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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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
complete saccharification of cellulose at high temperature using endocellulase and beta-glucosidase from pyrococcus sp.we investigated a potential for glucose production from cellulose material using two kinds of hyperthermophilic enzymes, endo-cellulase (eg) and beta-glucosidase (bgl). two bgls from hyperthermophile pyrococcus furiosus and mesophile aspergillus aculeatus were compared for complete hydrolysis of cellulose with p. horikoshii endo-cellulase (egph). the combination reactions by each bgl enzyme and egph could produce only glucose without the other oligosaccharides from phosphoric acid swollen avicel ...201020519912
hydrolysis of softwood by aspergillus mannanase: role of a carbohydrate-binding module.endo beta-1,4-mannanases (beta-mannanases, ec 3.2.1.78), belonging to cazy gh5 and gh26 families, catalyze the hydrolysis of structurally different mannans. in this study, the mannanase encoding gene of aspergillus aculeatus vn was expressed in aspergillus niger d15#26 using pan 52-4 vector, under the control of pgpda promoter and ttrpc terminator. in order to improve the hydrolytic capacity of this gh5 on lignocellulosic substrate, the family 1 carbohydrate-binding module (cbm1) of aspergillus ...201020541570
characterization of functional intermediates of endoglucanase from aspergillus aculeatus during urea and guanidine hydrochloride unfolding.low concentrations of urea and guhcl (2 m) enhanced the activity of endoglucanase (ec 3.1.2.4) from aspergillus aculeatus by 2.3- and 1.9-fold, respectively. the k(m) values for controls, in the presence of 2 m urea and guhcl, were found to be 2.4 +/- 0.2 x 10(-8) mol l(-1), 1.4 +/- 0.2 x 10(-8) mol l(-1), and 1.6 +/- 0.2 x 10(-8) mol l(-1), respectively. the dissociation constant (kd) showed changes in the affinity of the enzyme for the substrate with increases in the kcat suggesting an increas ...201020627273
involvement of tbl/duf231 proteins into cell wall biology.through map-based cloning we determined trichome birefringence (tbr) to belong to a plant-specific, yet anonymous gene family with 46 members in arabidopsis thaliana. these genes all encode the domain of unknown function 231 (duf231). tbr and its homolog trichome birefringence-like3 (tbl3) are transcriptionally coordinated with cellulose synthase (cesa) genes, and loss of tbr or tbl3 results in decreased levels of crystalline secondary wall cellulose in trichomes and stems, respectively. loss of ...201020657172
direct ethanol production from cellulosic materials at high temperature using the thermotolerant yeast kluyveromyces marxianus displaying cellulolytic enzymes.to exploit cellulosic materials for fuel ethanol production, a microorganism capable of high temperature and simultaneous saccharification-fermentation has been required. however, a major drawback is the optimum temperature for the saccharification and fermentation. most ethanol-fermenting microbes have an optimum temperature for ethanol fermentation ranging between 28 degrees c and 37 degrees c, while the activity of cellulolytic enzymes is highest at around 50 degrees c and significantly decre ...201020676628
noah's nectar: the proteome content of a glass of red wine.combinatorial peptide ligand libraries (cplls) have been adopted for harvesting and identifying traces of proteins present in red wines. surprisingly, although it is stated that red wines are in general fined with egg albumin, for all italian wines investigated (in the areas around chiari and verona as well as in the chianti area) we find that the only fining agent used is bovine casein, just like in white wines. although the typical levels of casein found range between 45 to 85μg/l, in one case ...201020813213
structural and biochemical studies elucidate the mechanism of rhamnogalacturonan lyase from aspergillus aculeatus.we present here the first experimental evidence for bound substrate in the active site of a rhamnogalacturonan lyase belonging to family 4 of polysaccharide lyases, aspergillus aculeatus rhamnogalacturonan lyase (rgl4). rgl4 is involved in the degradation of rhamnogalacturonan-i, an important pectic plant cell wall polysaccharide. based on the previously determined wild-type structure, enzyme variants rgl4_h210a and rgl4_k150a have been produced and characterized both kinetically and structurall ...201020851126
advantages of isothermal titration calorimetry for xylanase kinetics in comparison to chemical-reducing-end assays.in lignocellulosic raw materials for biomass conversion, hemicelluloses constitute a substantial fraction, with xylan being the primary part. although many pretreatments reduce the amount or change the distribution of xylan, it is important to degrade residual xylan so as to improve the overall yield. typically, xylanase reaction rates are measured in stopped assays by chemical quantification of the reducing ends. with isothermal titration calorimetry (itc), the heat flow of the hydrolysis can b ...201021074510
maximal release of highly bifidogenic soluble dietary fibers from industrial potato pulp by minimal enzymatic treatment.potato pulp is a poorly utilized, high-volume co-processing product resulting from industrial potato starch manufacturing. potato pulp mainly consists of the tuber plant cell wall material and is particularly rich in pectin, notably galactan branched rhamnogalacturonan i type pectin which has previously been shown to exhibit promising properties as dietary fiber. the objective of this study was to solubilize dietary fibers from potato pulp by a one-step minimal treatment procedure and evaluate t ...201121253720
glutamate production from ß-glucan using endoglucanase-secreting corynebacterium glutamicum.we demonstrate glutamate production from ß-glucan using endoglucanase (eg)-expressing corynebacterium glutamicum. the signal sequence tora derived from escherichia coli k12, which belongs to the tat pathway, was suitable for secreting eg of clostridium thermocellum using c. glutamicum as a host. using the tora signal sequence, endoglucanase from clostridium cellulovorans 743b was successfully expressed, and the secreted eg produced 123 mg of reducing sugar from 5 g of ß-glucan at 30 °c for 72 h, ...201121305281
aspergillus saccharolyticus sp. nov., a new black aspergillus species isolated in denmark.a novel species, aspergillus saccharolyticus sp. nov., is described within aspergillus section nigri species. this species was isolated in denmark from treated hardwood. its 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, and universally-primed pcr fingerprinting) characteristics. these features clearly distinguished this species from o ...201121335500
itaconic acid derivatives and diketopiperazine from the marine-derived fungus aspergillus aculeatus cri322-03.three metabolites, pre-aurantiamine (1), (-)-9-hydroxyhexylitaconic acid (4) and (-)-9-hydroxyhexylitaconic acid-4-methyl ester (5), together with two known compounds, paraherquamide e (6) and secalonic acid d (7), were isolated from the marine-derived fungus, aspergillus aculeatus.201121397285
characterization of galactooligosaccharides derived from lactulose.galactooligosaccharides are non-digestible carbohydrates with potential ability to modulate selectively the intestinal microbiota. in this work, a detailed characterization of oligosaccharides obtained by transgalactosylation reactions of the prebiotic lactulose, by using β-galactosidases of different fungal origin (aspergillus oryzae, aspergillus aculeatus and kluveromyces lactis), is reported. oligosaccharides of degree of polymerization (dp) up to 6 were detected and quantified by hplc-esi ms ...201121641605
influence of ethylenediaminetetraacetic acid (edta) on the structural stability of endoglucanase from aspergillus aculeatus.the effect of the chelating agent ethylenediaminetetraacetic acid (edta) on the structure and function of endoglucanase is studied. in the presence of 2 mm edta, endoglucanase showed an enhanced enzymatic activity of 1.5-fold compared to control. no further change in activity was observed with increase in the concentration of edta to 5 mm. the k(m) values for control and in the presence of edta are 0.060 and 0.044%, respectively, and k(cat) was 1.9 min(-1) in the presence of edta. the kinetic pa ...201121651310
asperaculin a, a sesquiterpenoid from a marine-derived fungus, aspergillus aculeatus.a novel sesquiterpenoid, asperaculin a, possessing a novel [5,5,5,6]fenestrane ring system, was isolated from the marine-derived fungus aspergillus aculeatus cri323-04. the structure of asperaculin a was established by analysis of spectroscopic data. the name aspergillane is proposed for the sesquiterpene skeleton in asperaculin a.201121667999
activity of three +¦-1,4-galactanases on small chromogenic substrates.+¦-1,4-galactanases belong to glycoside hydrolase family gh 53 and degrade galactan and arabinogalactan side chains of the complex pectin network in plant cell walls. two fungal +¦-1,4-galactanases from aspergillus aculeatus, meripileus giganteus and one bacterial enzyme from bacillus licheniformis have been kinetically characterized using the chromogenic substrate analog 4-nitrophenyl +¦-1,4-d-thiogalactobioside synthesized by the thioglycoligase approach. values of k(cat)/k(m) for this substra ...201121696710
direct ethanol production from hemicellulosic materials of rice straw by use of an engineered yeast strain codisplaying three types of hemicellulolytic enzymes on the surface of xylose-utilizing saccharomyces cerevisiae cells.the cost of the lignocellulose-hydrolyzing enzymes used in the saccharification process of ethanol production from biomass accounts for a relatively high proportion of total processing costs. cell surface engineering technology has facilitated a reduction in these costs by integrating saccharification and fermentation processes into a recombinant microbe strain expressing heterologous enzymes on the cell surface. we constructed a recombinant saccharomyces cerevisiae that not only hydrolyzed hemi ...201121741417
purification, crystallization and x-ray diffraction study of extracellular dermal glycoprotein from carrot and the inhibition complex that it forms with an endo-ß-glucanase from aspergillus aculeatus.extracellular dermal glycoprotein (edgp) may play an important role in the plant defence system of the carrot (daucus carota) as it has inhibitory activity against endo-ß-glucanase produced by invading pathogens. here, edgp and the inhibition complex that it forms with fi-cmcase, a carboxyl methyl cellulase from aspergillus aculeatus, were successfully crystallized. the hexagonal crystal of edgp belonged to space group p6(2), with unit-cell parameters a = b = 130.4, c = 44.5 å, ? = 120°. the mon ...201121795806
use of psychrophilic xylanases provides insight into the xylanase functionality in bread making.the bread improving potential of three psychrophilic xylanases from pseudoalteromonas haloplanktis tah3a (xph), flavobacterium sp. msy-2 (rxfh) and unknown bacterial origin (rxyn8) was compared to that of the mesophilic xylanases from bacillus subtilis (xbs) and aspergillus aculeatus (xaa). xph, rxfh and rxyn8 increased specific bread volumes up to 28%, 18% and 18%, respectively, while xbs and xaa gave increases of 23% and 12%, respectively. this could be related to their substrate hydrolysis be ...201121806059
construction of a recombinant trichoderma reesei strain expressing aspergillus aculeatus +¦-glucosidase 1 for efficient biomass conversion.to develop a trichoderma reesei strain appropriate for the saccharification of pretreated cellulosic biomass, a recombinant t. reesei strain, x3ab1, was constructed that expressed an aspergillus aculeatus +¦-glucosidase 1 with high specific activity under the control of the xyn3 promoter. the culture supernatant from t. reesei x3ab1 grown on 1% avicel as a carbon source had 63- and 25-fold higher +¦-glucosidase activity against cellobiose compared to that of the parent strain pc-3-7 and that of ...201121830204
Study of influential factors on oligosaccharide formation by fructosyltransferase activity during stachyose hydrolysis by Pectinex ultra SP-L.The influence of reaction conditions for oligosaccharide synthesis from stachyose using a commercial enzymatic preparation from Aspergillus aculeatus (Pectinex Ultra SP-L) was studied. Oligosaccharides were analyzed by gas chromatography with flame ionization detection (GC-FID) and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Galactosyl-melibiose (DP(3)) was synthesized as a result of fructosidase activity, whereas fructosyl-stachyose (DP(5)) and ...201121882802
acidic β-mannanase from penicillium pinophilum c1: cloning, characterization and assessment of its potential for animal feed application.the β-mannanase gene, man5c1, was cloned from penicillium pinophilum c1, a strain isolated from the acidic wastewater of a tin mine in yunnan, china, and expressed in pichia pastoris. the sequence analysis displayed the gene consists of a 1221-bp open reading frame encoding a protein of 406 amino acids (man5c1). the deduced amino acid sequence of man5c1 showed the highest homology of 57.8% (identity) with a characterized β-mannanase from aspergillus aculeatus belonging to glycoside hydrolase fam ...201122036533
definition and characterization of enzymes for maximal biocatalytic solubilization of prebiotic polysaccharides from potato pulp.potato pulp is a high-volume co-processing product resulting from industrial potato starch manufacturing. potato pulp is particularly rich in pectin, notably galactan branched rhamnogalacturonan i polysaccharides, which are highly bifidogenic when solubilized. the objective of the present study was to characterize and compare four homogalacturonan degrading enzymes capable of catalyzing the required solubilization of these pectinaceous polysaccharides from potato pulp in a 1 min reaction. an add ...201122112514
agrobacterium tumefaciens-mediated transformation of aspergillus aculeatus for insertional mutagenesis.abstract: agrobacterium tumefaciens-mediated transformation (amt) was applied to aspergillus aculeatus. transformants carrying the t-dna from a binary vector pbig2rhph2 were sufficiently mitotically stable to allow functional genomic analyses. the amt technique was optimized by altering the concentration of acetosyringone, the ratio and concentration of a. tumefaciens and a. aculeatus cells, the duration of co-cultivation, and the status of a. aculeatus cells when using conidia, protoplasts, o ...201122166586
a novel endo-1,4-β-mannanase from bispora antennata with good adaptation and stability over a broad ph range.an endo-β-1,4-mannanase encoding gene, man5, was cloned from bispora antennata cbs 126.38, which was isolated from a beech stump. the cdna of man5 consists of 1,299 base pairs and encodes a 432-amino-acid protein with a theoretical molecular mass of 46.6 kda. deduced man5 exhibited the highest amino acid sequence identity of 58% to a β-mannanase of glycoside hydrolase family 5 from aspergillus aculeatus. recombinant man5 was expressed in pichia pastoris and purified to electrophoretic homogeneit ...201222258646
a revised architecture of primary cell walls based on biomechanical changes induced by substrate-specific endoglucanases.xyloglucan is widely believed to function as a tether between cellulose microfibrils in the primary cell wall, limiting cell enlargement by restricting the ability of microfibrils to separate laterally. to test the biomechanical predictions of this "tethered network" model, we assessed the ability of cucumber (cucumis sativus) hypocotyl walls to undergo creep (long-term, irreversible extension) in response to three family-12 endo-β-1,4-glucanases that can specifically hydrolyze xyloglucan, cellu ...201222362871
xlnr-independent signaling pathway regulates both cellulase and xylanase genes in response to cellobiose in aspergillus aculeatus.the expression levels of the cellulase and xylanase genes between the host strain and an xlnr disruptant were compared by quantitative rt-pcr (qpcr) to identify the genes controlled by xlnr-independent signaling pathway. the cellulose induction of the fi-carboxymethyl cellulase (cmc1) and fib-xylanase (xynib) genes was controlled by xlnr; in contrast, the cellulose induction of the fiii-avicelase (cbhi), fii-carboxymethyl cellulase (cmc2), and fia-xylanase (xynia) genes was controlled by an xlnr ...201222371227
mass production of rubusoside using a novel stevioside-specific β-glucosidase from aspergillus aculeatus.rubusoside (r) is a natural sweetener and a solubilizing agent with antiangiogenic and antiallergic properties. however, currently, its production is quite expensive, and therefore, we have investigated nine commercially available glycosidases to optimize an economically viable r-production method. a stevioside (st)-specific β-glucosidase (ssgase) was selected and purified 7-fold from aspergillus aculeatus viscozyme l by a two-step column chromatography procedure. the 79 kda protein was stable f ...201222530920
optimisation of synergistic biomass-degrading enzyme systems for efficient rice straw hydrolysis using an experimental mixture design.synergistic enzyme system for the hydrolysis of alkali-pretreated rice straw was optimised based on the synergy of crude fungal enzyme extracts with a commercial cellulase (celluclast™). among 13 enzyme extracts, the enzyme preparation from aspergillus aculeatus bcc 199 exhibited the highest level of synergy with celluclast™. this synergy was based on the complementary cellulolytic and hemicellulolytic activities of the bcc 199 enzyme extract. a mixture design was used to optimise the ternary en ...201222728789
a novel transcriptional regulator, clbr, controls the cellobiose- and cellulose-responsive induction of cellulase and xylanase genes regulated by two distinct signaling pathways in aspergillus aculeatus.the cellobiose- and cellulose-responsive induction of the fiii-avicelase (cbhi), fii-carboxymethyl cellulase (cmc2), and fia-xylanase (xynia) genes is not regulated by xlnr in aspergillus aculeatus, which suggests that this fungus possesses an unknown cellulase gene-activating pathway. to identify the regulatory factors involved in this pathway, we constructed a random insertional mutagenesis library using agrobacterium tumefaciens-mediated transformation of a. aculeatus ncp2, which harbors a tr ...201322851016
identifying and characterizing the most significant β-glucosidase of the novel species aspergillus saccharolyticus.the newly discovered fungal species aspergillus saccharolyticus was found to produce a culture broth rich in β-glucosidase activity. in this present work, the main β-glucosidase of a. saccharolyticus responsible for the efficient hydrolytic activity was identified, isolated, and characterized. ion exchange chromatography was used to fractionate the culture broth, yielding fractions with high β-glucosidase activity and only 1 visible band on an sds-page gel. mass spectrometry analysis of this ban ...201222906186
validation and application of hplc-esi-ms/ms method for the quantification of rbbr decolorization, a model for highly toxic molecules, using several fungi strains.a novel analytical method using hplc-ms/ms operating in selected reaction monitoring (srm) for evaluation of fungi efficacy to decolorize remazol brilliant blue r (rbbr) dye solution was developed, validated and applied. the method shows high sensibility allowing the detection of 4.6 pm of rbbr. four fungal strains were tested in liquid medium, three strains of aspergillus (aspergillus aculeatus, aspergillus flavus and aspergillus fumigatus) and phanerochaete chrysosporium. all fungi were able t ...201222985849
cellulosic ethanol production by combination of cellulase-displaying yeast cells.as an effort to find suitable endoglucanases to generate cellulolytic yeast strains, two fungal endoglucanases, thermoascus aurantiacus egi and trichoderma reesei egii, and two bacterial endoglucanases, clostridium thermocellum cela and celd, were expressed on the yeast surface, and their surface expression levels, ph- and temperature-dependent enzyme activities, and substrate specificities were analyzed. t. aurantiacus egi showed similar patterns of ph- and temperature-dependent activities to t ...201223040393
construction of a novel selection system for endoglucanases exhibiting carbohydrate-binding modules optimized for biomass using yeast cell-surface engineering.to permit direct cellulose degradation and ethanol fermentation, saccharomyces cerevisiae by4741 (δsed1) codisplaying 3 cellulases (trichoderma reesei endoglucanase ii [eg], t. reesei cellobiohydrolase ii [cbh], and aspergillus aculeatus β-glucosidase i [bg]) was constructed by yeast cell-surface engineering. the eg used in this study consists of a family 1 carbohydrate-binding module (cbm) and a catalytic module. a comparison with family 1 cbms revealed conserved amino acid residues and flexibl ...201223092441
purification and characterization of a naringinase from aspergillus aculeatus jmudb058.a naringinase from aspergillus aculeatus jmudb058 was purified, identified, and characterized. this naringinase had a molecular mass (mw) of 348 kda and contained four subunits with mws of 100, 95, 84, and 69 kda. mass spectrometric analysis revealed that the three larger subunits were β-d-glucosidases and that the smallest subunit was an α-l-rhamnosidase. the naringinase and its α-l-rhamnosidase and β-d-glucosidase subunits all had optimal activities at approximately ph 4 and 50 °c, and they we ...201323289582
reversible impairment of the ku80 gene by a recyclable marker in aspergillus aculeatus.auxotrophic mutants of aspergillus can be isolated in the presence of counter-selective compounds, but the process is laborious. we developed a method to enable reversible impairment of the ku80 gene (aaku80) in the imperfect fungus aspergillus aculeatus. aaku80 was replaced with a selection marker, orotidine 5'-phosphate decarboxylase (pyrg), followed by excision of pyrg between direct repeats (dr) to yield the aaku80 deletion mutant (mr12). the gene-targeting efficiency at the ornithine carbam ...201323311774
cellulosic ethanol production using a yeast consortium displaying a minicellulosome and β-glucosidase.cellulosic biomass is considered as a promising alternative to fossil fuels, but its recalcitrant nature and high cost of cellulase are the major obstacles to utilize this material. consolidated bioprocessing (cbp), combining cellulase production, saccharification, and fermentation into one step, has been proposed as the most efficient way to reduce the production cost of cellulosic bioethanol. in this study, we developed a cellulolytic yeast consortium for cbp, based on the surface display of c ...201323383678
crystal structures of glycoside hydrolase family 3 β-glucosidase 1 from aspergillus aculeatus.gh3 (glycoside hydrolase family 3) bgls (β-glucosidases) from filamentous fungi have been widely and commercially used for the supplementation of cellulases. aabgl1 (aspergillus aculeatus bgl1) belongs to the gh3 and shows high activity towards cellooligosaccharides up to high degree of polymerization. in the present study we determined the crystal structure of aabgl1. in addition to the substrate-free structure, the structures of complexes with glucose and various inhibitors were determined. th ...201323537284
the characterisation of xyloglucanase inhibitors from humulus lupulus.phytopathogenic fungi secrete a powerful arsenal of enzymes that are potentially active against each polysaccharide component of the plant cell wall. to defend themselves, plants synthetise a variety of molecules that inhibit the activity of cell wall-degrading enzymes. xyloglucan-specific endoglucanase inhibitor proteins (xegips) act specifically against the members of fungal glycoside hydrolase family 12 (gh12 in the cazy database). in the present study, we describe the identification of three ...201323561301
the binding of zinc ions to emericella nidulans endo-β-1,4-galactanase is essential for crystal formation.a novel emericella nidulans endo-β-1,4-galactanase (engal) demonstrates a strong capacity to generate high levels of very potent prebiotic oligosaccharides from potato pulp, a by-product of the agricultural potato-starch industry. engal belongs to glycoside hydrolase family 53 and shows high (72.5%) sequence identity to an endo-β-1,4-galactanase from aspergillus aculeatus. diffraction data extending to 2.0 å resolution were collected from a crystal of engal grown from conditions containing 0.2 m ...201323908026
hydrolysis of various thai agricultural biomasses using the crude enzyme from aspergillus aculeatus iizuka fr60 isolated from soil.in this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (cmcase) and xylanase activities. from all isolates, the fungal isolate fr60, which was identified as aspergillus aculeatus iizuka, showed high activities in both cmcase and xylanase with 517 mu/mg protein and 550 mu/mg protein, respectively. the crude enzyme from a. aculeatus iizuka fr60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable ...201224031852
biodegradation of 1,2,3,4-tetrachlorodibenzo-p-dioxin in liquid broth by brown-rot fungi.dioxins are a class of extremely hazardous molecules that might pose a threat to the environment. this work evaluated the microbial degradation of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-tcdd), in liquid broth using three brown-rot fungi and one white-rot fungi as control. a fast and reliable extraction method with recoveries of over 98% together with a validated gc-ms method was developed, and applied to quantify 1,2,3,4-tcdd in liquid broth, mycelia and reaction flask, with detection limi ...201324080442
[identification and characterization of aspergillus aculeatus jmudb058 for naringinase production].a new naringinase-producing strain, jmudb058 was identified and characterized.201324195376
bioethanol production from the nutrient stress-induced microalga chlorella vulgaris by enzymatic hydrolysis and immobilized yeast fermentation.the microalga chlorella vulgaris is a potential feedstock for bioenergy due to its rapid growth, carbon dioxide fixation efficiency, and high accumulation of lipids and carbohydrates. in particular, the carbohydrates in microalgae make them a candidate for bioethanol feedstock. in this study, nutrient stress cultivation was employed to enhance the carbohydrate content of c. vulgaris. nitrogen limitation increased the carbohydrate content to 22.4% from the normal content of 16.0% on dry weight ba ...201424333701
efficient yeast cell-surface display of exo- and endo-cellulase using the sed1 anchoring region and its original promoter.the recombinant yeast strains displaying the heterologous cellulolytic enzymes on the cell surface using the glycosylphosphatidylinositol (gpi) anchoring system are considered promising biocatalysts for direct conversion of lignocellulosic materials to ethanol. however, the cellulolytic activities of the conventional cellulase-displaying yeast strains are insufficient for the hydrolysis of cellulose. in this study, we constructed novel gene cassettes for the efficient cellulose utilization by ce ...201424423072
fructooligosaccharides synthesis by highly stable immobilized β-fructofuranosidase from aspergillus aculeatus.the enzymatic synthesis of fructooligosaccharides (fos) was carried out using a partially purified β-fructofuranosidase from the commercial enzyme preparation viscozyme l. partial purification of β-fructofuranosidase from viscozyme l was done by batch adsorption using ion-exchange resin deae-sepharose, showing a 6-fold increase in specific activity. the biocatalyst was then covalently immobilized on glutaraldehyde-activated chitosan particles. thermal stability of the biocatalyst was evaluated a ...201424528719
application of endo-β-1,4,d-mannanase and cellulase for the release of mannooligosaccharides from steam-pretreated spent coffee ground.spent coffee ground (scg), a present waste stream from instant coffee production, represents a potential feedstock for mannooligosaccharides (mos) production. mos can be used in nutraceutical products for humans/animals or added to instant coffee, increasing process yield and improving product health properties. the scg was evaluated for mos production by steam pretreatment and enzymatic hydrolysis with a recombinant mannanase and a commercial cellulase cocktail (acremonium, bioshigen co. ltd, j ...201424557953
improving bgl1 gene expression in saccharomyces cerevisiae through meiosis in an isogenic triploid.introducing large numbers of target genes into the chromosome of saccharomyces cerevisiae via δ-sequence-mediated integration is a good strategy for exploring the effects of gene dosage on expression and secretion of heterologous proteins. the expression of exogenous genes might be further improved through meiosis in an isogenic triploid. here, a stable strain a-8 was screened from 35 sexual spore colonies obtained from an isogenic triploid integratively expressing bgl1 from aspergillus aculeatu ...201424563302
a new steroid with long cross-conjugation structure from the marine-derived fungus aspergillus aculeatus.a new steroid with a long cross-conjugation structure, 15a-hydroxy-(22e, 24r)-ergosta-3, 5, 8 (14), 22-tetraen-7-one (1), was isolated from the marine-derived fungus aspergillus aculeatus. its structure was established by the extensive spectroscopic analyses, and its cytotoxicities against p388, hl-60, and pc-3 cell lines were measured in vitro.201424783508
[biological conversion of stevioside to steviol by aspergillus aculeatus and the purification of rebaudioside a].the purpose of this research was to apply aspergillus aculeatus solid fermentation extracts to convert stevioside and rebaudioside c, followed by identifying and purifying the new conversion product.201424783855
expression and evaluation of enzymes required for the hydrolysis of galactomannan.the cost-effective production of bioethanol from lignocellulose requires the complete conversion of plant biomass, which contains up to 30 % mannan. to ensure utilisation of galactomannan during consolidated bioprocessing, heterologous production of mannan-degrading enzymes in fungal hosts was explored. the aspergillus aculeatus endo-β-mannanase (man1) and talaromyces emersonii α-galactosidase (agal) genes were expressed in saccharomyces cerevisiae y294, and the aspergillus niger β-mannosidase ( ...201424888762
production and characterization of multi-polysaccharide degrading enzymes from aspergillus aculeatus bcc199 for saccharification of agricultural residues.enzymatic hydrolysis of lignocellulosic biomass into fermentable sugars is a key step in the conversion of agricultural by-products to biofuels and value-added chemicals. utilization of a robust microorganism for on-site production of biomass-degrading enzymes has gained increasing interest as an economical approach for supplying enzymes to biorefinery processes. in this study, production of multi-polysaccharide-degrading enzymes from aspergillus aculeatus bcc199 by solid-state fermentation was ...201425001556
dereplication guided discovery of secondary metabolites of mixed biosynthetic origin from aspergillus aculeatus.investigation of the chemical profile of the industrially important black filamentous fungus aspergillus aculeatus by uhplc-dad-hrms and subsequent dereplication has led to the discovery of several novel compounds. isolation and extensive 1d and 2d nmr spectroscopic analyses allowed for structural elucidation of a dioxomorpholine, a unique okaramine, an aflavinine and three novel structures of mixed biosynthetic origin, which we have named aculenes a-c. moreover, known analogues of calbistrins, ...201425068785
development of a cellulolytic saccharomyces cerevisiae strain with enhanced cellobiohydrolase activity.consolidated bioprocessing (cbp) is a promising technology for lignocellulosic ethanol production, and the key is the engineering of a microorganism that can efficiently utilize cellulose. development of saccharomyces cerevisiae for cbp requires high level expression of cellulases, particularly cellobiohydrolases (cbh). in this study, to construct a cbp-enabling yeast with enhanced cbh activity, three cassettes containing constitutively expressed cbh-encoding genes (cbh1 from aspergillus aculeat ...201425164958
nickel oxide nanoparticles film produced by dead biomass of filamentous fungus.the synthesis of nickel oxide nanoparticles in film form using dead biomass of the filamentous fungus aspergillus aculeatus as reducing agent represents an environmentally friendly nanotechnological innovation. the optimal conditions and the capacity of dead biomass to uptake and produce nanoparticles were evaluated by analyzing the biosorption of nickel by the fungus. the structural characteristics of the film-forming nickel oxide nanoparticles were analyzed by scanning electron microscopy (sem ...201425228324
development of a gin11/frt-based multiple-gene integration technique affording inhibitor-tolerant, hemicellulolytic, xylose-utilizing abilities to industrial saccharomyces cerevisiae strains for ethanol production from undetoxified lignocellulosic hemicelluloses.bioethanol produced by the yeast saccharomyces cerevisiae is currently one of the most promising alternatives to conventional transport fuels. lignocellulosic hemicelluloses obtained after hydrothermal pretreatment are important feedstock for bioethanol production. however, hemicellulosic materials cannot be directly fermented by yeast: xylan backbone of hemicelluloses must first be hydrolyzed by heterologous hemicellulases to release xylose, and the yeast must then ferment xylose in the presenc ...201425306430
an in vitro antibacterial and antifungal effects of cadmium(ii) complexes of hexamethyltetraazacyclotetradecadiene and isomers of its saturated analogue.to evaluate the antibacterial and antifungal effects of cadmium(ii) complexes with hexamethyltetraazacyclotetradecadiene ligands.201425312179
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