enzymes that are able to perform a synergistic degradation of rhamnogalacturonan. the deacetylation of the backbone by rhamnogalacturonan acet ...200010801485
in vitro biosynthesis of 1,4-beta-galactan attached to rhamnogalacturonan i.the biosynthesis of galactan was investigated using microsomal membranes isolated from suspension-cultured cells of potato (solanum tuberosum l. var. azy). incubation of the microsomal membranes in the presence of udp-[14c]galactose resulted in a radioactive product insoluble in 70% methanol. the product released only [14c]galactose upon acid hydrolysis. treatment of the product with aspergillus niger endo-1,4-beta-galactanase released 65-70% of the radioactivity to a 70%-methanol-soluble fracti ...200010787056
structural characterisation and enzymic modification of the exopolysaccharide produced by lactococcus lactis subsp. cremoris b39.lactococcus lactis subsp. cremoris b39 grown on whey permeate produced an exopolysaccharide containing l-rha, d-gal and d-glc in a molar ratio of 2:3:2. the polysaccharide was modified using an enzyme preparation from aspergillus aculeatus, resulting in the release of gal and a polymer with approximately the same hydrodynamic volume as the native polysaccharide. linkage analysis and 1h nmr studies of both the native and modified exopolysaccharides elucidated that terminally linked gal was releas ...200010724531
analysis of a catalytic acidic pair in the active center of cellulase from aspergillus aculeatus.four acidic amino acid residues, asp97, asp101, glu118, and glu202, were located in the cleft from the x-ray crystallographic analysis of fi-cmcase, endo-1,4-beta-glucanase (ec: 3.2.1.4) of aspergillus aculeatus no. f-50. to identify the catalytic residues of the fi-cmcase, these residues were mutated to glu or ser from asp97 and asp101, and to asp or ser from glu118 and glu202 by site-directed mutagenesis, and totally 8 single mutant enzymes expressed in escherichia coli were prepared: d97e, d9 ...199910664848
the engl gene cluster of clostridium cellulovorans contains a gene for cellulosomal mana.a five-gene cluster around the gene in clostridium cellulovorans that encodes endoglucanase engl, which is involved in plant cell wall degradation, has been cloned and sequenced. as a result, a mannanase gene, mana, has been found downstream of engl. the mana gene consists of an open reading frame with 1,275 nucleotides encoding a protein with 425 amino acids and a molecular weight of 47, 156. mana has a signal peptide followed by a duplicated sequence (ds, or dockerin) at its n terminus and a c ...200010613891
hydrolytic properties of a beta-mannosidase purified from aspergillus niger.a beta-mannosidase was purified to homogeneity from the culture filtrate of aspergillus niger. a specific activity of 500 nkat mg-1 and a 53-fold purification was achieved using ammonium sulfate precipitation, anion-exchange chromatography, and gel filtration. the isolated enzyme has an isoelectric point of 5.0 and appears to be a dimer composed of two 135-kda subunits. it is a glycoprotein and contains 17% n-linked carbohydrate by weight. maximal activity was observed at ph 2.4 5.0 and at 70 de ...199910553664
safety evaluation of a fungal pectinesterase enzyme preparation and its use in food.the aspergillus aculeatus pectinesterase enzyme is used to modify the texture of plant derived products. it is produced by a. oryzae transformed with the cloned full length cdna of a. aculeatus encoding pectinesterase. it was subjected to a series of toxicological tests to document safety in use. the enzyme preparation was not found to be mutagenic in the ames test, and did not cause chromosomal damage in a human lymphocyte assay. in a 13-week oral-toxicity study in rats, with daily dosages up t ...199810209572
crystallization and preliminary x-ray studies of beta-1, 4-galactanase from aspergillus aculeatus.recombinant beta-1,4-galactanase from aspergillus aculeatus has been crystallized and characterized by x-ray diffraction. crystals were obtained in hanging drops by vapour-diffusion under the conditions 30% peg 400, 0.2 m cacl2 and 0.1 m na hepes buffered to ph 7.5. the crystals diffract to 2.3 a resolution and belong to one of the orthorhombic space groups i222 or i212121. the unit-cell dimensions are a = 60.42, b = 88.94 and c = 129.08 a. with one molecule in the asymmetric unit, the correspon ...199910089338
okaramines h and i, new okaramine congeners, from aspergillus aculeatustwo new congeners of okaramine, okaramines h (3) and i (4), were isolated from okara fermented with aspergillus aculeatus kf-428. their structures were elucidated by spectroscopic methods. neither okaramine h nor i showed insecticidal activity against silkworms.199910075772
cloning and sequencing of beta-mannosidase gene from aspergillus aculeatus no. f-50.the manb gene, coding for a unique beta-mannosidase (manb) of aspergillus aculeatus, was cloned from genomic and cdna libraries, and sequenced. the gene consists of 2,811 bp encoding a polypeptide of 937 amino acid residues with a molecular mass of 104,214 da. the a. aculeatus manb shared amino acid sequence identity with manb of human (24%), goat (24%), bovine (24%), and caenorhabditis elegans (22%). when the a. aculeatus manb was compared with other related enzymes, a glu residue corresponding ...199910052144
pectin methylesterase gene (pmea) from aspergillus oryzae kbn616: its sequence analysis and overexpression, and characterization of the gene product.a gene (pmea) encoding pectin methylesterase was isolated from a shoyu koji mold, aspergillus oryzae kbn616, and characterized. the structural gene comprised 1,370 bp with six introns. the pmea protein consisted of 331 amino acids with a putative signal peptide of 17 amino acids. the deduced amino acid sequence was very similar to those of aspergillus niger pmea and aspergillus aculeatus pme1. the pmea gene was efficiently expressed under control of the a. oryzae tef1 gene promoter for purificat ...199910052131
a xyloglucan-specific endo-beta-1,4-glucanase from aspergillus aculeatus: expression cloning in yeast, purification and characterization of the recombinant enzyme.a full-length c-dna encoding a xyloglucan-specific endo -beta-1, 4-glucanase (xeg) has been isolated from the filamentous fungus aspergillus aculeatus by expression cloning in yeast. the colonies expressing functional xeg were identified on agar plates containing azurine-dyed cross-linked xyloglucan. the cdna encoding xeg was isolated, sequenced, cloned into an aspergillus expression vector, and transformed into aspergillus oryzae for heterologous expression. the recombinant enzyme was purified ...19999884411
assimilation of cellooligosaccharides by a cell surface-engineered yeast expressing beta-glucosidase and carboxymethylcellulase from aspergillus aculeatussince saccharomyces cerevisiae lacks the cellulase complexes that hydrolyze cellulosic materials, which are abundant in the world, two types of hydrolytic enzymes involved in the degradation of cellulosic materials to glucose were genetically co-immobilized on its cell surface for direct utilization of cellulosic materials, one of the final goals of our studies. the genes encoding fi-carboxymethylcellulase (cmcase) and beta-glucosidase from the fungus aspergillus aculeatus were individually fuse ...19989835574
softwood hemicellulose-degrading enzymes from aspergillus niger: purification and properties of a beta-mannanase.the enzymes needed for galactomannan hydrolysis, i.e., beta-mannanase, alpha-galactosidase and beta-mannosidase, were produced by the filamentous fungus aspergillus niger. the beta-mannanase was purified to electrophoretic homogeneity in three steps using ammonium sulfate precipitation, anion-exchange chromatography and gel filtration. the purified enzyme had an isoelectric point of 3.7 and a molecular mass of 40 kda. ivory nut mannan was degraded mainly to mannobiose and mannotriose when incuba ...19989803534
expression of aspergillus aculeatus no. f-50 cellobiohydrolase i (cbhi) and beta-glucosidase 1 (bgl1) genes by saccharomyces cerevisiae.a cellobiohydrolase i (cbhi) and a beta-glucosidase 1 (bgl1) gene of aspergillus aculeatus were expressed in saccharomyces cerevisiae. the transformed cells secreted the enzymes efficiently in an active form. the recombinant cbhi gave two bands of different molecular mass (110 and 90 kda) and the recombinant bgl1 gave one band (180 kda) by sds-page. the recombinant cbhi and bgl1 had the same enzymatical properties as the native enzyme except for the specific activity toward cellulosic substrates ...19989757570
crystallization and preliminary x-ray diffraction studies of the heterogeneously glycosylated enzyme rhamnogalacturonan acetylesterase from aspergillus aculeatus.well diffracting crystals of rhamnogalacturonan acetylesterase from aspergillus aculeatus have been obtained in two polymorphic modifications despite its heterogeneous glycosylation. the best-diffracting crystals (resolution 1.55 a) are orthorhombic. the limit of the diffraction pattern of the other (trigonal) form is 2.5 a. the ability of the enzyme to crystallize appears to depend on the glycosylation of the protein sample. this aspect has been investigated by mass spectrometry, which also sho ...19989757128
crystal structure of polygalacturonase from erwinia carotovora ssp. carotovora.the crystal structure of the 40-kda endo-polygalacturonase from erwinia carotovora ssp. carotovora was solved by multiple isomorphous replacement and refined at 1.9 a to a conventional crystallographic r-factor of 0.198 and rfree of 0.239. this is the first structure of a polygalacturonase and comprises a 10 turn right-handed parallel beta-helix domain with two loop regions forming a "tunnel like" substrate-binding cleft. sequence conservation indicates that the active site of polygalacturonase ...19989733763
structure and evolution of parallel beta-helix proteins.three bacterial pectate lyases, a pectin lyase from aspergillus niger, the structures of rhamnogalacturonase a from aspergillus aculeatus, rgase a, and the p22-phage tailspike protein, tsp, display the right-handed parallel beta-helix architecture first seen in pectate lyase. the lyases have 7 complete coils while rgase a and tsp have 11 and 12, respectively. each coil contains three beta-strands and three turn regions named pb1, t1, pb2, t2, pb3, and t3 in their order of occurrence. the lyases ...19989724625
rhamnogalacturonan alpha-d-galactopyranosyluronohydrolase. an enzyme that specifically removes the terminal nonreducing galacturonosyl residue in rhamnogalacturonan regions of pectina new enzyme, rhamnogalacturonan (rg) alpha-d-galactopyranosyluronohydrolase (rg-galacturonohydrolase), able to release a galacturonic acid residue from the nonreducing end of rg chains but not from homogalacturonan, was purified from an aspergillus aculeatus enzyme preparation. rg-galacturonohydrolase acted with inversion of anomeric configuration, initially releasing beta-d-galactopyranosyluronic acid. the enzyme cleaved smaller rg substrates with the highest catalytic efficiency. a michaelis ...19989576784
characterization of recombinant rhamnogalacturonan alpha-l-rhamnopyranosyl-(1,4)-alpha-d-galactopyranosyluronide lyase from aspergillus aculeatus. an enzyme that fragments rhamnogalacturonan i regions of pectin.the four major oligomeric reaction products from saponified modified hairy regions (mhr-s) from apple, produced by recombinant rhamnogalacturonan (rg) alpha-l-rhamnopyranosyl-(1, 4)-alpha-d-galactopyranosyluronide lyase (rrg-lyase) from aspergillus aculeatus, were isolated and characterized by 1h-nuclear magnetic resonance spectroscopy. they contain an alternating rg backbone with a degree of polymerization of 4, 6, 8, and 10 and with an alpha-delta-(4,5)-unsaturated d-galactopyranosyluronic aci ...19989576783
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