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simultaneous saccharification and viscosity reduction of cassava pulp using a multi-component starch- and cell-wall degrading enzyme for bioethanol production.in this study, an efficient ethanol production process using simultaneous saccharification and viscosity reduction of raw cassava pulp with no prior high temperature pre-gelatinization/liquefaction step was developed using a crude starch- and cell wall-degrading enzyme preparation from aspergillus aculeatus bcc17849. proteomic analysis revealed that the enzyme comprised a complex mixture of endo- and exo-acting amylases, cellulases, xylanases, and pectina ses belonging to various glycosyl hydrol ...201728868217
characterization of mechanisms underlying degradation of sclerotia of sclerotinia sclerotiorum by aspergillus aculeatus asp-4 using a combined qrt-pcr and proteomic approach.the biological control agent aspergillus aculeatus asp-4 colonizes and degrades sclerotia of sclerotinia sclerotiorum resulting in reduced germination and disease caused by this important plant pathogen. molecular mechanisms of mycoparasites underlying colonization, degradation, and reduction of germination of sclerotia of this and other important plant pathogens remain poorly understood.201728859614
does osmotic stress affect natural product expression in fungi?the discovery of new natural products from fungi isolated from the marine environment has increased dramatically over the last few decades, leading to the identification of over 1000 new metabolites. however, most of the reported marine-derived species appear to be terrestrial in origin yet at the same time, facultatively halo- or osmotolerant. an unanswered question regarding the apparent chemical productivity of marine-derived fungi is whether the common practice of fermenting strains in seawa ...201728805714
metabolomic tools to assess the chemistry and bioactivity of endophytic aspergillus strain.endophytic fungi associated with medicinal plants are a potential source of novel chemistry and biology that may find applications as pharmaceutical and agrochemical drugs. in this study, a combination of metabolomics and bioactivity-guided approaches were employed to isolate anticancer secondary metabolites from an endophytic aspergillus aculeatus. the endophyte was isolated from the egyptian medicinal plant terminalia laxiflora and identified using molecular biological methods. metabolomics an ...201728672096
dipeptidyl peptidase iv is involved in the cellulose-responsive induction of cellulose biomass-degrading enzyme genes in aspergillus aculeatus.we screened for factors involved in the cellulose-responsive induction of cellulose biomass-degrading enzyme genes from approximately 12,000 aspergillus aculeatus t-dna insertion mutants harboring a transcriptional fusion between the fiii-avicelase gene (cbhi) promoter and the orotidine 5'-monophosphate decarboxylase gene. analysis of 5-fluoroorodic acid (5-foa) sensitivity, cellulose utilization, and cbhi expression of the mutants revealed that a mutant harboring t-dna at the dipeptidyl peptida ...201728290772
effects of cadmium-resistant fungi aspergillus aculeatus on metabolic profiles of bermudagrass [cynodondactylon (l.)pers.] under cd stress.plants' tolerance to heavy metal stress may be induced by the exploitation of microbes. the objectives of this study were to investigate the effect of cadmium (cd)-resistant fungus, aspergillus aculeatus, on tolerance to cd and alteration of metabolites in bermudagrass under cd stress, and identify the predominant metabolites associated with cd tolerance. two genotypes of bermudagrass with contrasting cd tolerance (cd-sensitive 'wb92' and cd-tolerant 'wb242') were exposed to 0, 50, 150 and 250 m ...201728273510
secalonic acid- f inhibited cell growth more effectively than 5-fluorouracil on hepatocellular carcinoma in vitro and in vivo.hepatocellular carcinoma (hcc), one of the most common types of liver cancer, could be treated with 5-fluorouracil (5-fu). due to its side effects, 5-fu is more often used as the co-administration drug in clinical practice. secalonic acid-f (saf), isolated from a fungal strain identified in our lab as aspergillus aculeatus, showed potent biological activities. the goal of this study was to evaluate the inhibitory effects of saf on hepatocellular carcinoma and to compare it with that of 5-fu. res ...201728253713
heterologous expression of aspergillus aculeatus endo-polygalacturonase in pichia pastoris by high cell density fermentation and its application in textile scouring.removal of non-cellulosic impurities from cotton fabric, known as scouring, by conventional alkaline treatment causes environmental problems and reduces physical strength of fabrics. in this study, an endo-polygalacturonase (endopg) from aspergillus aculeatus produced in pichia pastoris was evaluated for its efficiency as a bioscouring agent while most current bioscouring process has been performed using crude pectinase preparation.201728209146
amelioration of salt stress on bermudagrass by the fungus aspergillus aculeatus.there is considerable evidence that plant abiotic-stress tolerance can be evoked by the exploitation of a globally abundant microbe. a. aculeatus, which was initially isolated from the rhizosphere of bermudagrass, has been shown to increase heavy metal tolerance in turfgrasses. here, we report on the potential of a. aculeatus to induce tolerance to salt stress in bermudagrass. physiological markers for salt stress, such as plant growth rate, lipid peroxidation, photosynthesis, and ionic homeosta ...201728134574
production of high galacto-oligosaccharides by pectinex ultra sp-l: optimization of reaction conditions and immobilization on glyoxyl-functionalized silica.a rational optimization for the synthesis of galacto-oligosaccharides (gos) from lactose catalyzed by β-galactosidase from aspergillus aculeatus, included in the commercial product pectinex ultra sp-l, has been performed by using experimental design and surface response methodology. this accurate tool optimized empirical production of the most desired high-gos (tri-gos and tetra-gos) up to 16.4% under the following reaction conditions: 59 °c, 4 u/ml free enzyme concentration, ph 6.5, 250 g/l ini ...201728176525
identification and functional characterization of a fructooligosaccharides-forming enzyme from aspergillus aculeatus.although fructosyltransferases from aspergillus aculeatus have received a considerable interest for the prebiotics industry, their amino acid sequences and structural features remain unknown. this study sequenced and characterized a fructosyltransferase from a. aculeatus (acft) isolated by heat treatment of pectinex ultra sp-l. the acft enzyme showed two isoforms, low-glycosylated acft1 and high-glycosylated acft2 forms, with similar optimum activity at 60 °c. the purified heat-resistant acft1 a ...201626857855
structure and antitumor activity of the extracellular polysaccharides from aspergillus aculeatus via apoptosis and cell cycle arrest.two extracellular polysaccharides, designated as wpa and wpb, were isolated from the fungus aspergillus aculeatus using q-sepharose fast flow and sephacryl s-300 column chromatography. wpa composed of mannose and galactose in a molar ratio of 3.9:1.0, and wpb mainly contained mannose. the molecular weight of wpa and wpb was about 28.1 kda and 21.0 kda, respectively. on the basis of methylation and nmr analysis, the possible main chain of wpa was [→5)-β-d-galf-(1 → 2,6)-α-d-manp(1→], and wpb was ...201627557923
crystal structure and genetic modifications of fi-cmcase from aspergillus aculeatus f-50.cellulose is the major component of the plant cell wall and the most abundant renewable biomass on earth, and its decomposition has proven to be very useful in many commercial applications. endo-1,4-β-d-glucanase (ec 3.2.1.4; endoglucanase), which catalyzes the random hydrolysis of 1,4-β-glycosidic bonds of the cellulose main chain to cleave cellulose into smaller fragments, is the key cellulolytic enzyme. an endoglucanase isolated from aspergillus aculeatus f-50 (fi-cmcase), which is classified ...201627470581
site-saturation mutagenesis for β-glucosidase 1 from aspergillus aculeatus to accelerate the saccharification of alkaline-pretreated bagasse.aspergillus aculeatus β-glucosidase 1 (aabgl1) is one of the best cellobiose hydrolytic enzymes without transglycosylation products, among β-glucosidase from various origins, for use in cellulosic biomass conversion with trichoderma cellulases. however, in our previous report, it was demonstrated that aabgl1 has lower catalytic efficiency toward cellobiose, which is a major end product from cellulosic biomasses by trichoderma reesei cellulases, than do gentiobiose and laminaribiose. thus, we exp ...201627444432
optimization of process parameters for enhanced production of jamun juice using pectinase (aspergillus aculeatus) enzyme and its characterization.jamun fruit comprises of seed and thick pulp. the pectin-protein bond of the thick pulp creates difficulty in making juice. clear jamun juice is not available in the market, so there is a need for extraction of juice with maximum yield. the goal of this research is to obtain high yield of clarified juice with the help of pectinase (aspergillus aculeatus) enzyme. the study was conducted at different enzyme concentration (0.01-0.1%), time duration (40-120 min), and temperature (30-50 °c). various ...201628330313
a high performance trichoderma reesei strain that reveals the importance of xylanase iii in cellulosic biomass conversion.the ability of the trichoderma reesei x3ab1strain enzyme preparations to convert cellulosic biomass into fermentable sugars is enhanced by the replacement of xyn3 by aspergillus aculeatus β-glucosidase 1 gene (aabg1), as shown in our previous study. however, subsequent experiments using t. reesei extracts supplemented with the glycoside hydrolase (gh) family 10 xylanase iii (xyn iii) and gh family 11 xyn ii showed increased conversion of alkaline treated cellulosic biomass, which is rich in xyla ...201626672453
highly efficient synthesis of fructooligosaccharides by extracellular fructooligosaccharide-producing enzymes and immobilized cells of aspergillus aculeatus m105 and purification and biochemical characterization of a fructosyltransferase from the fungus.in this work, aspergillus aculeatus m105 was obtained to produce high extracellular fructooligosaccharide-producing enzyme activity. the maximum yields of fructooligosaccharides produced by its extracellular enzymes and immobilized cells were 67.54 and 65.47% (w/w), respectively. a fructosyltransferase (ftase), aaft32a, was purified from m105. the optimal ph and temperature of aaft32a were ph 5.0-6.0 and 65 °c, respectively. the km, vmax, and kcat values for the transfructosylating activity of a ...201627492129
soybean bio-refinery platform: enzymatic process for production of soy protein concentrate, soy protein isolate and fermentable sugar syrup.soybean carbohydrate is often found to limit the use of protein in soy flour as food and animal feed due to its indigestibility to monogastric animal. in the current study, an enzymatic process was developed to produce not only soy protein concentrate and soy protein isolate without indigestible carbohydrate but also soluble reducing sugar as potential fermentation feedstock. for increasing protein content in the product and maximizing protein recovery, the process was optimized to include the f ...201627207010
towards complete hydrolysis of soy flour carbohydrates by enzyme mixtures for protein enrichment: a modeling approach.soy protein is a well-known nutritional supplement in proteinaceous food and animal feed. however, soybeans contain complex carbohydrate. selective carbohydrate removal by enzymes could increase the protein content and remove the indigestibility of soy products for inclusion in animal feed. complete hydrolysis of soy flour carbohydrates is challenging due to the presence of proteins and different types of non-structural polysaccharides. this study is designed to guide complex enzyme mixture requ ...201626992789
identification and characterization of an acidic and acid-stable endoxyloglucanase from penicillium oxalicum.xyloglucan is a major structural macromolecule of the primary cell wall of spermatophytes. the hydrolysis of xyloglucan by xyloglucanases may facilitate the hydrolysis of cellulose by cellulases, which is beneficial for bioethanol production. penicillium oxalicum has been employed for commercial cellulase production. in p. oxalicum, many genes and proteins related to the degradation of structural macromolecules of the plant cell wall have been found, but no gene encoding a xyloglucanase has been ...201626840178
heterologous expression of aspergillus terreus fructosyltransferase in kluyveromyces lactis.fructo-oligosaccharides are prebiotic and hypocaloric sweeteners that are usually extracted from chicory. they can also be produced from sucrose using fructosyltransferases, but the only commercial enzyme suitable for this purpose is pectinex ultra, which is produced with aspergillus aculeatus. here we used the yeast kluyveromyces lactis to express a secreted recombinant fructosyltransferase from the inulin-producing fungus aspergillus terreus. a synthetic codon-optimised version of the putative ...201627084521
rhamnogalacturonan i modifying enzymes: an update.rhamnogalacturonan i (rgi) modifying enzymes catalyse the degradation of the rgi backbone and encompass enzymes specific for either the α1,2-bond linking galacturonic acid to rhamnose or the α1,4-bond linking rhamnose to galacturonic acid in the rgi backbone. the first microbial enzyme found to be able to catalyse the degradation of the rgi backbone, an endo-hydrolase (ec 3.2.1.171) derived from aspergillus aculeatus, was discovered 25 years ago. today the group of rgi modifying enzymes encompas ...201626255130
screening and identification of novel ochratoxin a-producing fungi from grapes.ochratoxin a (ota) contamination has been established as a world-wide problem. in this study, the strains with the ability of ota production were screened by analyzing the green fluorescence of the isolates colonies from the grapes in zhenjiang with 365 nm uv light and confirmed by hplc with fluorescent detection (hplc-fld). the results showed that seven isolates acquired the characteristic of the fluorescence, of which only five showed the ability of ota production as confirmed by hplc-fld anal ...201627845758
enhanced cell-surface display and secretory production of cellulolytic enzymes with saccharomyces cerevisiae sed1 signal peptide.recombinant yeast strains displaying aheterologous cellulolytic enzymes on their cell surfaces using a glycosylphosphatidylinositol (gpi) anchoring system are a promising strategy for bioethanol production from lignocellulosic materials. a crucial step for cell wall localization of the enzymes is the intracellular transport of proteins in yeast cells. therefore, the addition of a highly efficient secretion signal sequence is important to increase the amount of the enzymes on the yeast cell surfa ...201627183011
direct ethanol fermentation of the algal storage polysaccharide laminarin with an optimized combination of engineered yeasts.laminarin is the algal storage glucan and represents up to 35% of the dry weight of brown macroalgae. in this study, a novel laminarinase, gly5m, was first found using focused proteome analysis of a laminarin-assimilating marine bacterium, saccharophagus degradans, and the encoding gene was isolated. a gly5m-displaying yeast strain was prepared with the cell surface display system using saccharomyces cerevisiae. it showed a laminarin-degrading activity on the cell surface and caused the dominant ...201627287535
heterologously expressed aspergillus aculeatus β-glucosidase in saccharomyces cerevisiae is a cost-effective alternative to commercial supplementation of β-glucosidase in industrial ethanol production using trichoderma reesei cellulases.trichoderma reesei is a filamentous organism that secretes enzymes capable of degrading cellulose to cellobiose. the culture supernatant of t. reesei, however, lacks sufficient activity to convert cellobiose to glucose using β-glucosidase (bgl1). in this study, we identified a bgl (cel3b) from t. reesei (trcel3b) and compared it with the active β-glucosidases from aspergillus aculeatus (aabgl1). aabgl1 showed higher stability and conversion of sugars to ethanol compared to trcel3b, and therefore ...201626073313
imaging of bacterial and fungal cells using fluorescent carbon dots prepared from carica papaya juice.in this paper, we have described a simple hydrothermal method for preparation of fluorescent carbon dots (c-dots) using carica papaya juice as a precursor. the synthesized c-dots show emission peak at 461 nm with a quantum yield of 7.0 %. the biocompatible nature of c-dots was confirmed by a cytotoxicity assay on e. coli. the c-dots were used as fluorescent probes for imaging of bacterial (bacillus subtilis) and fungal (aspergillus aculeatus) cells and emitted green and red colors under differen ...201526123674
biochemical characterization and overexpression of an endo-rhamnogalacturonan lyase from penicillium chrysogenum.rhamnogalacturonan lyase (pcrgl4a) was purified from the culture supernatant of penicillium chrysogenum 31b. pcrgl4a optimal activity occurred between ph 7-8 and at 40 °c. conserved domain search analysis identified pcrgl4a as a member of polysaccharide lyase family 4. pcrgl4a contains two conserved catalytic and four conserved substrate-binding residues as determined by x-ray crystallography of the aspergillus aculeatus rg lyase. recombinant pcrgl4a (rpcrgl4a) expressed in escherichia coli demo ...201525666014
co-expression of endoxylanase and endoglucanase in scheffersomyces stipitis and its application in ethanol production.scheffersomyces stipitis strain bcc15191 is considered as a biotechnologically valuable yeast for its ability to ferment glucose and xylose, the main sugar components in plant biomass, to ethanol. however, the wild strain lacks of endogenous cellulases and hemicellulases that limited biomass utilization. in order to improve biomass degrading ability of s. stipitis bcc15191, new integrative plasmids harboring constitutive tef1 promoter and codon-optimized zeocin or hygromycin antibiotic resistanc ...201526378014
cloning and genomic organization of a rhamnogalacturonase gene from locally isolated strain of aspergillus niger.the rhg gene encoding a rhamnogalacturonase was isolated from the novel strain a1 of aspergillus niger. it consists of an orf of 1.505 kb encoding a putative protein of 446 amino acids with a predicted molecular mass of 47 kda, belonging to the family 28 of glycosyl hydrolases. the nature and position of amino acids comprising the active site as well as the three-dimensional structure were well conserved between the a. niger ctm10548 and fungal rhamnogalacturonases. the coding region of the rhg ...201526142900
effect of mutations on the thermostability of aspergillus aculeatus β-1,4-galactanase.new variants of β-1,4-galactanase from the mesophilic organism aspergillus aculeatus were designed using the structure of β-1,4-galactanase from the thermophile organism myceliophthora thermophila as a template. some of the variants were generated using propka 3.0, a validated pka prediction tool, to test its usefulness as an enzyme design tool. the propka designed variants were d182n and s185d/q188t, g104d/a156r. variants y295f and g306a were designed by a consensus approach, as a complementary ...201525941560
synergistic action of recombinant accessory hemicellulolytic and pectinolytic enzymes to trichoderma reesei cellulase on rice straw degradation.synergism between core cellulases and accessory hydrolytic/non-hydrolytic enzymes is the basis of efficient hydrolysis of lignocelluloses. in this study, the synergistic action of three recombinant accessory enzymes, namely gh62 α-l-arabinofuranosidase (ara), ce8 pectin esterase (pet), and gh10 endo-1,4-beta-xylanase (xyl) from aspergillus aculeatus expressed in pichia pastoris to a commercial trichoderma reesei cellulase (accellerase® 1500; acr) on hydrolysis of alkaline pretreated rice straw w ...201526433794
a crispr-cas9 system for genetic engineering of filamentous fungi.the number of fully sequenced fungal genomes is rapidly increasing. since genetic tools are poorly developed for most filamentous fungi, it is currently difficult to employ genetic engineering for understanding the biology of these fungi and to fully exploit them industrially. for that reason there is a demand for developing versatile methods that can be used to genetically manipulate non-model filamentous fungi. to facilitate this, we have developed a crispr-cas9 based system adapted for use in ...201526177455
crystallization and preliminary x-ray diffraction analysis of an endo-1,4-β-d-glucanase from aspergillus aculeatus f-50.cellulose is the most abundant renewable biomass on earth, and its decomposition has proven to be very useful in a wide variety of industries. endo-1,4-β-d-glucanase (ec 3.2.1.4; endoglucanase), which can catalyze the random hydrolysis of β-1,4-glycosidic bonds to cleave cellulose into smaller fragments, is a key cellulolytic enzyme. an endoglucanase isolated from aspergillus aculeatus f-50 (fi-cmcase) that was classified into glycoside hydrolase family 12 has been found to be effectively expres ...201525849498
utilization of recombinant trichoderma reesei expressing aspergillus aculeatus β-glucosidase i (jn11) for a more economical production of ethanol from lignocellulosic biomass.the capacity of trichoderma reesei cellulase to degrade lignocellulosic biomass has been enhanced by the construction of a recombinant t. reesei strain expressing aspergillus aculeatus β-glucosidase i. we have confirmed highly efficient ethanol production from converge-milled japanese cedar by recombinant t. reesei expressing a. aculeatus β-glucosidase i (jn11). we investigated the ethanol productivity of jn11 and compared it with the cocktail enzyme t. reesei pc-3-7 with reinforced cellobiase a ...201526026380
investigation of a 6-msa synthase gene cluster in aspergillus aculeatus reveals 6-msa-derived aculinic acid, aculins a-b and epi-aculin a.aspergillus aculeatus, a filamentous fungus belonging to the aspergillus clade nigri, is an industrial workhorse in enzyme production. recently we reported a number of secondary metabolites from this fungus; however, its genetic potential for the production of secondary metabolites is vast. in this study we identified a 6-methylsalicylic acid (6-msa) synthase from a. aculeatus, and verified its functionality by episomal expression in a. aculeatus and heterologous expression in a. nidulans. feedi ...201526374386
characterization of aspergillus aculeatus β-glucosidase 1 accelerating cellulose hydrolysis with trichoderma cellulase system.aspergillus aculeatus β-glucosidase 1 (aabgl1), which promotes cellulose hydrolysis by trichoderma cellulase system, was characterized and compared some properties to a commercially supplied orthologue in a. niger (anbgl) to elucidate advantages of recombinant aabgl1 (raabgl1) for synergistic effect on trichoderma enzymes. steady-state kinetic studies revealed that raabgl1 showed high catalytic efficiency towards β-linked glucooligosaccharides. up to a degree of polymerization (dp) 3, raabgl1 pr ...201525642400
effects of clbr overexpression on enzyme production in aspergillus aculeatus vary depending on the cellulosic biomass-degrading enzyme species.clbr is a zn(ii)2cys6 transcriptional activator that controls the expression of cellulase-related genes in response to avicel and cellobiose in aspergillus aculeatus. a clbr-overexpressing strain (clbr-oe) that expresses the clbr gene at levels sevenfold higher than the control strain sustainably produced xylanolytic and cellulolytic activities during 10-day cultivation of a. aculeatus, enabling synchronization of xylanolytic and cellulolytic activities at a maximum level. however, clbr overexpr ...201525410617
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
[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
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
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
dietary sugars analysis: quantification of fructooligossacharides during fermentation by hplc-ri method.in this work, a simple chromatographic method is proposed and in-house validated for the quantification of total and individual fructooligossacharides (e.g., 1-kestose, nystose, and 1(f)-fructofuranosylnystose). it was shown that a high-performance liquid chromatography with refractive index detector could be used to monitor the dynamic of fructooligossacharides production via sucrose fermentation using aspergillus aculeatus. this analytical technique may be easily implemented at laboratorial or ...201425988114
identification of cadmium-resistant fungi related to cd transportation in bermudagrass [cynodon dactylon (l.) pers].phytoremediation utilizing plants and microbes has been increasingly adopted as a green technology for cleaning up heavy metal polluted soils. cd polluted soil and native bermudagrass from liuyang and zhuzhou in hunan province of china were collected to investigate microbial diversity and isolate cd resistant fungi, and then to determine the effect of cd resistant fungi on cd tolerance and transportation of bermudagrass. the functional diversity of microorganisms was evaluated using the biolog e ...201425461949
asperaculanes a and b, two sesquiterpenoids from the fungus aspergillus aculeatus.six sesquiterpenoids 1-6, including two new ones, an ent-daucane-type sesquiterpenoid, asperaculane a (1), and a nordaucane one, asperaculane b (2), and four known nordaucane derivatives, aculenes a-d 3-6, together with the known secalonic acid d (7), were isolated from a fermentation culture of the fungus aspergillus aculeatus. their structures and absolute configurations were established by analyses of their spectroscopic data, including 1d and 2d-nmr spectra, hr-esims, electronic circular dic ...201425547729
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
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
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
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
[display cellulolytic enzymes on saccharomyces cerevisiae cell surface by using flo1p as an anchor protein for cellulosic ethanol production].in this study, we constructed a yeast consortium surface-display expression system by using flo1 as an anchor protein. endoglucanase ii (egii) and cellobiohydrolase ii (cbhii) from trichoderma reesei, and β3-glucosidase 1 (bgli) from aspergillus aculeatus were immobilized on saccharomyces cerevisiae y5. we constructed the cellulose-displaying expression yeast consortium (y5/fegii:y5/fcbhii:y5/fbgli = 1:1:1) and investigated the enzymatic ability and ethanol fermentation. the displayed cellulolyt ...201425720155
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
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
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
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
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
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
[identification and characterization of aspergillus aculeatus jmudb058 for naringinase production].a new naringinase-producing strain, jmudb058 was identified and characterized.201324195376
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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