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Sample records for chaetomium thermophilum xylanase

  1. Cloning and expression of chaetomium thermophilum xylanase 11-A

    International Nuclear Information System (INIS)

    The various thermophilic fungi like Chaetomium thermophile has potential to secrete xylanase and cellulase enzymes. In the present study eukaryotic expression system of Pichia pastoris (yeast) was used to express xylanase gene. The xylanase (Xyn 11-A) gene was isolated from C. thermophile strain NIBGE-1. Primers were designed to amplify the gene, ligated into P. pastoris pPIC3.5K vector, the resultant recombinant clone pSSZ810 was transformed into the genome of P. pastoris GS115 strain through electroporation. Transformants were selected on yeast peptone dextrose medium (YPD) plates containing antibiotic geneticin (100 mg/ml) upto final concentration of 0.75 mg/ml. The maximum activity of xylanase 2.04 U/ml after incubation of 2 hours at 50 degree C was observed in the presence of 100% methanol inducer upto final concentration of 30 macro L (0.5%) as compared to control. HPLC analysis represented high peak of xylose as compared to control. SDS-PAGE indicated approx. 28 kDa protein of expressed xylanase gene. (author)

  2. An integrated approach for genome annotation of the eukaryotic thermophile Chaetomium thermophilum.

    Science.gov (United States)

    Bock, Thomas; Chen, Wei-Hua; Ori, Alessandro; Malik, Nayab; Silva-Martin, Noella; Huerta-Cepas, Jaime; Powell, Sean T; Kastritis, Panagiotis L; Smyshlyaev, Georgy; Vonkova, Ivana; Kirkpatrick, Joanna; Doerks, Tobias; Nesme, Leo; Baßler, Jochen; Kos, Martin; Hurt, Ed; Carlomagno, Teresa; Gavin, Anne-Claude; Barabas, Orsolya; Müller, Christoph W; van Noort, Vera; Beck, Martin; Bork, Peer

    2014-12-16

    The thermophilic fungus Chaetomium thermophilum holds great promise for structural biology. To increase the efficiency of its biochemical and structural characterization and to explore its thermophilic properties beyond those of individual proteins, we obtained transcriptomics and proteomics data, and integrated them with computational annotation methods and a multitude of biochemical experiments conducted by the structural biology community. We considerably improved the genome annotation of Chaetomium thermophilum and characterized the transcripts and expression of thousands of genes. We furthermore show that the composition and structure of the expressed proteome of Chaetomium thermophilum is similar to its mesophilic relatives. Data were deposited in a publicly available repository and provide a rich source to the structural biology community. PMID:25398899

  3. Accumulation of trehalose in the thermophilic fungus Chaetomium thermophilum var. coprophilum in response to heat or salt stress

    DEFF Research Database (Denmark)

    Jepsen, Helene Friborg; Jensen, B.

    2004-01-01

    The disaccharide trehalose, known to be an effective protectant against various kinds of stress, was observed to accumulate in the cytosol of Chaetomium thermophilum var. coprophilum during heat stress. Trehalose was apparently neither involved in the defence of C. thermophilum var. coprophilum...

  4. Hydrolysis of Wheat Arabinoxylan by Two Acetyl Xylan Esterases from Chaetomium thermophilum

    DEFF Research Database (Denmark)

    Tong, Xiaoxue; Lange, Lene; Grell, Morten Nedergaard;

    2015-01-01

    The thermophilic filamentous ascomycete Chaetomium thermophilum produces functionally diverse hemicellulases when grown on hemicellulose as carbon source. Acetyl xylan esterase (EC 3.1.1.72) is an important accessory enzyme in hemicellulose biodegradation. Although the genome of C. thermophilum has...... been sequenced, its carbohydrate esterases are not annotated yet. We applied peptide pattern recognition (PPR) tool for sequence analysis of the C. thermophilum genome, and 11 carbohydrate esterase genes were discovered. Furthermore, we cloned and heterologously expressed two putative acetyl xylan...... esterase genes, CtAxeA and CtAxeB, in Pichia pastoris. The recombinant proteins, rCtAxeA and rCtAxeB, released acetic acids from p-nitrophenyl acetate and water-insoluble wheat arabinoxylan. These results indicate that CtAxeA and CtAxeB are true acetyl xylan esterases. For both recombinant esterases, over...

  5. Acidic-alkaline ferulic acid esterase from Chaetomium thermophilum var. dissitum: Molecular cloning and characterization of recombinant enzyme expressed in Pichia pastoris

    DEFF Research Database (Denmark)

    Dotsenko, Gleb; Tong, Xiaoxue; Pilgaard, Bo;

    2016-01-01

    A novel ferulic acid esterase encoding gene CtFae, was successfully cloned from a highly esterase active strain of the thermophile ascomycetous fungus Chaetomium thermophilum var. dissitum; the gene was heterologously expressed in Pichia pastoris KM71H. The recombinant enzyme (CtFae) was purified...

  6. Structural characterization of the principal mRNA-export factor Mex67–Mtr2 from Chaetomium thermophilum

    International Nuclear Information System (INIS)

    The crystal structures of the individual domains of the Mex67–Mtr2 complex from C. thermophilum have been determined and their arrangement in solution has been studied by SAXS. Members of the Mex67–Mtr2/NXF–NXT1 family are the principal mediators of the nuclear export of mRNA. Mex67/NXF1 has a modular structure based on four domains (RRM, LRR, NTF2-like and UBA) that are thought to be present across species, although the level of sequence conservation between organisms, especially in lower eukaryotes, is low. Here, the crystal structures of these domains from the thermophilic fungus Chaetomium thermophilum are presented together with small-angle X-ray scattering (SAXS) and in vitro RNA-binding data that indicate that, not withstanding the limited sequence conservation between different NXF family members, the molecules retain similar structural and RNA-binding properties. Moreover, the resolution of crystal structures obtained with the C. thermophilum domains was often higher than that obtained previously and, when combined with solution and biochemical studies, provided insight into the structural organization, self-association and RNA-binding properties of Mex67–Mtr2 that facilitate mRNA nuclear export

  7. Structural characterization of the principal mRNA-export factor Mex67–Mtr2 from Chaetomium thermophilum

    Energy Technology Data Exchange (ETDEWEB)

    Aibara, Shintaro; Valkov, Eugene; Lamers, Meindert H. [MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH (United Kingdom); Dimitrova, Lyudmila; Hurt, Ed [Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg (Germany); Stewart, Murray, E-mail: ms@mrc-lmb.cam.ac.uk [MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH (United Kingdom)

    2015-06-27

    The crystal structures of the individual domains of the Mex67–Mtr2 complex from C. thermophilum have been determined and their arrangement in solution has been studied by SAXS. Members of the Mex67–Mtr2/NXF–NXT1 family are the principal mediators of the nuclear export of mRNA. Mex67/NXF1 has a modular structure based on four domains (RRM, LRR, NTF2-like and UBA) that are thought to be present across species, although the level of sequence conservation between organisms, especially in lower eukaryotes, is low. Here, the crystal structures of these domains from the thermophilic fungus Chaetomium thermophilum are presented together with small-angle X-ray scattering (SAXS) and in vitro RNA-binding data that indicate that, not withstanding the limited sequence conservation between different NXF family members, the molecules retain similar structural and RNA-binding properties. Moreover, the resolution of crystal structures obtained with the C. thermophilum domains was often higher than that obtained previously and, when combined with solution and biochemical studies, provided insight into the structural organization, self-association and RNA-binding properties of Mex67–Mtr2 that facilitate mRNA nuclear export.

  8. Ecology of Thermophilic Fungi in Mushroom Compost, with Emphasis on Scytalidium thermophilum and Growth Stimulation of Agaricus bisporus Mycelium

    OpenAIRE

    Straatsma, Gerben; Samson, Robert A.; Olijnsma, Tineke W.; Op den Camp, Huub J. M.; Gerrits, Jan P. G.; Van Griensven, Leo J. L. D.

    1994-01-01

    Twenty-two species of thermophilic fungi were isolated from mushroom compost. Scytalidium thermophilum was present in the compost ingredients, fresh straw, horse droppings, and drainage from compost and dominated the fungal biota of compost after preparation. Of 34 species of thermophilic fungi tested, 9 promoted mycelial growth of Agaricus bisporus on sterilized compost: Chaetomium thermophilum, an unidentified Chaetomium sp., Malbranchea sulfurea, Myriococcum thermophilum, S. thermophilum, ...

  9. Identification and characterization of diverse xylanases from thermophilic and thermotolerant fungi

    Directory of Open Access Journals (Sweden)

    Bhat, M. K.

    2006-07-01

    Full Text Available Thirteen fungal isolates included in this study expressed multiple xylanase isoforms as observed by xylan zymograms of polyacrylamide gel electrophoresis (PAGE and isoelectrofocussing (IEF fractionated proteins. Eighty-three xylanases produced by these thermophilic and thermotolerant strains were detected using the IEF profiling technique. Xylanases identified on the basis of their isoelectric points (pI were functionally diverse and exhibited differential catalytic activities against various xylan types (birch wood xylan, larch wood xylan, oat spelt xylan, rye arabino xylan and wheat arabino xylan as well as debranched arabinan. Thermophilic isolates, Chaetomium thermophilum, Humicola insolens, Melanocarpus sp., Malbranchea sp. and Thermoascus aurantiacus, were found to produce alkaline active xylanases that showed a bleach boosting effect on Decker pulp resulting in increased brightness (1.60-2.04 ISO units.

  10. 微波诱变法筛选木聚糖酶高产球毛壳霉菌株%Screening of high xylanase-producing Chaetomium globosum strain by microwave mutagenesis

    Institute of Scientific and Technical Information of China (English)

    姚笛; 王艳丹; 杨健; 于长青; 钱丽丽; 佟丹丹

    2012-01-01

    Objective To screen a high xylanase-producing Chaetomium globosum strain with genetic stability by microwave mutagenesis. Methods C. Globosiun strain was activated and prepared into spore suspension, then subjected to radiation at various powers for 60 s. The strain was subjected to microwave mutagenesis for various seconds at the selected radiation power with a lethal rate of about 80% and, after preliminary and repeat screenings, determined for xylanase activity by DNS method, based on which a high xylanase-producing strain was screened and analyzed for genetic stability. Results The lethal rate of spores of C. Gtobosum was 89. 5% after microwave radiation at a power of 240 W for 80 s. High xylanase-producing C. Globosum W80-8 strain was obtained after mutagenesis and screening, of which the xylanase activity was 7 520 U/ml and increased by 124% as compared with that of original strain. Neither decrease of xylanase activity nor in situ back mutation was observed in W80-8 strain after subculture for 6 passages. Conclusion A high xylanase-producing C. Globosum strain with genetic stability was successfully screened.%目的 微波诱变法筛选遗传稳定的木聚糖酶高产球毛壳霉菌株.方法 活化球毛壳霉菌种,制备孢子悬液,在不同功率条件下对其进行辐照处理60s,选择致死率在80%左右的辐照功率,在此功率条件下对其进行不同时间的微波诱变,经初筛和复筛后,采用DNS法测定木聚糖酶活性,筛选木聚糖酶高产菌株,并分析其传代稳定性.结果 在微波辐射时间80 s,功率240 W条件下处理的球毛壳霉孢子,致死率为89.5%;经诱变及菌种筛选,获得1株木聚糖酶高产菌株W80-8,其酶活力为7520U/ml,比出发菌株提高了124%;经6次传代培养,W80-8株木聚糖酶活力未见明显降低,未发生原位回复突变.结论 成功筛选获得1株遗传稳定的木聚糖酶高产球毛壳霉菌株.

  11. Molecular cloning and characterization of a GH11 endoxylanase from Chaetomium globosum, and its use in enzymatic pretreatment of biomass

    DEFF Research Database (Denmark)

    Singh, Raushan Kumar; Tiwari, Manish Kumar; Kim, Dongwook;

    2013-01-01

    An endo-1,4-β-xylanase gene, xylcg, was cloned from Chaetomium globosum and successfully expressed in Escherichia coli. The complete gene of 675 bp was amplified, cloned into the pET 28(a) vector, and expressed. The optimal conditions for the highest activity of the purified recombinant XylCg were......Cg belongs to the GH11 family. Rice straw pretreated with XylCg showed 30 % higher conversion yield than the rice straw pretreated with a commercial xylanase. Although xylanases have been characterized from fungal and bacterial sources, C. globosum XylCg is distinguished from other xylanases by its high...

  12. Probing the role of sigma π interaction and energetics in the catalytic efficiency of endo-1,4-β-xylanase

    DEFF Research Database (Denmark)

    Singh, Raushan Kumar; Tiwari, Manish Kumar; Kim, In-Won;

    2012-01-01

    Chaetomium globosum endo-1,4-β-xylanase (XylCg) is distinguished from other xylanases by its high turnover rate (1,860 s(-1)), the highest ever reported for fungal xylanases. One conserved amino acid, W48, in the substrate binding pocket of wild-type XylCg was identified as an important residue...

  13. Autohydrolysis of plant xylans by apoplastic expression of thermophilic bacterial endo-xylanases

    DEFF Research Database (Denmark)

    Borkhardt, Bernhard; Harholt, Jesper; Ulvskov, Peter Bjarne;

    2010-01-01

    The genes encoding the two endo-xylanases XynA and XynB from the thermophilic bacterium Dictyoglomus thermophilum were codon optimized for expression in plants. Both xylanases were designed to be constitutively expressed under the control of the CaMV 35S promoter and targeted to the apoplast. Tra...... treatment of wildtype and transgenic extracts from dry stems showed a decrease in the molecular weight of xylans from transgenic stems....

  14. Heliotropium thermophilum (Boraginaceae), a new taxon from SW Anatolia, Turkey

    DEFF Research Database (Denmark)

    Tan, Kit; Celik, Ali; Gemici, Yusuf;

    2008-01-01

    Heliotropium thermophilum Kit Tan, A. Çelik & Y. Gemici (Boraginaceae), is described as a species new to science and illustrated. Its diploid chromosome number of 2n = 16 is a first report. It is restricted to the province of Aydin bordering on Denizli in SW Anatolia and is of interest on account...

  15. Cloning, sequencing, and sequence analysis of two novel plasmids from the thermophilic anaerobic bacterium Anaerocellum thermophilum

    DEFF Research Database (Denmark)

    Clausen, Anders; Mikkelsen, Marie Just; Schrøder, I.;

    2004-01-01

    The nucleotide sequence of two novel plasmids isolated from the extreme thermophilic anaerobic bacterium Anaerocellum thermophilum DSM6725 (A. thermophilum), growing optimally at 70degreesC, has been determined. pBAS2 was found to be a 3653 bp plasmid with a GC content of 43%, and the sequence...

  16. First Spanish case of onychomycosis caused by Chaetomium globosum.

    Science.gov (United States)

    Aspiroz, Carmen; Gené, Josepa; Rezusta, Antonio; Charlez, Luis; Summerbell, Richard C

    2007-05-01

    Members of the fungal genus Chaetomium usually colonize cellulose-containing plant remains but on rare occasions may cause opportunistic mycoses and cutaneous infection in otherwise healthy individuals. To our knowledge, there have been only five credible descriptions of onychomycosis caused by members of this genus and only two of these contained information on therapy. We describe the first case of Chaetomium globosum onychomycosis recorded in Spain. The etiologic significance of the fungus was confirmed by its repeated isolation at different times, to the exclusion of dermatophytes. Clinically, the affected nails showed an excellent response to terbinafine and complete cure appeared to have been attained. PMID:17464849

  17. Implantation phaeohyphomycosis caused by a non-sporulating Chaetomium species.

    Science.gov (United States)

    Najafzadeh, M J; Fata, A; Naseri, A; Keisari, M Saradeghi; Farahyar, S; Ganjbakhsh, M; Ziaee, M; Dolatabadi, S; de Hoog, G S

    2014-06-01

    We report the case of a 66-year-old Iranian woman with a phaeohyphomycotic cyst (approximately 3×2.5cm in size) on the right lateral side of the neck. She had dysphagia and hoarseness, without any pain. She complained about discharge of black liquid on the skin and irritation. Histological examination of biopsy fragments from the lesions showed septate, branched brown hyphae. The fungus was cultured, but sporulation remained absent from 4- week-old cultures on Sabouraud dextrose agar (SDA), malt extract agar (MEA), potato dextrose agar (PDA), and water agar with sterile filter paper. Identification with the genus Chaetomium was achieved by sequencing the internal transcribed spacer (ITS) and the small subunit (SSU) domains of the rDNA gene and comparison with sequences held at GenBank and at the Centraalbureau voor Schimmelcultures (CBS). Sequencing of the SSU rRNA gene reveals this strain as belonging to the genus Chaetomium. The sequence of ITS did not fully match with any sequence of available ex-type strains of Chaetomium, Thielavia, Madurella and Papulaspora and hence might belong to an undescribed species. However, without diagnostic morphological features the taxon cannot be introduced as a novel member of the genus Chaetomium. After local excision of the cyst and antifungal therapy with ketoconazole (200mg twice a day), the lesion regressed and healed completely. PMID:24246716

  18. Pangola grass colonized with Scytalidium thermophilum for production of Agaricus bisporus.

    Science.gov (United States)

    Sanchez, Jose E; Mejia, Laura; Royse, Daniel J

    2008-02-01

    This work had the dual objective of selecting a substrate for rapid mycelial growth of Scytalidium thermophilum and then comparing the growth and production of a brown variety of Agaricus bisporus on substrate non-colonized and colonized with S. thermophilum. Mycelial growth of S. thermophilum at 45 degrees C was significantly greater on potato dextrose yeast extract agar (0.58 mm/h) as compared to malt extract glucose agar (0.24 mm/h) and yeast extract glucose agar (0.44 mm/h). On cereal grain, S. thermophilum grew significantly faster on rice (0.31 mm/h) compared to sorghum (0.22 mm/h) and millet (0.18 mm/h). It also grew faster on Pangola grass (0.49 mm/h) compared to corncobs (0.30 mm/h) and sawdust (0.18 mm/h). Colonization of Pangola grass with S. thermophilum was influenced by the addition of calcium salts in the form of gypsum, hydrated lime and ground limestone. For production of A. bisporus, biological efficiency (BE) on pasteurized Pangola grass pre-colonized by S. thermophilum for 4 days at 45 degrees C was more than twice (26.4%) that on grass non-colonized by S. thermophilum (11.0%). The addition of 2% hydrated lime to Pangola grass prior to colonization by S. thermophilum resulted in an additional doubling of BE of mushroom production (48.1%). These results show the possibility of developing a non-composted substrate method for producing A. bisporus without autoclaving the substrate. PMID:17331714

  19. Chaetomium and Stachybotrys in water-damaged buildings

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Lewinska, Anna Malgorzata; Nielsen, Jakob Blæsbjerg;

    Fungal growth occurs when parts of the building envelope get very wet due to unfortunate combinations of factors, e.g. thermal bridges/lack of ventilation, shoddy foundations/flooding or leaks in build-in pipes. Chaetomium and Stachybotrys are not as abundant as Penicillium and Aspergillus (Table......), however, they may produce volatiles and microparticles that can cause health problems. They are common in wet walls constructed of wood fibre board (OSB/plywood) and gypsum board....

  20. FERROFLUIDS INFLUENCE ON DEHYDROGENASES ACTIVITY IN CELLULOLYTIC FUNGUS CHAETOMIUM GLOBOSUM

    OpenAIRE

    Alexandru Manoliu; Lacramioara Oprica; Zenovia Olteanu; Dorina Creanga

    2003-01-01

    he activity of dehy drogenases was studied after ferrofluids supply ing in the culture medium of Chaetomium globosum. Spectral measurements were carried out after 7 and, respectively , 11 day s of growth. Different results were noticed for different ferrofluids concentrations: 20, 40, 60, 80 and 100 μl/L. Inhibitory or stimulatory ferrofluids effect was obtained depending on the nature of the investigated enzyme.

  1. Analysis of the tryptophanase expression in Symbiobacterium thermophilum in a coculture with Geobacillus stearothermophilus.

    Science.gov (United States)

    Watsuji, Tomo-O; Takano, Hideaki; Yamabe, Tomoya; Tamazawa, Satoshi; Ikemura, Hiroka; Ohishi, Takanori; Matsuda, Tohyo; Shiratori-Takano, Hatsumi; Beppu, Teruhiko; Ueda, Kenji

    2014-12-01

    The tryptophanase-positive Symbiobacterium thermophilum is a free-living syntrophic bacterium that grows effectively in a coculture with Geobacillus stearothermophilus. Our studies have shown that S. thermophilum growth depends on the high CO2 and low O2 condition established by the precedent growth of G. stearothermophilus. The use of an anoxic atmosphere containing high CO2 allows S. thermophilum to grow independently of G. stearothermophilus, but the cellular yield is ten times lower than that achieved in the coculture. In this study, we characterized the coculture-dependent expression and activity of tryptophanase in S. thermophilum. S. thermophilum cells accumulated a marked amount of indole in a coculture with G. stearothermophilus, but not in the bacterium's pure culture irrespective of the addition of tryptophan. S. thermophilum cells accumulated indole in its pure culture consisting of conditioned medium (medium supplied with culture supernatant of G. stearothermophilus). Proteomic analysis identified the protein specifically produced in the S. thermophilum cells grown in conditioned medium, which was a tryptophanase encoded by tna2 (STH439). An attempt to isolate the tryptophanase-inducing component from the culture supernatant of G. stearothermophilus was unsuccessful, but we did discover that the indole accumulation occurs when 10 mM bicarbonate is added to the medium. RT-PCR analysis showed that the addition of bicarbonate stimulated transcription of tna2. The transcriptional start site, identified within the tna2 promoter, was preceded by the -24 and -12 consensus sequences specified by an alternative sigma factor, σ(54). The evidence suggests that the transcription of some genes involved in amino acid metabolism is σ(54)-dependent, and that a bacterial enhancer-binding protein containing a PAS domain controls the transcription under the presence of high levels of bicarbonate.

  2. Nutrient requirements and growth physiology of the photoheterotrophic Acidobacterium, Chloracidobacterium thermophilum

    Directory of Open Access Journals (Sweden)

    Donald A Bryant

    2015-03-01

    Full Text Available A novel thermophilic, microaerophilic, anoxygenic and chlorophototrophic member of the phylum Acidobacteria, Chloracidobacterium thermophilum strain BT, was isolated from a cyanobacterial enrichment culture derived from microbial mats associated with Octopus Spring, Yellowstone National Park, Wyoming. C. thermophilum is strictly dependent on light and oxygen and grows optimally as a photoheterotroph at irradiance values between 20 to 50 µmol photons m-2 s-1. C. thermophilum is unable to synthesize branched-chain amino acids, L-lysine, and vitamin B12, which are required for growth. Although the organism lacks genes for autotrophic carbon fixation, bicarbonate is also required. Mixtures of other amino acids and 2-oxoglutarate stiumulate growth. As suggested from genomic sequence data, C. thermophilum requires a reduced sulfur source such as thioglycolate, cysteine, methionine, or thiosulfate. The organism can be grown in a defined medium at 51°C (Topt; range 44 to 58°C in the pH range 5.5 to 9.5 (pHopt = ~7.0. Using the defined growth medium and optimal conditions, it was possible to isolate new C. thermophilum strains directly from samples of hot spring mats Yellowstone National Park, Wyoming. The new isolates differ from the type strain with respect to pigment composition, morphology in liquid culture, and temperature adaptation.

  3. Phylogenetic reassessment of the Chaetomium globosum species complex.

    Science.gov (United States)

    Wang, X W; Lombard, L; Groenewald, J Z; Li, J; Videira, S I R; Samson, R A; Liu, X Z; Crous, P W

    2016-06-01

    Chaetomium globosum, the type species of the genus, is ubiquitous, occurring on a wide variety of substrates, in air and in marine environments. This species is recognised as a cellulolytic and/or endophytic fungus. It is also known as a source of secondary metabolites with various biological activities, having great potential in the agricultural, medicinal and industrial fields. On the negative side, C. globosum has been reported as an air contaminant causing adverse health effects and as causal agent of human fungal infections. However, the taxonomic status of C. globosum is still poorly understood. The contemporary species concept for this fungus includes a broadly defined morphological diversity as well as a large number of synonymies with limited phylogenetic evidence. The aim of this study is, therefore, to resolve the phylogenetic limits of C. globosum s.str. and related species. Screening of isolates in the collections of the CBS-KNAW Fungal Biodiversity Centre (The Netherlands) and the China General Microbiological Culture Collection Centre (China) resulted in recognising 80 representative isolates of the C. globosum species complex. Thirty-six species are identified based on phylogenetic inference of six loci, supported by typical morphological characters, mainly ascospore shape. Of these, 12 species are newly described here. Additionally, C. cruentum, C. mollipilium, C. rectum, C. subterraneum and two varieties of C. globosum are synonymised under C. globosum s.str., and six species are resurrected, i.e. C. angustispirale, C. coarctatum, C. cochliodes, C. olivaceum, C. spiculipilium and C. subglobosum. Chaetomium ascotrichoides is segregated from C. madrasense and the genus name Chaetomidium is rejected. Five species, including C. globosum s.str., are typified here to stabilise their taxonomic status. A further evaluation of the six loci used in this study as potential barcodes indicated that the 28S large subunit (LSU) nrDNA and the internal transcribed

  4. Genome sequence of Symbiobacterium thermophilum, an uncultivable bacterium that depends on microbial commensalism

    OpenAIRE

    Ueda, Kenji; YAMASHITA Atsushi; Ishikawa, Jun; Shimada, Masafumi; Watsuji, Tomo-o; Morimura, Kohji; Ikeda, Haruo; Hattori, Masahira; Beppu, Teruhiko

    2004-01-01

    Symbiobacterium thermophilum is an uncultivable bacterium isolated from compost that depends on microbial commensalism. The 16S ribosomal DNA-based phylogeny suggests that this bacterium belongs to an unknown taxon in the Gram-positive bacterial cluster. Here, we describe the 3.57 Mb genome sequence of S.thermophilum. The genome consists of 3338 protein-coding sequences, out of which 2082 have functional assignments. Despite the high G + C content (68.7%), the genome is closest to that of Fir...

  5. Growth characteristics of the thermophilic fungus Scytalidium thermophilum in relation to production of mushroom compost.

    NARCIS (Netherlands)

    Wiegant, W.M.

    1992-01-01

    Scytalidium thermophilum is an important thermophilic fungus in the production of mushroom compost. I investigated the characteristics of this organism and present a simple model with which fungal growth in compost can be described. The model is used to predict better circumstances for rapid indoor

  6. Xylanase production by Trichoderma harzianum E58

    Energy Technology Data Exchange (ETDEWEB)

    Senior, D.J.; Mayers, P.R.; Saddler, J.N. (Fortintek Canada Corp., Ottawa, ON (Canada). Dept. of Biotechnology and Chemistry)

    1989-12-01

    Growth of Trichoderma harzianum E58 on hemicellulose-rich media, both in batch and fermentor cultures, resulted in independent profiles of the production of xylanase and endoglucanase enzymes. Dramatic differences in the ratio of xylanase to endoglucanase activities were observed among cultures grown on cellulose-rich Solka Floc and xylan. These results indicated that the induction of xylanases and cellulases was likely to be under separate regulatory control. The specific activity and amount of xylanases produced were found to be dependent on the concentration of xylan in the growth media. Growth on oat spelts xylan or the hemicellulose-rich, watersoluble fraction from steam-treated aspenwood (SEA-WS) greatly enhanced the production of xylanases and xylosidase in the culture filtrates. Constitutive levels of xylanase and endoglucanase enzymes were detected during growth of the fungus on glucose. (orig.).

  7. [Chemical constituents from endophyte Chaetomium globosum in Imperata cylindrical].

    Science.gov (United States)

    Shen, Li; Zhu, Li; Wei, Zhong-qi; Li, Xiao-wen; Li, Ming; Song, Yong-chun

    2015-12-01

    Isolation and purification of chemical constituents from solid culture of endophyte Chaetomium globosum in Imperata cylindrical was performed through silica gel column chromatography, gel filtration over Sephadex LH-20 and preparative HPLC. Nine compounds were obtained and their structures were determined as chaetoglobosin F(1), chaetoglobosin Fex(2), chaetoglobosin E(3) cytoglobosin A(4), penochalasin C(S), isochaetoglobosin D (6), N-benzoylphenylalaninyl-N-benzoyphenylalaninate(7), uracil(8) and 5-methyluracil(9), respectively, based on HR-MS and NMR data and comparison with literatures. Compound 7 was isolated from Chaeeomium sp. for the first time. In vitro cytotoxicity of compounds was evaluated using MTT mothed and 1,3,4 and 5 showed inhibition activity to the human cervical carcinoma cell HeLa with IC50 values of 99.43, 23.77, 97.92, 86.25 micromol x L(-1), while positive cotolocisnin Ad apno1ch alse IC50 24.33 micromol x L(-1). PMID:27141677

  8. INDUSTRIAL APPLICATIONS AND FUTURE PROSPECTS OF MICROBIAL XYLANASES: A REVIEW

    OpenAIRE

    Saurabh Sudha Dhiman; Jitender Sharma; Bindu Battan

    2008-01-01

    Microbial enzymes such as xylanases enable new technologies for industrial processes. Xylanases (xylanolytic enzyme) hydrolyze complex polysaccharides like xylan. Research during the past few decades has been dedicated to enhanced production, purification, and characterization of microbial xylanase. But for commercial applications detailed knowledge of regulatory mechanisms governing enzyme production and functioning should be required. Since application of xylanase in the commercial sector i...

  9. Production and Optimization of Exo and Endocellulases from Thermophilic Fungi Scytalidium thermophilum SKESMBKU02

    Directory of Open Access Journals (Sweden)

    Sriyamjalla SANTOSHKUMAR

    2016-01-01

    Full Text Available The study aimed at isolation and screening of thermophilic cellulase producer, optimization and stability studies for maximum cellulase production. Fifteen thermophilic cellulase producing fungi were isolated from thermogenic habitats (vegetable market compost, mushroom compost, horse dung, municipal waste, nests of birds, decomposing litter, soils from furnace area, cattle dung, zoo dump, and industrial waste. of Telangana. All the fungal isolates were screened for their ability to produce cellulases. Scytalidium thermophilum SKESMBKU02 showed the highest cellulase activity in screening and was selected for further studies. The results showed that S. thermophilum SKESMBKU02 found to have high cellulolytic activity at 45 °C and pH 5.0 - 6.0. Optimization of enzyme production was studied in different carbon and nitrogen sources. The endo and exoglucanase activities were higher in media containing glucose as their carbon source followed by xylose. Yeast extract and peptone were good nitrogen sources for endoglucanase and exoglucanase activity respectively. The organism showed maximum dry weight in (NH42SO4 and NH4Cl. The exo and endocellulases produced by the S. thermophilum SKESMBKU02 were highly stable at pH 8.0 and temperature of 75 °C. The results indicate that the endo and exocellulases produced by the fungi were more stable at high temperature and alkaline pH.

  10. Potentially harmful secondary metabolites produced by indoor Chaetomium species on artificially and naturally contaminated building materials

    DEFF Research Database (Denmark)

    Dosen, Ina; Nielsen, Kristian Fog; Clausen, Geo;

    2016-01-01

    The presence of the fungal genus Chaetomium and its secondary metabolites in indoor environments is suspected to have a negative impact on human health and wellbeing. About 200 metabolites have been currently described from Chaetomium spp., but only the bioactive compound group, chaetoglobosins......, have been screened for, and thus detected in buildings. In this study, we used a liquid chromatography-high resolution mass spectrometry approach to screen both artificially and naturally infected building materials for all the Chaetomium metabolites described in the literature. Pure agar cultures were...... also investigated in order to establish differences between metabolite production in vitro and on building materials as well as comparison to non-indoor reference strains. On building materials six different chaetoglobosins were detected in total concentrations of up to 950 mg/m2 from C. globosum along...

  11. The influence of the petroleum ferrofluids upon the cellulosolytic fungi Chaetomium globosum Kunze:Fr

    Science.gov (United States)

    Manoliu, Al.; Antohe, Lacramioara; Creanga, Dorina E.; Cotae, C.

    1999-07-01

    We present a study on the development of the cellulosolytic fungi Chaetomium globosum Kunze:Fr. under the influence of a petroleum ferrofluid, added at various concentrations to the culture medium. A positive influence of the ferrofluid was revealed at the level of the growth rate during the first week of the experiment. Further, the biomass accumulation rate was diminished in the sample in comparison to the control without the addition of ferrofluid. The ubiquitous capacity of the fungi for iron internalization under the form of complex combinations known as siderophores, is probably related to the observed behavior of Chaetomium globosum Kunze:Fr.

  12. Microbial xylanases: engineering, production and industrial applications.

    Science.gov (United States)

    Juturu, Veeresh; Wu, Jin Chuan

    2012-01-01

    Enzymatic depolymerization of hemicellulose to monomer sugars needs the synergistic action of multiple enzymes, among them endo-xylanases (EC 3.2.1.8) and β-xylosidases (EC 3.2.1.37) (collectively xylanases) play a vital role in depolymerizing xylan, the major component of hemicellulose. Recent developments in recombinant protein engineering have paved the way for engineering and expressing xylanases in both heterologous and homologous hosts. Functional expression of endo-xylanases has been successful in many hosts including bacteria, yeasts, fungi and plants with yeasts being the most promising expression systems. Functional expression of β-xylosidases is more challenging possibly due to their more complicated structures. The structures of endo-xylanases of glycoside hydrolase families 10 and 11 have been well elucidated. Family F/10 endo-xylanases are composed of a cellulose-binding domain and a catalytic domain connected by a linker peptide with a (β/α)8 fold TIM barrel. Family G/11 endo-xylanases have a β-jelly roll structure and are thought to be able to pass through the pores of hemicellulose network owing to their smaller molecular sizes. The structure of a β-D-xylosidase belonging to family 39 glycoside hydrolase has been elucidated as a tetramer with each monomer being composed of three distinct regions: a catalytic domain of the canonical (β/α)8--TIM barrel fold, a β-sandwich domain and a small α-helical domain with the enzyme active site that binds to D-xylooligomers being present on the upper side of the barrel. Glycosylation is generally considered as one of the most important post-translational modifications of xylanases, but a few examples showed functional expression of eukaryotic xylanases in bacteria. The optimal ratio of these synergistic enzymes is very important in improving hydrolysis efficiency and reducing enzyme dosage but has hardly been addressed in literature. Xylanases have been used in traditional fields such as food, feed

  13. PCR and real-time PCR primers developed for detection and identification of Bifidobacterium thermophilum in faeces

    Directory of Open Access Journals (Sweden)

    Mini Raffaella

    2008-10-01

    Full Text Available Abstract Background Culture-independent methods based on the 16S ribosomal RNA molecule are nowadays widely used for assessment of the composition of the intestinal microbiota, in relation to host health or probiotic efficacy. Because Bifidobacterium thermophilum was only recently isolated from human faeces until now, no specific real-time PCR (qPCR assay has been developed for detection of this species as component of the bifidobacterial community of the human intestinal flora. Results Design of specific primers and probe was achieved based on comparison of 108 published bifidobacterial 16S rDNA sequences with the recently published sequence of the human faecal isolate B. thermophilum RBL67. Specificity of the primer was tested in silico by similarity search against the sequence database and confirmed experimentally by PCR amplification on 17 Bifidobacterium strains, representing 12 different species, and two Lactobacillus strains. The qPCR assay developed was linear for B. thermophilum RBL67 DNA quantities ranging from 0.02 ng/μl to 200 ng/μl and showed a detection limit of 105 cells per gram faeces. The application of this new qPCR assay allowed to detect the presence of B. thermophilum in one sample from a 6-month old breast-fed baby among 17 human faecal samples tested. Additionally, the specific qPCR primers in combination with selective plating experiments led to the isolation of F9K9, a faecal isolate from a 4-month old breast-fed baby. The 16S rDNA sequence of this isolate is 99.93% similar to that of B. thermophilum RBL67 and confirmed the applicability of the new qPCR assay in faecal samples. Conclusion A new B. thermophilum-specific qPCR assay was developed based on species-specific target nucleotides in the 16S rDNA. It can be used to further characterize the composition of the bifidobacterial community in the human gastrointestinal tract. Until recently, B. thermophilum was considered as a species of animal origin, but here we

  14. Characterization of cellulase enzyme produced by Chaetomium sp. isolated from books and archives

    Directory of Open Access Journals (Sweden)

    Moza Mohammed AL-Kharousi

    2015-12-01

    Full Text Available Background: Cellulase is an important industrial enzyme used to degrade cellulosic biomass. The demand for cellulase enzyme is continuously increasing because of its applications in various industries. Hence, screening of cellulase producing microorganisms from different sources has gained significant importance. Material and Methods: In this study, fungi isolated from books and archives were screened for their cellulase producing abilities. Four different fungi were isolated from books and archives using potato dextrose agar. Screening of these isolates for cellulase production was carried out using carboxymethyl cellulose broth. The most efficient fungus was subjected to cellulase fermentation and enzymes produced were purified and partially characterized. Results: Four different fungi, Chaetomium sp., Aspergillus niger, Aspergillus nidulans and Penicillium sp., were isolated from books and archives. All the isolates were tested for their ability to producecellulase enzyme. During the primary screening Chaetomium sp. showed good growth and highercellulase activity (155.3±25.6 U/mL in carboxymethyl cellulose medium than the other fungi. The cellulase fermentation study was conducted with Chaetomium sp. using carboxymethyl cellulose asa substrate. During the stationary phase (144 h of the growth, the cellulase activity of Chaetomium sp. was significantly high. The maximum mycelial weight of this fungi was obtained at 168 h. Viscosity of the Chaetomium sp. inoculated fermentation medium continuously decreased until 144 h because of the degradation of carboxymethyl cellulose. During cellulase fermentation, pHincreased from the initial neutral pH to 8.5. Purified cellulase showed a specific activity of 7.3 U/mg. It exhibited maximum activity at 20°C and was stable between pH 5 and 9. Conclusions: Books and archives could be a good source for the isolation of cellulase producing fungi.

  15. Partial purification and characterization of xylanase produced by Penicillium expansum

    OpenAIRE

    André Luiz de Souza Querido; Jorge Luiz Cavalcante Coelho; Elza Fernandes Araújo; Virgínia Maria Chaves-Alves

    2006-01-01

    An extracellular xylanase was found to be the major protein in the filtrate culture of Penicillium expansum when grown on 0.3 % wheat bran, which showed no xylanase multiplicity. The enzime was partial purified by.ammonium sulfate fractioning, molecular exclusion chromatography, ultrafiltration and anion exchange chromatography. The protein eluation profile showed only one form of xylanase that was partially characterized. The activity of purified xylanase was optimal at pH 5.5 and 40 ºC. The...

  16. Draft Genome Sequence of the Photoheterotrophic Chloracidobacterium thermophilum Strain OC1 Found in a Mat at Ojo Caliente

    OpenAIRE

    Hallenbeck, Patrick C.; Grogger, Melanie; Mraz, Megan; Veverka, Donald

    2016-01-01

    Metagenomics of an enrichment culture from a New Mexico hot spring allowed the description of a draft genome of a Chloracidobacterium thermophilum strain for the first time outside Yellowstone National Park with a surprisingly high degree of identity with the type strain.

  17. Biocontrol potential of Steinernema thermophilum and its symbiont Xenorhabdus indica against lepidopteran pests: virulence to egg and larval stages

    Science.gov (United States)

    Under laboratory conditions, the biocontrol potential of Steinernema thermophilum was tested against eggs and larval stages of two important lepidopteran insect pests, Helicoverpa armigera and Spodoptera litura (polyphagous pests), as well as Galleria mellonella (used as a model host) . In terms of ...

  18. Structural model and spectroscopic characteristics of the FMO antenna protein from the aerobic chlorophototroph, Candidatus Chloracidobacterium thermophilum

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Jianzhong; Tsukatani, Yusuke; Cui, Weidong; Zhang, Hao; Gross, Michael L; Bryant, Donald A; Blankenship, R. E.

    The Fenna–Matthews–Olson protein (FMO) binds seven or eight bacteriochlorophyll a (BChl a) molecules and is an important model antenna system for understanding pigment-protein interactions and mechanistic aspects of photosynthetic light harvesting. FMO proteins of green sulfur bacteria (Chlorobiales) have been extensively studied using a wide range of spectroscopic and theoretical approaches because of their stability, the spectral resolution of their pigments, their water-soluble nature, and the availability of high-resolution structural data. We obtained new structural and spectroscopic insights by studying the FMO protein from the recently discovered, aerobic phototrophic acidobacterium, Candidatus Chloracidobacterium thermophilum. Native C. thermophilum FMO is a trimer according to both analytical gel filtration and native-electrospray mass spectrometry. Furthermore, the mass of intact FMO trimer is consistent with the presence of 21–24 BChl a in each. Homology modeling of the C. thermophilum FMO was performed by using the structure of the FMO protein from Chlorobaculum tepidum as a template. C. thermophilum FMO differs from C. tepidum FMO in two distinct regions: the baseplate, CsmA-binding region and a region that is proposed to bind the reaction center subunit, PscA. C. thermophilum FMO has two fluorescence emission peaks at room temperature but only one at 77 K. Temperature-dependent fluorescence spectroscopy showed that the two room-temperature emission peaks result from two excited-state BChl a populations that have identical fluorescence lifetimes. Modeling of the data suggests that the two populations contain 1–2 BChl and 5–6 BChl a molecules and that thermal equilibrium effects modulate the relative population of the two emitting states.

  19. Bioactive secondary metabolites from the endophytic fungus Chaetomium sp. isolated from Salvia officinalis growing in Morocco

    Directory of Open Access Journals (Sweden)

    Ebel R.

    2009-01-01

    Full Text Available This study reports the chemical investigation and cytotoxic activity of the secondary metabolites produced by the endophytic fungus Chaetomium sp. isolated from Salvia officinalis growing in Morocco. This plant was collected from the Beni-Mellal Mountain in Morocco and belongs to the Lamiaceae family and is named in Morocco “Salmia”. The endophytic fungus Chaetomium sp. was isolated from the tissues of the stem of this plant. The fungal strain was identified by PCR. The crude organic extract of the fungal strain was proven to be active when tested for cytotoxicity against L5178Y mouse lymphoma cells. Chemical investigation of the secondary metabolites showed that cochliodinol is the main component beside isocochliodinol. The structures of the isolated compounds were determined on the basis of NMR analysis (1H, 13C, COSY and HMBC as well as by mass spectrometry using ESI (Electron Spray Ionisation as source.

  20. Indole diketopiperazines from endophytic Chaetomium sp 88194 induce breast cancer cell apoptotic death.

    Science.gov (United States)

    Wang, Fu-qian; Tong, Qing-yi; Ma, Hao-ran; Xu, Hong-feng; Hu, Song; Ma, Wei; Xue, Yong-bo; Liu, Jun-jun; Wang, Jian-ping; Song, Hong-ping; Zhang, Jin-wen; Zhang, Geng; Zhang, Yong-hui

    2015-03-19

    Diketopiperazines are important secondary metabolites of the fungi with variety bioactivities. Several species belonging to genus Chaetomium produce compounds of this class, such as chetomin. To identify new antitumor agents, secondary metabolites of fungus Chaetomium sp 88194 were investigated and three new indole diketopiperazines, Chaetocochins G (1), Oidioperazines E (2) and Chetoseminudin E (3), along with two known compounds Chetoseminudins C (4) and N-acetyl-β-oxotryptamine (5), were obtained. Chaetocochins G and Chetoseminudin E were recrystallized in CHCl3 containing a small amount of MeOH, and their structures with absolute configuration were established by spectroscopic data interpretation and single-crystal X-ray diffraction analysis. The absolute configuration of Oidioperazines E was defined by comparing of experimental and calculated electronic circular dichroism spectra. These isolates were also evaluated the anticancer activity, and Chaetocochins G displayed more potent cytotoxicity in MCF-7 cells than the common chemotherapeutic agent (5-fluorouracil) associated with G2/M cell cycle arrest. More importantly, Chaetocochins G induced cell apoptotic death via caspase-3 induction and proteolytic cleavage of poly (ADP-ribose) polymerase, concomitantly with increased Bax and decreased Bcl-2 expression. Our findings suggested that indole diketopiperazines from endophytic Chaetomium sp 88194 may be potential resource for developing anti-cancer reagents.

  1. The fungal endophyte Chaetomium globosum negatively affects both above- and belowground herbivores in cotton.

    Science.gov (United States)

    Zhou, Wenqing; Starr, James L; Krumm, Janice L; Sword, Gregory A

    2016-10-01

    Mutualistic plant-endophyte symbioses can benefit plants by increasing host fitness through reductions in herbivory. The fungus, Chaetomium globosum strain TAMU 520, was previously isolated as an endophyte from cotton (Gossypium hirsutum) and can be re-inoculated to systemically colonize cotton plants via seed treatment. We evaluated the potential impacts of the endophyte in cotton on plant parasitic nematodes belowground, along with piercing-sucking and chewing insects aboveground. Endophytic C. globosum inhibited root-knot nematode (Meloidogyne incognita) infection and reduced female reproduction belowground. To confirm the endophytic effect of C. globosum on root-knot nematode, a contact fungicide was applied to remove soil-borne and epiphytic C. globosum Consistent inhibition of nematode activity was observed post-fungicide treatment, with positive C. globosum colonization confirmed within plant tissues. Aboveground, endophytic C. globosum also negatively affected the fecundity of both cotton aphids (Aphis gossypii) and beet armyworms (Spodoptera exigua). Faster development rates and smaller head capsule of beet armyworm larvae were observed when fed Chaetomium-colonized plants. However, no larval weight difference was found between Chaetomium-colonized and control plants. No consistent effect on plant performance was found across experiments. Our findings illustrate how a single facultative fungal endophyte can increase plant systemic resistance against a range of invertebrate herbivores in a major crop. PMID:27451418

  2. Xylanases of marine fungi of potential use for biobleaching of paper pulp

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Muraleedharan, U.; Gaud, V.R.; Mishra, R.

    isolates obtained from marine habitat showed alkaline xylanase activity. The crude enzyme from NIOCC isolate # 3 (Aspergillus niger) with high xylanase activity, cellulase-free and unique properties containing 580 U L-1 of xylanase, could bring about...

  3. Crystallization and preliminary X-ray analysis of a bifunctional catalase-phenol oxidase from Scytalidium thermophilum

    International Nuclear Information System (INIS)

    The bifunctional enzyme catalase-phenol oxidase from S. thermophilum was crystallized by the hanging-drop vapour-diffusion method in space group P21 and diffraction data were collected to 2.8 Å resolution. Catalase-phenol oxidase from Scytalidium thermophilum is a bifunctional enzyme: its major activity is the catalase-mediated decomposition of hydrogen peroxide, but it also catalyzes phenol oxidation. To understand the structural basis of this dual functionality, the enzyme, which has been shown to be a tetramer in solution, has been purified by anion-exchange and gel-filtration chromatography and has been crystallized using the hanging-drop vapour-diffusion technique. Streak-seeding was used to obtain larger crystals suitable for X-ray analysis. Diffraction data were collected to 2.8 Å resolution at the Daresbury Synchrotron Radiation Source. The crystals belonged to space group P21 and contained one tetramer per asymmetric unit

  4. Chaetoglobosins produced by Chaetomium globosum, endophytic fungus found in association with Viguiera robusta Gardn (Asteraceae); Chaetoglobosinas produzidas por Chaetomium globosum, fungo endofitico associado a Viguiera robusta Gardn. (Aasteraceae)

    Energy Technology Data Exchange (ETDEWEB)

    Momesso, Luciano da S.; Kawano, Cristina Y.; Ribeiro, Patricia H.; Nomizo, Auro; Goldman, Gustavo H.; Pupo, Monica T. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: mtpupo@fcfrp.usp.br

    2008-07-01

    Endophytes live in association with host plants during all or part of their life cycle without causing any apparent disease. They are considered outstanding and underexploited sources of novel bioactive compounds. Chaetomium globosum was isolated as an endophytic fungus from the healthy leaves of Viguiera robusta. C. globosum is a remarkable producer of chaetoglobosins, which are typically cytotoxic. In this work, chaetoglobosins B (1), D (2) and E (3) have been produced by the endophytic C. globosum strain. Chaetoglobosin B was evaluated against Jurkat (leukemia) and B16F10 (melanoma) tumoral cells and showed 89.55% and 57.10% of inhibition at 0.1 mg mL{sup -1}, respectively. Chaetoglobosin B also showed weak antibacterial activity against Staphylococcus aureus (MIC 120 {mu}g/mL) and Escherichia coli (MIC 189 {mu}g/mL). (author)

  5. INDUSTRIAL APPLICATIONS AND FUTURE PROSPECTS OF MICROBIAL XYLANASES: A REVIEW

    Directory of Open Access Journals (Sweden)

    Saurabh Sudha Dhiman

    2008-11-01

    Full Text Available Microbial enzymes such as xylanases enable new technologies for industrial processes. Xylanases (xylanolytic enzyme hydrolyze complex polysaccharides like xylan. Research during the past few decades has been dedicated to enhanced production, purification, and characterization of microbial xylanase. But for commercial applications detailed knowledge of regulatory mechanisms governing enzyme production and functioning should be required. Since application of xylanase in the commercial sector is widening, an understanding of its nature and properties for efficient and effective usage becomes crucial. Study of synergistic action of multiple forms and mechanism of action of xylanase makes it possible to use it for bio-bleaching of kraft pulp and for desizing and bio-scouring of fabrics. Results revealed that enzymatic treatment leads to the enhancement in various physical properties of the fabric and paper. This review will be helpful in determining the factors affecting xylanase production and its potential industrial applications in textile, paper, pulp, and other industries.

  6. Novel DNA barcodes for detection, idenfication and tracking of stachybotrys and chaetomium species

    DEFF Research Database (Denmark)

    Lewinska, Anna Malgorzata; Nielsen, Jakob Birkedal; Peuhkuri, Ruut Hannele;

    2014-01-01

    Detection and identification of indoor fungi in water-damaged buildings is crucial for preventi and control of fungal growth. This study focuses on a molecular method called DNA barcoding. evaluates commonly used sequences in DNA barcoding for fungal species identification Chaetomium and...... Stachybotrys. The existing DNA barcodes: ITS, SSU, LSU, B-TUB, CMD, RP and TEF-1α do not give satisfying species resolution to be considered as DNA barcodes for the two genera. Therefore, novel barcodes for them are needed. Barcode potentials, such as HOG1 a NAHA, were identified using bioinformatics and are...

  7. Relatedness of Thermomyces lanuginosus strains producing a thermostable xylanase.

    Science.gov (United States)

    Singh, S; Reddy, P; Haarhoff, J; Biely, P; Janse, B; Pillay, B; Pillay, D; Prior, B A

    2000-08-25

    Properties of an endo-beta-xylanase produced by a locally isolated Thermomyces lanuginosus strain SSBP was compared to seven other T. lanuginosus strains isolated from different geographical regions. Strain SSBP produced the highest xylanase activity of 59600 nkat ml(-1) when cultivated on corn cobs (maize) medium, whereas the seven other strains produced xylanase activities ranging from 6000 to 32000 nkat ml(-1). No cellulase activity was produced by the strains. Despite the variability in the production of xylanase, little difference in the other characteristics of the strains could be found. The optimal temperature and pH for xylanase production by the strains was either 40 or 50 degrees C and between pH 6 and 7, respectively. Optimal xylanase activity of the strains was observed at 70 degrees C and at pH 6 or 6.5. Culture supernatant analysis by SDS-PAGE and isoelectric focusing PAGE of all strains revealed the presence of a single 24.7 kDa and pI 3.9 xylanase. Phylogenetic analysis by PCR amplification and sequencing of the internal transcribed spacer of nuclear rRNA repeat units and 5.8S rDNA revealed no strain diversity. However, random amplified polymorphic DNA analysis pointed to greater diversity and with one primer (5'-GCCCGACGCG-3'), a relationship was established between xylanase levels and the RAPD pattern. PMID:10989171

  8. Rapid detection and identification of Stachybotrys and Chaetomium species using tissue PCR analysis

    DEFF Research Database (Denmark)

    Lewinska, Anna Malgorzata; Peuhkuri, Ruut Hannele; Rode, Carsten;

    2016-01-01

    protein kinase (hogA) and the intergenic region between histone 3 and histone 4 (h3-h4) as well as it introduces a rapid - 3.5 h - protocol for direct Stachybotrys and Chaetomium species identification, which bypasses culture cultivation, DNA extraction and DNA sequencing....... level is essential for health risk assessment and building remediation. This study focuses on molecular identification of two common indoor fungal genera: Stachybotrys and Chaetomium. This study proposes two new DNA barcode candidates for Stachybotrys and Chaetomium: the gene encoding mitogen activated...

  9. Xylanase XYN IV from Trichoderma reesei showing exo- and endo-xylanase activity

    Science.gov (United States)

    A novel xylanase from Trichoderma reesei Rut C30, named XYN IV, was purified from the cellulolytic system of the fungus. The enzyme was discovered on its ability to attack aldotetraohexenuronic acid (HexA-2Xyl-4Xyl-4Xyl, HexA3Xyl3), releasing the reducing-end xylose residue. XYN IV exhibited catalyt...

  10. Functional characterization of Penicillium occitanis Pol6 and Penicillium funiculosum GH11 xylanases

    OpenAIRE

    Berrin, Jean-Guy; Juge, Nathalie; Bhiri, Fatma; Ghorbel, Raoudha; Ellouz Chaabouni, Semia

    2013-01-01

    Xylanases are hemicellulolytic enzymes, which are responsible for the degradation of heteroxylans constituting the lignocellulosic plant cell wall. Xylanases from the GH11 family are considered as true xylanases because of their high substrate specificity. In order to study in depth a crucial difference in the thumb region between two closely related xylanases from Penicillium in terms of kinetic parameters and inhibition sensitivity, the GH11 xylanases from Penicillium occitanis Pol6 (PoXyn3...

  11. Bioconversion of (+)-valencene in submerged cultures of the ascomycete Chaetomium globosum.

    Science.gov (United States)

    Kaspera, Rüdiger; Krings, Ulrich; Nanzad, Tsevegsuren; Berger, Ralf G

    2005-06-01

    Submerged cultures of the ascomycete Chaetomium globosum oxidised the exogenous sesquiterpene (+)-valencene to nootkatone via the stereoselective generation of alpha-nootkatol. Inhibition experiments suggested that the first introduction of oxygen, the rate-limiting step of the bioconversion, may have been catalysed by a cytochrome-P450-monooxygenase. However, nootkatone was not the final metabolite: further flavour-active and inactive, non-volatile oxidation products were identified. (+)-Valencene and the flavour-active mono-oxyfunctionalised transformation products, alpha-nootkatol, nootkatone, and valencene-11,12-epoxide accumulated preferably inside the fungal cells. Di- and poly-oxygenated products, such as nootkatone-11,12-epoxide, were found solely in the culture medium, indicating an active transport of these metabolites into the extracellular compartment during (+)-valencene detoxification. These metabolic properties may have contributed to the high tolerance of the fungus towards the exogenous hydrocarbon. PMID:15602686

  12. Xylanase production by Trichoderma strains in solid substrate fermentation

    Institute of Scientific and Technical Information of China (English)

    Krisztina Kovacs; George Szakacs; Lew Christopher

    2004-01-01

    @@ The importance of microbial enzymes in pulp and paper manufacturing has grown significantly in the last two decades. Solid substrate fermentation (SSF) holds tremendous potential for the production of microbial enzymes of commercial interest. SSF can be of special interest in those processes where the crude fermented product (whole SSF culture, in situ enzyme) may be used directly as the enzyme source. Xylanase preparations practically free of cellulase activity are especially useful for biobleaching of crude cellulose pulps. Thirty-nine Trichoderma isolates have been screened in SSF for xylanase production on hardwood oxygen-delignified soda-aq pulp as carbon source and enzyme inducer.Xylanase activities varied between 0 and 2200 IU/g dry matter (DM) of initial substrate. In most instances, the simultaneously produced cellulase levels were below 1.0 Filter Paper Unit (FPU) /g DM. The xylanase to cellulase activity ratio varied in the range of 5 to 3500. The three most promising isolates (TUB F-1647, TUB F-1658 and TUB F-1684) yielded xylanase activity of 2040,1300 and 1500 IU/g DM xylanase, respectively, and 0.64, 0.43 and 0.43 FPU/g DM cellulase with a xylanase to cellulase activity ratio of 3200, 3000 and 3500, respectively. Wild strains F-1647, F-1658 and F-1684 were isolated from tree bark of Maldives, soils of Peru (last two), respectively.Medium optimization experiments to enhance the xylanase yield and to increase the xylanase to cellulase ratio have also been performed.

  13. Purification and properties of thermostable tryptophanase from an obligately symbiotic thermophile, Symbiobacterium thermophilum.

    Science.gov (United States)

    Suzuki, S; Hirahara, T; Horinouchi, S; Beppu, T

    1991-12-01

    A thermostable tryptophanase was extracted from a thermophilic bacterium, Symbiobacterium thermophilum strain T, which is obligately symbiotic with the thermophilic Bacillus strain S. The enzyme was purified 21-fold to homogeneity with 19% recovery by a series of chromatographies using anion-exchange, hydroxylapatite, hydrophobic interaction, and MonoQ anion-exchange columns. The molecular weight of the purified enzyme was estimated to be approximately 210,000 by gel filtration, while the molecular weight of its subunit was 46,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which indicates that the native enzyme is composed of four homologous subunits. The isoelectric point of the enzyme was 4.9. The tryptophanase was stable to heating at 65 degrees C for 20 min and the optimum temperature for the enzyme activity for 20 min reaction was 70 degrees C. The optimum pH was 7.0. The NH2-terminal amino acid sequence of this tryptophanase shows similarity to that of Escherichia coli K-12, despite a great difference in the thermostability of these two enzymes. The purified enzyme catalyzed the degradation (alpha, beta-elimination) of L-tryptophan into indole, pyruvate, and ammonia in the presence of pyridoxal-5'-phosphate. The Km value for L-tryptophan was 1.47 mM. 5-Hydroxy-L-tryptophan, 5-methyl-DL-tryptophan, L-cysteine, S-methyl-L-cysteine, and L-serine were also used as substrates and converted to pyruvate. The reverse reaction of alpha, beta-elimination of this tryptophanase produced L-tryptophan from indole and pyruvate in the presence of a high concentration of ammonium acetate.

  14. Biotechnology of microbial xylanases: enzymology, molecular biology, and application.

    Science.gov (United States)

    Subramaniyan, S; Prema, P

    2002-01-01

    Xylanases are hydrolases depolymerizing the plant cell wall component xylan, the second most abundant polysaccharide. The molecular structure and hydrolytic pattern of xylanases have been reported extensively and the mechanism of hydrolysis has also been proposed. There are several models for the gene regulation of which this article could add to the wealth of knowledge. Future work on the application of these enzymes in the paper and pulp, food industry, in environmental science, that is, bio-fueling, effluent treatment, and agro-waste treatment, etc. require a complete understanding of the functional and genetic significance of the xylanases. However, the thrust area has been identified as the paper and pulp industry. The major problem in the field of paper bleaching is the removal of lignin and its derivatives, which are linked to cellulose and xylan. Xylanases are more suitable in the paper and pulp industry than lignin-degrading systems. PMID:11958335

  15. XYLANASE PREBLEACHING ON NAOH-AQ WHEAT STRAW PULP

    Institute of Scientific and Technical Information of China (English)

    Caixia Li; Yongjun Deng; Ping Li; Guigan Fang; Shuchai Liu

    2004-01-01

    Before calcium hypochlorite bleaching (H) and chlorination,alkaline extraction, calcium hypochlorite three-stage-bleaching (CEH),we used a kind of hemicellulase, xylanase, to treat wheat straw pulp from Gaoyou Papermill.Xylanase pretreatment contained tow stages, the first stage was xylanase treatment, which was followed by alkaline extraction, the second stage. The xylanase could act on partial lignin and carbohydrate, chiefly xylan. The following alkaline extraction could dissolve something that could not be removed during the first stage. The result of pretreatment was to facilitate penetration of bleaching chemicals, to reduce effective chlorine consumption and to lower pollution loading of bleaching effluent. In the case of these two bleaching processes, the enzymatic pretreatment substantially enhanced the optical properties of the pulps. To calcium hypochlorite bleaching, strength properties of pulps were improved.

  16. XYLANASE PREBLEACHING ON NaOH-AQ WHEAT STRAW PULP

    Institute of Scientific and Technical Information of China (English)

    CaixiaLi; YongjunDeng; PingLi; GuiganFang; ShuchaiLiu

    2004-01-01

    Before calcium hypochlorite bleaching (H) and chlorination, alkaline extraction, calcium hypochlorite three-stage-bleaching (CEH),we used a kind of hemicellulase, xylanase, to treat wheat straw pulpfrom Gaoyou Papermill. Xylanase pretreatment contained tow stages, the first stage was xylanase treatment, which was followed by alkaline extraction, the second stage. The xylanase could act on partial lignin and carbohydrate, chiefly xylan. The following alkaline extraction could dissolve something that could not be removed during the first stage. The result of pretreatment was to facilitate penetration of bleaching chemicals, to reduce effective chlorine consumption and to lower pollution loading of bleaching effluent. In the case of these two bleaching processes, the enzymatic pretreatment substantially enhanced the optical properties of the pulps. To calcium hypochlorite bleaching, strength properties of pulps wereimproved.

  17. Bioactive metabolites from Chaetomium globosum L18, an endophytic fungus in the medicinal plant Curcuma wenyujin.

    Science.gov (United States)

    Wang, Yanhong; Xu, Lei; Ren, Weiming; Zhao, Dan; Zhu, Yanping; Wu, Xiaomin

    2012-02-15

    An endophytic fungus, strain L18, isolated from the medicinal plant Curcuma wenyujin Y.H. Chen et C. Ling was identified as Chaetomium globosum Kunze based on morphological characteristics and sequence data for the internal transcribed spacer (ITS-5.8S-ITS2) of the nuclear ribosomal DNA. A new metabolite named chaetoglobosin X (1), together with three known compounds erogosterol (2), ergosterol 5α,8-peroside (3) and 2-methyl-3-hydroxy indole (4), were isolated from C. globosum L18. Their structures were elucidated by spectroscopic methods including NMR, UV, IR and MS data and comparison with published data. Chaetoglobosin X (1) is hitherto unknown, whereas 2-methyl-3-hydroxy indole (4) is reported for the first time as a fungal metabolite, and erogosterol (2) and ergosterol 5α,8-peroside (3) are known fungal metabolites previously identified in other genera. Chaetoglobosin X (1) exhibited a broader antifungal spectrum and showed the strongest cytotoxic activity against H22 and MFC cancer cell lines.

  18. Chaetochromones A and B, two new polyketides from the fungus Chaetomium indicum (CBS.860.68).

    Science.gov (United States)

    Lu, Keyang; Zhang, Yisheng; Li, Li; Wang, Xuewei; Ding, Gang

    2013-01-01

    Chaetochromones A (1) and B (2), two novel polyketides, were isolated from the crude extract of fungus Chaetomium indicum (CBS.860.68) together with three known analogues PI-3(3), PI-4 (4) and SB236050 (5). The structures of these compounds were determined by HRESI-MS and NMR experiments. Chaetochromones A (1) and B (2) are a member of the polyketides family, which might originate from a similar biogenetic pathway as the known compounds PI-3 (3), PI-4 (4) and SB236050 (5). The biological activities of these secondary metabolites were evaluated against eight plant pathogens, including Alternaria alternata, Ilyonectria radicicola, Trichoderma viride pers, Aspergillus niger, Fusarium verticillioide, Irpex lacteus (Fr.), Poria placenta (Fr.) Cooke and Coriolus versicolor (L.) Quél. Compound 1 displayed moderate inhibitory rate (>60%) against the brown rot fungus Poria placenta (Fr.) Cooke, which causes significant wood decay. In addition, the cytotoxic activities against three cancer cell lines A549, MDA-MB-231, PANC-1 were also tested, without any inhibitory activities being detected. PMID:24013408

  19. Bio-control trials of Chaetomium spirale ND35 against apple canker

    Institute of Scientific and Technical Information of China (English)

    XINYa-fen; SHANGJin-jie

    2005-01-01

    A new endophytic antagonistic fungus, Chaetomium spirale ND35 from Populus tomentosa, was reported. The bio-control trials of C. spirale ND35 against the Valsa Canker of apple were preliminarily investigated. The results of dual culture on PDA plate showed that C. spirale ND35 was capable of strong antagonism against Valsa ceratosperma, and for inhibiting the mycelial growth of V. ceratosperma,.the crude extract of liquid culture of corn steep powder broth was more effective than that one of malt extract broth (MEB). The results of bio-control in greenhouse and field indicated that the disease incidence of apple tree treated with C. spirale ND35 was lower significantly than that treated by other methods. The re-isolation experiment suggested that C. spirale ND35 could colonize in stems and branches of apple trees successfully, and the ND35 colonization rate of the treatment with solid wheat bran culture was higher than that of corn steep powder broth, but the field experiment result the control effect of liquid culture of C. spirale ND35 was better than that of solid culture.

  20. Production, Purification, and Characterization of a Major Penicillium glabrum Xylanase Using Brewer's Spent Grain as Substrate

    OpenAIRE

    Adriana Knob; Susan Michelz Beitel; Diana Fortkamp; César Rafael Fanchini Terrasan; Alex Fernando de Almeida

    2013-01-01

    In recent decades, xylanases have been used in many processing industries. This study describes the xylanase production by Penicillium glabrum using brewer's spent grain as substrate. Additionally, this is the first work that reports the purification and characterization of a xylanase using this agroindustrial waste. Optimal production was obtained when P. glabrum was grown in liquid medium in pH 5.5, at 25 °C, under stationary condition for six days. The xylanase from P. glabrum was purified...

  1. An evolutionary route to xylanase process fitness

    Science.gov (United States)

    Palackal, Nisha; Brennan, Yali; Callen, Walter N.; Dupree, Paul; Frey, Gerhard; Goubet, Florence; Hazlewood, Geoffrey P.; Healey, Shaun; Kang, Young E.; Kretz, Keith A.; Lee, Edd; Tan, Xuqiu; Tomlinson, Geoffery L.; Verruto, John; Wong, Vicky W.K.; Mathur, Eric J.; Short, Jay M.; Robertson, Dan E.; Steer, Brian A.

    2004-01-01

    Directed evolution technologies were used to selectively improve the stability of an enzyme without compromising its catalytic activity. In particular, this article describes the tandem use of two evolution strategies to evolve a xylanase, rendering it tolerant to temperatures in excess of 90°C. A library of all possible 19 amino acid substitutions at each residue position was generated and screened for activity after a temperature challenge. Nine single amino acid residue changes were identified that enhanced thermostability. All 512 possible combinatorial variants of the nine mutations were then generated and screened for improved thermal tolerance under stringent conditions. The screen yielded eleven variants with substantially improved thermal tolerance. Denaturation temperature transition midpoints were increased from 61°C to as high as 96°C. The use of two evolution strategies in combination enabled the rapid discovery of the enzyme variant with the highest degree of fitness (greater thermal tolerance and activity relative to the wild-type parent). PMID:14718652

  2. Synergistic effects of Bifidobacterium thermophilum RBL67 and selected prebiotics on inhibition of Salmonella colonization in the swine proximal colon PolyFermS model

    OpenAIRE

    Tanner, Sabine Amani; Chassard, Christophe; Zihler Berner, Annina; Lacroix, Christophe

    2014-01-01

    Background Probiotics and prebiotics are promising strategies to counteract Salmonella prevalence in swine. In the present study, we investigated the effects of prebiotics (fructo- (FOS), galacto- (GOS) and mannan- (MOS) oligosaccharides) and the bacteriocinogenic Bifidobacterium thermophilum RBL67 (RBL67) on Salmonella enterica subsp. enterica serovar Typhimurium N-15 (N-15) colonization using the PolyFermS in vitro continuous fermentation model simulating the swine proximal colon. Material ...

  3. Characterization and Purification a Specific Xylanase Showing Arabinofuranosidase Activity from Streptomyces spp. 234P-16

    OpenAIRE

    ALINA AKHDIYA; FAHRRUROZI; TRIO HENDARWIN; ANJA MERYANDINI; DEDEN SAPRUDIN; YULIN LESTARI

    2009-01-01

    Streptomyces spp 234P-16 producing xylanase was isolated from soil sample from Padang, West Sumatra, Indonesia. Crude enzyme (produced by centrifuging the culture at 14000 rpm for about 5 minutes) and purified xylanase have an optimum condition at pH 5 and 90oC. Crude xylanase have half life time of 4 hours, whereas purified xylanase have half life time of 2 ½ hours at 90oC. The molecular mass of purified xylanase was determined to be 42.4 kDa. The Arabinofuranosidase have a Km and Vmax value...

  4. Symbiodinium thermophilum sp. nov., a thermotolerant symbiotic alga prevalent in corals of the world's hottest sea, the Persian/Arabian Gulf.

    Science.gov (United States)

    Hume, B C C; D'Angelo, C; Smith, E G; Stevens, J R; Burt, J; Wiedenmann, J

    2015-01-01

    Coral reefs are in rapid decline on a global scale due to human activities and a changing climate. Shallow water reefs depend on the obligatory symbiosis between the habitat forming coral host and its algal symbiont from the genus Symbiodinium (zooxanthellae). This association is highly sensitive to thermal perturbations and temperatures as little as 1°C above the average summer maxima can cause the breakdown of this symbiosis, termed coral bleaching. Predicting the capacity of corals to survive the expected increase in seawater temperatures depends strongly on our understanding of the thermal tolerance of the symbiotic algae. Here we use molecular phylogenetic analysis of four genetic markers to describe Symbiodinium thermophilum, sp. nov. from the Persian/Arabian Gulf, a thermally tolerant coral symbiont. Phylogenetic inference using the non-coding region of the chloroplast psbA gene resolves S. thermophilum as a monophyletic lineage with large genetic distances from any other ITS2 C3 type found outside the Gulf. Through the characterisation of Symbiodinium associations of 6 species (5 genera) of Gulf corals, we demonstrate that S. thermophilum is the prevalent symbiont all year round in the world's hottest sea, the southern Persian/Arabian Gulf. PMID:25720577

  5. Optimization of alkaline cellulase production by the marine-derived fungus Chaetomium sp. using agricultural and industrial wastes as substrates

    Digital Repository Service at National Institute of Oceanography (India)

    Ravindran, C.; Naveenan, T.; Varatharajan, G.R.

    .0 for exoglucanase (Yazadi et al. 1990). In several other fungi, especially Trichoderma and Aspergillus sp., pH optima are variable but in acidic (3.4–6.3) range (Soni et al. 1999). In conclusion, the results of this study demonstrate that the Chaetomium sp... in case of exo- and endoglucanase, cellobiase in case of β-glucosidase) in 1 min under assay conditions (pH 5.0; 50°C for exo- and endoglucanase, 50°C for β-glucosidase). The released reducing sugar (glucose) was estimated by dinitrosalicylic acid (DNS...

  6. Xynalase Gene Overexpression of Chaetomium cupreum in Pichia pastoris and Immobilization of Enzyme%角毛壳茵木聚糖酶基因xyn24在毕赤酵母中的高效表达及产酶的固定化研究

    Institute of Scientific and Technical Information of China (English)

    王艳君; 杨谦

    2012-01-01

    Based on the gene library of the Chaetomium cupreum mycelium, gene fragments encoding xylanase were obtained after screening, total length of 690bp encoding matureβ-1 ,4-xylanase was got through splicing and RT- PCR amplification. The recombinant methods were used to build the expression vector of xylanase in Pichia pastoris. Recombinant protein was highly expressed under the control of the AOX1 gene promoter and secreted into the medium with molecular weight of about 19.4 ku. The activity was 2.72U/mL in the measurement with chitosan as the sub- strate. SDS and metal ions Mn2+ activated the enzyme. Activity of transformants was stable after 10 generations. Xyla- nase immobilization of the preparation of chitosan micro-spherical and the nature of the free enzyme were compared. The results showed that the optimum pH of the immobilized enzyme shifted to the acidic direction, and the optimum temperature of immobilized enzyme, pH stability and thermal stability were improved.%以生防真菌角毛壳菌(Chaetomium cupreum)菌丝体时期的基因文库为基础,筛选得到编码木聚糖酶基因的片段,经拼接及RT—PCR扩增得到全长590bp的编码β—1,4-木聚糖酶基因序列,利用基因重组的方法构建可在毕赤酵母分泌表达系统中表达的木聚糖酶重组载体,并转化毕赤酵母得到重组子。在毕赤酵母醇氧化酶AOX,基因启动子的作用下,重组蛋白得到高效表达,表达蛋白分泌到培养基中,分子质量约为19.4ku;以水溶性壳聚糖为底物测得酶活为2.72U/mL。SDS及金属离子Mn2+对酶活性具有较强的激活作用;转化子经10代传代培养后酶活性稳定。通过制备的壳聚糖微球对木聚糖酶进行了固定化研究,并与游离酶的性质进行了比较。结果表明:固定化酶的最适pH范围与游离酶相比向酸性方向偏移;固定化酶的最适反应温度、酸碱稳定性及热稳定性均有所提高。

  7. Mycelial glucoamylases produced by the thermophilic fungus Scytalidium thermophilum strains 15.1 and 15.8: purification and biochemical characterization Glucoamilases miceliais produzidas pelas linhagens 15.1 e 15.8 do fungo termofílico Scytalidium thermophilum: purificação e caracterização bioquímica

    Directory of Open Access Journals (Sweden)

    M.S. Ferreira-Nozawa

    2008-06-01

    Full Text Available Two strains (15.1 and 15.8 of the thermophilic fungus Scytalidium thermophilum produced high levels of intracellular glucoamylases, with potential for industrial applications. The isoform I of the glucoamylase produced by 15.1 strain was sequentially submitted to DEAE-Cellulose and CM-Cellulose chromatography, and purified 141-fold, with 5.45% recovery. The glucoamylase of strain 15.8 was purified 71-fold by CM-Cellulose and Concanavalin A-Sepharose chromatography, with 7.38% recovery. Temperature and pH optima were in the range of 50-60ºC and 5.0-6.0, respectively, using starch and maltose as substrates. The glucoamylase of S. thermophilum 15.8 was more stable (t50 > 60 min than that of S. thermophilum 15.1 (t50= 11-15 min, at 60ºC. The glucoamylase activities were enhanced by several ions (e.g. Mn2+ and Ca2+ and inhibited by β-mercaptoethanol. The glucoamylase from 15.1 strain showed a Km of 0.094 mg/ml and 0.029 mg/ml and Vmax of 202 U/mg prot and 109 U/mg prot, for starch and maltose, respectively. The hydrolysis products of starch and maltose, analyzed by TLC, demonstrated glucose as end product and confirming the character of the enzyme as glucoamylase. Differences were observed in relation to the products formed with maltose as substrate between the two strains studied. S. thermophilum 15.8 formed maltotriose in contrast with S. thermophilum 15.1.Duas linhagens (15.1 e 15.8 do fungo termofílico Scytalidium thermophilum se mostraram produtoras de grandes quantidades de glucoamilases, com potencial aplicação industrial. A isoforma I de glucoamilase produzida pela linhagem 15.1 foi submetida seqüencialmente a cromatografia em colunas de DEAE-celulose e CM-celulose, sendo purificada 141 vezes com porcentagem de recuperação de 5,45%. A glucoamilase da linhagem 15.8 foi purificada 71 vezes através do uso de colunas de cromatografia de CM-celulose e Concanavalina A-sepharose com porcentagem de recuperação de 7,38%. Temperatura e pH

  8. Polypeptides having xylanase activity and polynucleotides encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Lopez de Leon, Alfredo; Rey, Michael

    2016-05-31

    The present invention relates to isolated polypeptides having xylanase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  9. Molecular cloning and characterization of multidomain xylanase from manure library

    Science.gov (United States)

    The gene (manf-x10) encoding xylanase from an environmental genomic DNA library was cloned and expressed in Escherichia coli. The encoded enzyme was predicted to be 467 amino acids with a molecular mass of 50.3 kD. The recombinant ManF-X10 was purified by HisTrap affinity column and showed activit...

  10. Visualization of the structural changes in plywood and gypsum board during the growth of Chaetomium globosum and Stachybotrys chartarum

    DEFF Research Database (Denmark)

    Lewinska, Anna Malgorzata; Hoof, Jakob Blæsbjerg; Peuhkuri, Ruut H.;

    2016-01-01

    Fungal growth in indoor environments is associated with many negative health effects. Many studies focus on brown- and white-rot fungi and their effect on wood, but there is none that reveals the influence of soft-rot fungi, such as Stachybotrys spp. and Chaetomium spp., on the structure of build...

  11. Isolation and identification of local Bacillus isolates for xylanase biosynthesis.

    Directory of Open Access Journals (Sweden)

    Hassan Ammoneh

    2014-04-01

    Full Text Available Bacillus species are attractive industrial organisms due to their rapid growth rates leading to a short fermentation cycle and for their capacity to secrete important enzymes and proteins such as xylanase into the extracellular medium. Considering the industrial importance of xylanase, in this current study, Bacillus spp. were isolated from different soils and were screened for their xylanase production.Bacillus isolates used in this study were obtained from a national screening program carried out during 2006-2007 in which soil samples that covered areas throughout the interior of Syria were collected. The prepared inoculum from each of Bacillus isolates was aliquoted onto xylan agar plates, incubated at 30°C for 72 h and screened for xylanase synthesis.Xylanolytic isolates were selected depending on the clear zones of xylan hydrolysis. Fifteen isolates having the highest clearing zone were determined and grown in a solid state fermentation. Of the 15 isolates, three bacilli namely SY30A, SY185C and SY190E that showed maximum xylanase production, were identified using the 16S rDNA sequencing method. According to 16S rDNA gene sequence data, the closest phylogenetic neighbor for SY30A was Bacillus pumilus and for SY185C and SY190E isolates was Bacillus subtilis. Optimal pH and temperature for xylanase activity was 7.0 and 55ºC for SY30A and 6.0 and 60ºC for SY185C and SY190E, respectively. Under these conditions, the following activities were found to be around 1157 ± 58, 916 ± 46 and 794 ± 39 (U/g for SY30A, SY185C and SY190E, respectivly.Selected local Bacillus isolates were found to be a potential source of xylanase which was proven to be quite suitable for multiple biotechnological applications. These isolates might after extensive optimization steps be an alternative to commercially available strains.

  12. A multipurpose immobilized biocatalyst with pectinase, xylanase and cellulase activities

    Directory of Open Access Journals (Sweden)

    Gupta Munishwar

    2007-06-01

    Full Text Available Abstract Background The use of immobilized enzymes for catalyzing various biotransformations is now a widely used approach. In recent years, cross-linked enzyme aggregates (CLEAs have emerged as a novel and versatile biocatalyst design. The present work deals with the preparation of a CLEA from a commercial preparation, Pectinex™ Ultra SP-L, which contains pectinase, xylanase and cellulase activities. The CLEA obtained could be used for any of the enzyme activities. The CLEA was characterized in terms of kinetic parameters, thermal stability and reusability in the context of all the three enzyme activities. Results Complete precipitation of the three enzyme activities was obtained with n-propanol. When resulting precipitates were subjected to cross-linking with 5 mM glutaraldehyde, the three activities initially present (pectinase, xylanase and cellulase were completely retained after cross-linking. The Vmax/Km values were increased from 11, 75 and 16 to 14, 80 and 19 in case of pectinase, xylanase and cellulase activities respectively. The thermal stability was studied at 50°C, 60°C and 70°C for pectinase, xylanase and cellulase respectively. Half-lives were improved from 17, 22 and 32 minutes to 180, 82 and 91 minutes for pectinase, xylanase and cellulase respectively. All three of the enzymes in CLEA could be reused three times without any loss of activity. Conclusion A single multipurpose biocatalyst has been designed which can be used for carrying out three different and independent reactions; 1 hydrolysis of pectin, 2 hydrolysis of xylan and 3 hydrolysis of cellulose. The preparation is more stable at higher temperatures as compared to the free enzymes.

  13. Anti-rheumatoid Activity of Secondary Metabolites Produced by Endophytic Chaetomium globosum

    Science.gov (United States)

    Abdel-Azeem, Ahmed M.; Zaki, Sherif M.; Khalil, Waleed F.; Makhlouf, Noha A.; Farghaly, Lamiaa M.

    2016-01-01

    The aim of the present study was to investigate the anti-rheumatoid activity of secondary metabolites produced by endophytic mycobiota in Egypt. A total of 27 endophytic fungi were isolated from 10 dominant medicinal plant host species in Wadi Tala, Saint Katherine Protectorate, arid Sinai, Egypt. Of those taxa, seven isolates of Chaetomium globosum (CG1–CG7), being the most frequent taxon, were recovered from seven different host plants and screened for production of active anti-inflammatory metabolites. Isolates were cultivated on half – strength potato dextrose broth for 21 days at 28°C on a rotatory shaker at 180 rpm, and extracted in ethyl acetate and methanol, respectively. The probable inhibitory effects of both extracts against an adjuvant induced arthritis (AIA) rat model were examined and compared with the effects of methotrexate (MTX) as a standard disease-modifying anti-rheumatoid drug. Disease activity and mobility scoring of AIA, histopathology and transmission electron microscopy (TEM) were used to evaluate probable inhibitory roles. A significant reduction (P < 0.05) in the severity of arthritis was observed in both the methanolic extract of CG6 (MCG6) and MTX treatment groups 6 days after treatment commenced. The average arthritis score of the MCG6 treatment group was (10.7 ± 0.82) compared to (13.8 ± 0.98) in the positive control group. The mobility score of the MCG6 treatment group (1.50 ± 0.55) was significantly lower than that of the positive control group (3.33 ± 0.82). In contrast, the ethyl acetate extract of CG6 (EACG6) treatment group showed no improvements in arthritis and mobility scores in AIA model rats. Histopathology and TEM findings confirmed the observation. Isolate CG6 was subjected to sequencing for confirmation of phenotypic identification. The internal transcribed spacer (ITS) 1–5.8 s – ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number KC

  14. The xylanase inhibitor TAXI-III counteracts the necrotic activity of a Fusarium graminearum xylanase in vitro and in durum wheat transgenic plants.

    Science.gov (United States)

    Moscetti, Ilaria; Faoro, Franco; Moro, Stefano; Sabbadin, Davide; Sella, Luca; Favaron, Francesco; D'Ovidio, Renato

    2015-08-01

    The xylanase inhibitor TAXI-III has been proven to delay Fusarium head blight (FHB) symptoms caused by Fusarium graminearum in transgenic durum wheat plants. To elucidate the molecular mechanism underlying the capacity of the TAXI-III transgenic plants to limit FHB symptoms, we treated wheat tissues with the xylanase FGSG_03624, hitherto shown to induce cell death and hydrogen peroxide accumulation. Experiments performed on lemmas of flowering wheat spikes and wheat cell suspension cultures demonstrated that pre-incubation of xylanase FGSG_03624 with TAXI-III significantly decreased cell death. Most interestingly, a reduced cell death relative to control non-transgenic plants was also obtained by treating, with the same xylanase, lemmas of TAXI-III transgenic plants. Molecular modelling studies predicted an interaction between the TAXI-III residue H395 and residues E122 and E214 belonging to the active site of xylanase FGSG_03624. These results provide, for the first time, clear indications in vitro and in planta that a xylanase inhibitor can prevent the necrotic activity of a xylanase, and suggest that the reduced FHB symptoms on transgenic TAXI-III plants may be a result not only of the direct inhibition of xylanase activity secreted by the pathogen, but also of the capacity of TAXI-III to avoid host cell death.

  15. Characterization of two truncated forms of xylanase recombinantly expressed by Lactobacillus reuteri with an introduced rumen fungal xylanase gene.

    Science.gov (United States)

    Cheng, Hsueh-Ling; Hu, Chun-Yi; Lin, Shiou-Hua; Wang, Jing-Ya; Liu, Je-Ruei; Chen, Yo-Chia

    2014-10-01

    The xylanase R8 gene (xynR8) from uncultured rumen fungi was cloned and successfully expressed in Lactobacillus reuteri. A xylanase activity of 132.1 U/mL was found in the broth of L. reuteri R8, the transformant containing pNZ3004 vector with xynR8 gene insertion. Two distinct forms of recombinant xylanase with different hydrophobicities and molecular weights were found in the broth after purification. According to the results of Western blotting, only the T7-tag, fused in the N-terminus of XynR8, could be bound to the expressed proteins, which indicated that the C-terminus of XynR8 had been truncated. These results, combined with tryptic digestion and mass spectrometry analyses, allow us to attribute the two xylanase forms to an optional cleavage of C-terminal sequences, and XynR8A, a 13 amino acid residues truncated form, and XynR8B, a 22 amino acid residues truncated form, were the main products in the extracellular fraction of L. reuteri R8. The specific activities of XynR8A and R8B were 1028 and 395 U/mg protein. Both forms of recombinant xylanase displayed a typical endoxylanase activity when they were reacted with xylan, but XynR8A demonstrated a better specific activity, catalytic efficiency and thermostability than XynR8B according to the results of enzyme characterization. These changes in enzyme properties were highly possibly caused by the present of the β-sheet in the C-terminal undeleted fragment of XynR8A. This study demonstrates that modified forms with different enzyme properties could be produced when a gene was recombinantly expressed by a L. reuteri transformant. PMID:25152410

  16. Scytalidium thermophilum-colonized grain, corncobs and chopped wheat straw substrates for the production of Agaricus bisporus.

    Science.gov (United States)

    Sanchez, Jose E; Royse, Daniel J

    2009-02-01

    We examined the possibility of cultivating Agaricus bisporus (Ab) on various grains and agricultural by-products, with the objective of improving yield capacity of substrate pre-colonized by Scytalidium thermophilum (St). Radial growth rate (RGR) of St at 45 degrees C ranged from no growth on sterile wheat grain to 14.9 mm/d on whole oats. The linear extension rate (LER) of Ab, grown on St-colonized substrate (4 days at 45 degrees C), ranged from a low of 2.7 mm/d on 100% corncobs to 4.7 mm/d on a 50/50 mixture of ground corncobs/millet grain. Several other substrates containing wheat straw+ground corncobs+boiled millet and pre-colonized by St (4 days at 42+/-3 degrees C), were evaluated for production of Ab. The biological efficiency (BE) of production increased linearly with the addition of millet to the formula. However, substrates with millet levels 84% often were contaminated before mushroom harvest. Maximum BE (99%) and yield (21.6 kg/m(2)) were obtained on St-colonized wheat straw+2% hydrated lime supplemented with 9% commercial supplement added both at spawning and at casing. PMID:18954978

  17. OPTIMIZATION OF XYLANASE PRODUCTION FROM FREE AND IMMOBILIZED CELLS OF FUSARIUM SOLANI F7

    OpenAIRE

    Vijai Kumar Gupta; Rajeeva Gaur; Santosh Kumar Yadava; Nandan Singh Darmwal

    2009-01-01

    The aim of the present investigation was to characterize a xylanase-producing Fusarium solani isolate and to optimize cultural conditions for xylanase enzyme production from free and immobilized cells. Screening of Fusarium solani isolate was based on the diameter of the clear zone formation in oat spelt xylan agar plates. Fusarium solani isolate F7 was selected and optimized for xylanase enzyme production using cheaper substrates such as wheat straw, rice straw, rice bran, and wood husk. Max...

  18. Xylanase production with xylan rich lignocellulosic wastes by a local soil isolate of Trichoderma viride

    OpenAIRE

    Goyal, Meenakshi; Kalra, K. L.; V.K. Sareen; G. Soni

    2008-01-01

    In the present study, cultural and nutritional conditions for enhanced production of xylanase by a local soil isolate of Trichoderma viride, using various lignocellulosic substrates in submerged culture fermentation have been optimized. Of the lignocellulosics used, maize straw was the best inducer followed by jowar straw for xylanase production. The highest activity achieved was between 14 to 17 days of fermentation. A continuous increase in xylanase production was observed with increasing l...

  19. Purification and some properties of an alkaline xylanase from alkaliphilic Bacillus sp. strain 41M-1.

    OpenAIRE

    Nakamura, S.; Wakabayashi, K; Nakai, R; Aono, R; Horikoshi, K

    1993-01-01

    An alkaliphilic Bacillus sp. strain, 41M-1, isolated from soil produced multiple xylanases extracellularly. One of these xylanases was purified to homogeneity by ammonium sulfate fractionation and anion-exchange chromatography. The moleculr mass of this enzyme (xylanase J) was 36 kDa, and the isoelectric point was pH 5.3. Xylanase J was most active at pH 9.0. The optimum temperature for the activity at pH 9.0 was around 50 degrees C. The enzyme was stable up to 55 degrees C at pH 9.0 for 30 m...

  20. THE INFLUENCE OF XYLANASE ON THE QUALITY OF BREAD

    Directory of Open Access Journals (Sweden)

    RODICA CHEREJI

    2013-12-01

    Full Text Available This paper determined the quality of the bread obtained form the control flour (M and the quality of the bread obtained from the flour with an addition of 3 different concentrations of xylanase (P1-8100 U.FXU/ 100 kg flour, P2-16200 U.FXU/ 100 kg flour, P3-24300 U.FXU/ 100 kg flour. Xylanase was used in these concentrations to establish which one is more suitable to be added in flour to obtain superior quality characteristics of the bread: higher volume, fine texture of the core, prolonging the freshness of the bread, improving the color and flavor of the bread, improving the cutting proprieties of the bread.

  1. Thermostable Xylanases of Microbial Origin: Recent Insights and Biotechnological Potential

    OpenAIRE

    S.S. Kanwar; Sunita Devi

    2012-01-01

    Xylanases are hydrolases which depolymerise the plant cell wall component-xylan, the second most abundant polysaccharide. They are mainly produced by microorganisms but can also be found in plants, marine algae, protozoans, crustaceans, insects, and snails. Because of their ability to break down xylan, these enzymes especially of microbial origin, have attracted more attention due to their potential role in pulping and bleaching processes, in food and feed industry, textile processes and orga...

  2. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans

    NARCIS (Netherlands)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-01-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity af

  3. A multipurpose immobilized biocatalyst with pectinase, xylanase and cellulase activities

    OpenAIRE

    Gupta Munishwar; Sharma Aparna; Dalal Sohel

    2007-01-01

    Abstract Background The use of immobilized enzymes for catalyzing various biotransformations is now a widely used approach. In recent years, cross-linked enzyme aggregates (CLEAs) have emerged as a novel and versatile biocatalyst design. The present work deals with the preparation of a CLEA from a commercial preparation, Pectinex™ Ultra SP-L, which contains pectinase, xylanase and cellulase activities. The CLEA obtained could be used for any of the enzyme activities. The CLEA was characterize...

  4. Fusarium graminearum produces different xylanases causing host cell death that is prevented by the xylanase inhibitors XIP-I and TAXI-III in wheat.

    Science.gov (United States)

    Tundo, Silvio; Moscetti, Ilaria; Faoro, Franco; Lafond, Mickaël; Giardina, Thierry; Favaron, Francesco; Sella, Luca; D'Ovidio, Renato

    2015-11-01

    To shed light on the role of Xylanase Inhibitors (XIs) during Fusarium graminearum infection, we first demonstrated that three out of four F. graminearum xylanases, in addition to their xylan degrading activity, have also the capacity to cause host cell death both in cell suspensions and wheat spike tissue. Subsequently, we demonstrated that TAXI-III and XIP-I prevented both the enzyme and host cell death activities of F. graminearum xylanases. In particular, we showed that the enzymatic inhibition by TAXI-III and XIP-I was competitive and only FGSG_11487 escaped inhibition. The finding that TAXI-III and XIP-I prevented cell death activity of heat inactivated xylanases and that XIP-I precluded the cell death activity of FGSG_11487 - even if XIP-I does not inhibit its enzyme activity - suggests that the catalytic and the cell death activities are separated features of these xylanases. Finally, the efficacy of TAXI-III or XIP-I to prevent host cell death caused by xylanases was confirmed in transgenic plants expressing separately these inhibitors, suggesting that the XIs could limit F. graminearum infection via direct inhibition of xylanase activity and/or by preventing host cell death.

  5. Isolation, purification and characterization of xylanase produced by Arthrobacter sp. MTCC 5214 when grown in solid-state fermentation

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    Thermoalkalophilic Arthrobacter sp. produced extracellular xylanase, when wheat bran, rice husk, rice bran and bagassae were used as carbon source under solid-state fermentation (SSF). The xylanase enzyme was isolated by ammonium sulfate (80...

  6. Polyethyleneimine as a promoter layer for the immobilization of cellobiose dehydrogenase from Myriococcum thermophilum on graphite electrodes.

    Science.gov (United States)

    Schulz, Christopher; Ludwig, Roland; Gorton, Lo

    2014-05-01

    Cellobiose dehydrogenase (CDH) is a promising enzyme for the construction of biofuel cell anodes and biosensors capable of oxidizing aldoses as cellobiose as well as lactose and glucose and with the ability to connect to an electrode through a direct electron transfer mechanism. In the present study, we point out the beneficial effect of a premodification of spectrographic graphite electrodes with the polycation polyethyleneimine (PEI) prior to adsorption of CDH from Myriococcum thermophilum (MtCDH). The application of PEI shifts the pH optimum of the response of the MtCDH modified electrode from pH 5.5 to 8. The catalytic currents to lactose were increased up to 140 times, and the K(M)(app) values were increased up to 9 times. The previously investigated, beneficial effect of divalent cations on the activity of CDH was also present for graphite/PEI/MtCDH electrodes but was less pronounced. Polarization curves revealed a second unexpected catalytic wave for graphite/PEI/MtCDH electrodes especially pronounced at pH 8. Square wave voltammetric studies revealed the presence of an unknown redox functionality present at 192 mV vs Ag|AgCl (0.1 M KCl) at pH 8, probably originating from an oxidized adenosine derivative. Adenosine is a structural part of the flavin adenine dinucleotide (FAD) cofactor of the dehydrogenase domain of CDH. It is suggested that for some enzyme molecules FAD leaks out from the active site, adsorbs onto graphite, and is oxidized on the electrode surface into a product able to mediate the electron transfer between CDH and the electrode. PEI is suggested and discussed to act in several manners by (a) increasing the surface loading of the enzyme, (b) possibly increasing the electron transfer rate between CDH and the electrode, and (c) facilitating the creation or immobilization of redox active adenosine derivatives able to additionally mediate the electron transfer between CDH and the electrode.

  7. A novel halotolerant xylanase from marine isolate Bacillus subtilis cho40: gene cloning and sequencing

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Verma, P.; Deobagkar, D.

    induced (140%) when pre-incubated with 0.5 M NaCl for 4 h. The xylanase gene, xyn40, from marine bacterium B. subtilis cho40 was cloned, and expressed in Escherichia coli. The xylanase gene was 645 bp long and had a 215 amino acid ORF protein with a...

  8. Purification and characterization of a GH11 xylanase from biobutanol-producing Clostridium beijerinckii G117.

    Science.gov (United States)

    Ng, Choong Hey; He, Jianzhong; Yang, Kun-Lin

    2015-03-01

    Most biobutanol-producing Clostridium strains are unable to ferment polysaccharides such as cellulose and xylan due to the lack of hydrolyzing enzymes. In this study, we show that Clostridium beijerinckii G117, a newly isolated biobutanol-producing strain, expresses xylanase enzyme in the presence of 1% beechwood xylan. The xylanase activity in the medium containing actively growing culture and 1% of beechwood xylan can reach up to 2.66 U/ml after 14 h of fermentation. Using salting-out and size-exclusion chromatography, we purify the crude xylanase by 8.7-fold from the supernatant with a yield of 32.2%. This purified xylanase has a molecular weight of 22.6 kDa, making it one of the smallest reported clostridial xylanases. Conserved domain analysis reveals that the xylanase belongs to glycoside hydrolase family 11 (GH11) but lacks a carbohydrate binding domain. When beechwood xylan is used as substrate for the xylanase, majority of the products are xylo-oligosaccharide (~98%), suggesting that this is an endo-1,4-β-xylanase. PMID:25564206

  9. OPTIMIZATION OF XYLANASE PRODUCTION FROM FREE AND IMMOBILIZED CELLS OF FUSARIUM SOLANI F7

    Directory of Open Access Journals (Sweden)

    Vijai Kumar Gupta

    2009-08-01

    Full Text Available The aim of the present investigation was to characterize a xylanase-producing Fusarium solani isolate and to optimize cultural conditions for xylanase enzyme production from free and immobilized cells. Screening of Fusarium solani isolate was based on the diameter of the clear zone formation in oat spelt xylan agar plates. Fusarium solani isolate F7 was selected and optimized for xylanase enzyme production using cheaper substrates such as wheat straw, rice straw, rice bran, and wood husk. Maximum enzyme activity was observed in wheat straw (78.32 U ml-1 for free cells and 94.68 U ml-1 for immobilized cells. Optimum pH and temperature for xylanase activity were found to be 5.5 and 30°C at 3% substrate concentration for free cells and 5.0 and 30°C at 3% substrate concentration for immobilized cells. In the purification step, 75% ammonium sulphate saturation was found to be suitable, giving maximum xylanase activity. Production of xylanase was greater from immobilized cells than from free cells. Purified xylanase from free cells yielded a single band with a molecular weight of 89kDa, while it was 92.8kDa for immobilized cells. The use of wheat straw as a major carbon source is particularly valuable, because oat spelt xylan is very expensive. The Fusarium solani F7 isolate proved to be a promising microorganism for xylanase production.

  10. Cloning, sequencing and expression of a xylanase gene from the maize pathogen Helminthosporium turcicum

    DEFF Research Database (Denmark)

    Degefu, Y.; Paulin, L.; Lübeck, Peter Stephensen

    2001-01-01

    A gene encoding an endoxylanase from the phytopathogenic fungus Helminthosporium turcicum Pass. was cloned and sequenced. The entire nucleotide sequence of a 1991 bp genomic fragment containing an endoxylanase gene was determined. The xylanase gene of 795 bp, interrupted by two introns of 52 and ...... xylan as a sole carbon source. The cloned xylanase gene was expressed in maize plants during infection....

  11. Performance and morphometry of the intestinal mucosa of laying hens fed diets containing xylanase

    Directory of Open Access Journals (Sweden)

    KMR de Souza

    2014-09-01

    Full Text Available The objective of this study was to evaluate the effect of dietary energy level reduction and xylanase inclusion on the performance and on intestinal mucosa morphometry of two- to six-week-old laying hens. In total, 400 Hy-line W36 laying hens were distributed according to a completely randomized design in 2 x 2 factorial arrangement (energy level x inclusion of xylanase, totaling four treatments with 10 replicates of 10 birds per experimental unit. The following treatments were evaluated: positive control (balanced diet; positive control + xylanase; negative control (diet with of 100 kcal ME reduction /kg; negative control + xylanase. Body weight, weight gain, feed conversion ratio, uniformity and livability were not influenced by diets with metabolizable energy reduction and xylanase inclusion; however, the addition of xylanase to the diets resulted in shallower crypts depth and greater villus:crypt ratio in the ileum. The energy reduction of the diet associated with the supplementation of xylanase did not influence performance, but increased the feed intake of 2- to 6-week-old laying hens and increased villus height in the ileum of 6-wk-old hens. Xylanase reduces crypt depth in the ileum of 6-week-old hens.

  12. Failure of the sterile air-flow component of a protected environment detected by demonstration of Chaetomium species colonization of four consecutive immunosuppressed occupants.

    Science.gov (United States)

    Woods, G L; Davis, J C; Vaughan, W P

    1988-10-01

    Four bone marrow transplant recipients consecutively occupying the same room on our Oncology-Hematology Special Care Unit (OHSCU) became colonized with Chaetomium species between January and April, 1987. These patients, aged 27 to 43 years, were immunocompromised as a result of intensive chemotherapy, and were consequently at increased risk for development of invasive fungal infection. At the time of Chaetomium colonization, all patients were febrile, two had transient new infiltrates on chest x-ray, and three were receiving amphotericin B therapy. Subsequent environmental cultures revealed Chaetomium contamination of the OHSCU air-handling system, including the HEPA (high-efficiency particulate air) filters in seven of the nine rooms comprising the unit. Because fungal colonization of HEPA filters used to create a "protective environment" for immunocompromised patients can occur and can serve as a source for patient infections, guidelines concerning proper surveillance of these HEPA filters should be established. We suggest that before a new patient enters a "protected" room, the clean side of the HEPA filter should be cultured. If fungi are recovered from that culture, we would recommend changing the filter. PMID:3066822

  13. Characterization and Purification a Specific Xylanase Showing Arabinofuranosidase Activity from Streptomyces spp. 234P-16

    Directory of Open Access Journals (Sweden)

    ALINA AKHDIYA

    2009-07-01

    Full Text Available Streptomyces spp 234P-16 producing xylanase was isolated from soil sample from Padang, West Sumatra, Indonesia. Crude enzyme (produced by centrifuging the culture at 14000 rpm for about 5 minutes and purified xylanase have an optimum condition at pH 5 and 90oC. Crude xylanase have half life time of 4 hours, whereas purified xylanase have half life time of 2 ½ hours at 90oC. The molecular mass of purified xylanase was determined to be 42.4 kDa. The Arabinofuranosidase have a Km and Vmax value of 1,98 mg/mL and 523 µmol/minute/mg, respectively.

  14. [Cellulase and xylanase activity of phytopathogenic and endophytic fungal strains of Alternaria alternata (Fr.) Keissler].

    Science.gov (United States)

    Kurchenko, I M; Sokolova, O V; Zhdanova, N M; Iarynchyn, A M; Iovenko, O M

    2008-01-01

    A comparative analysis of cellulase and xylanase activity of 25 fungal strains of phytopathogenic and endophytic Alternaria alternata had been realized for the first time using the qualitative reactions. The rate of their linear growth on the media with carboxymethylcellulose or xylane had been studied. The cellulase and xylanase activities clearly depended on the distinct strain. The absence of distinct dependence of cellulase and xylanase activities on the species and organs of host plants was demonstrated. The majority of investigated strains of A. alternata did not possess a cellulase activity or the latter was low, but as a whole the phytopathogenic strains were more active than endophytic ones. Xylanase activity was considerable for the fungal strains of all trophyc groups. It was shown that the level of xylanase activity cannot become a biochemical marker of the A. alternata isolate pathogenicity.

  15. Isolation and Identification of the Metabolites Produced by Endophytic Fungus Chaetomium globosum ZY-22 from Ginkgo biloba%银杏内生菌Chaetomium globosum ZY-22次生代谢产物分离鉴定

    Institute of Scientific and Technical Information of China (English)

    秦建春; 白莉; 李晓明; 张雅梅; 高锦明; Hartmut laatsch

    2009-01-01

    Six metabolites cerebroside B (1),cerebroside C (2),allantoin (3),9(11)-dehyoergosterol peroxide (4) and ergosta-4,6,8,22-tetraen-3-one (5),chaetoglobosin A (6) were isolated by column chromatography from the extract of cultural mycelium of fungus Chaetomium globosum ZY-22,an endophyte in the leaves of Ginkgo biloba.Structures of them were established by spectroscopic methods.Among of them,cerebroside B,cerebroside C,allantoin were firstly obtained from endophytic fungus;The result of brine shrimp bioassay showed the mortality rates of them to Artemia salina are 1.6%,4.2%,7.4%,16.9%,12.8% and 83.6% respectively at the concentration of 10 μg/mL,chaetoglobosin A showed significant toxic effect on brine shrimp.%采用柱层析方法从银杏叶内生真菌Chaetomium globosum ZY-22的培养菌丝体提取物中分离得到脑苷脂B(1)、脑苷脂C(2)、尿囊素(3)、9(11)-去氢麦角甾醇过氧化物(4)以及4,6,8,22-四烯-3-酮-麦角甾烷(5)和球毛壳甲素(6)共6个次生代谢物;经波谱分析确定了6个化合物的结构,其中脑苷脂B、脑苷脂C和尿囊素是首次从内生真菌中得到;海虾致死试验结果显示,化合物1~6在10 μg/mL浓度下对丰年虾的致死率分别为1.6%、4.2%、7.4%、16.9%、12.8%、83.6%、表明球毛壳甲素对海虾表现出很强的毒性作用.

  16. Kinetics of Xylanase Fermentation by Recombinant Escherichia coli DH5α in Shake Flask Culture

    Directory of Open Access Journals (Sweden)

    Farliahati Mohd Rusli

    2009-01-01

    Full Text Available Problem statement: Interest in xylanase enzyme application has markedly increased in pulp and paper processing industries. The switch to xylanase-producing recombinant Escherichia coli DH5α pTP510 is seen here as an economic alternative towards higher productivity and easier downstream purification. Modeling of E. coli DH5α growth and enzyme secretion is thus desired for future optimization in fermentation process. Approach: Kinetics of intracellular xylanase fermentation by a recombinant E. coli DH5α was studied in shake flask culture. The effect of different medium formulations (complex, minimal and defined, initial pH (6.5, 7.0, 7.4 and 8.0 and agitation speeds (150, 200 and 250 rpm on cell growth and xylanase production were evaluated. Mathematical models based on Logistic and Luedeking-Piret equations had been proposed to describe the microbial growth and xylanase production. Results: Highest xylanase production was obtained in defined medium. Based on medium formulation, the highest cell concentration (4.59 g L-1 and xylanase production (2, 122.5 U mL-1 was obtained when (NH42HPO4 was used as the main nitrogen source, with an adjustment of the initial pH to 7.4 and agitation speed of 200 rpm. The maximum specific growth rate (µmax, growth associated xylanase production coefficient (α and non-growth associated xylanase production coefficient (β was 0.41 h-1, 474.26 U mg cell-1 and 0 U mg cell-1 h-1, respectively. Conclusion: Xylanase production was growth associated process and the enzyme secretion was greatly dependent on cell concentration and the specific growth rate of E. coli DH5α.

  17. Bifunctional xylanases and their potential use in biotechnology

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Numan, M.Th.

    showed signiWcant similarity (33– 40% identical residues) to a diVerent group of bacterial xylanases and exoglucanases exempliWed by the Caldocel- lum saccharolyticum xynA and celB products. The xynA product is, therefore, a bifunctional enzyme having two... biochemistry of fungal and bacterial cellulolytic enzyme system. In: Aubert JP, Be- guin P, Millet J (eds) Biochemistry and genetics of cellulose deg- radation. Academic Press, London, pp 11–30 19. Cui W, Wood PJ, Blackwell B, Nikiforuk J (2000) Physicochemi...

  18. Partial purification and characterization of xylanase produced by Penicillium expansum

    Directory of Open Access Journals (Sweden)

    André Luiz de Souza Querido

    2006-05-01

    Full Text Available An extracellular xylanase was found to be the major protein in the filtrate culture of Penicillium expansum when grown on 0.3 % wheat bran, which showed no xylanase multiplicity. The enzime was partial purified by.ammonium sulfate fractioning, molecular exclusion chromatography, ultrafiltration and anion exchange chromatography. The protein eluation profile showed only one form of xylanase that was partially characterized. The activity of purified xylanase was optimal at pH 5.5 and 40 ºC. The enzyme was stable at pH between 5.5 and 6.5 and temperatures between 20-40 ºC. The enzyme showed a Km of 3.03 mM and Vmax of 0.027 mumol min-1 mug -1 of protein. The enzymatic activity was increased 31 % by Mg2+ and 28 % by Al3+.Uma xilanase extracelular foi encontrada como a principal proteína na cultura filtrada de Penicillium expansum quando cultivado em farelo de trigo 0,3 %, a qual não mostrou multiplicidade. A enzima foi parcialmente purificada por fracionamento com sulfato de amônia, cromatografia de exclusão molecular, ultrafiltração e cromatografia de troca aniônica. O perfil de eluição das proteínas mostrou uma única forma de xilanase, sendo esta parcialmente caracterizada. A atividade da xilanase purificada foi ótima em pH 5.5 e à temperatura de 40 ºC. A enzima foi estável em pH entre 5,5 e 6,5 e à temperatura entre 20-40ºC. A enzima apresentou Km de 3,03 mM e Vmax de 0,027 mimol min-1 mig-1 de proteína. A atividade enzimática foi aumentada 31 % por Mg+2 e 28 % por Al+3.

  19. Novel thermostable endo-xylanase cloned and expressed from bacterium Geobacillus sp. WSUCF1.

    Science.gov (United States)

    Bhalla, Aditya; Bischoff, Kenneth M; Uppugundla, Nirmal; Balan, Venkatesh; Sani, Rajesh K

    2014-08-01

    A gene encoding a GH10 endo-xylanase from Geobacillus sp. WSUCF1 was cloned and expressed in Escherichia coli. Recombinant endo-xylanase (37kDa) exhibited high specific activity of 461.0U/mg of protein. Endo-xylanase was optimally active on birchwood xylan at 70°C and pH 6.5. The endo-xylanase was found to be highly thermostable at 50 and 60°C, retaining 82% and 50% of its original activity, respectively, after 60h. High xylan conversions (92%) were obtained with oat-spelt xylan hydrolysis. Higher glucan and xylan conversions were obtained on AFEX-treated corn stover with an enzyme cocktail containing WSUCF1 endo-xylanase (71% and 47%) as compared to enzyme cocktail containing commercial fungal endo-xylanase (64% and 41%). High specific activity, active at high pH's, wide substrate specificity, and higher hydrolytic activity on recalcitrant lignocellulose, make this endo-xylanase a suitable candidate for biofuel and bioprocess industries.

  20. Synergistic effect and application of xylanases as accessory enzymes to enhance the hydrolysis of pretreated bagasse.

    Science.gov (United States)

    Gonçalves, Geisa A L; Takasugi, Yusaku; Jia, Lili; Mori, Yutaro; Noda, Shuhei; Tanaka, Tsutomu; Ichinose, Hirofumi; Kamiya, Noriho

    2015-05-01

    Recently, the new trend in the second-generation ethanol industry is to use mild pretreatments, in order to reduce costs and to keep higher content of hemicellulose in the biomass. Nevertheless, a high enzyme dosage is still required in the conversion of (hemi)cellulose. The interaction between cellulases and xylanases seems to be an effective alternative to reduce enzyme loading in the saccharification process. At first, to evaluate the synergism of xylanases on bagasse degradation, we have produced two xylanases from glycoside hydrolase family 10 (GH10) and three xylanases from glycoside hydrolase family 11 (GH11), from two thermophilic organisms, Thermobifida fusca and Clostridium thermocellum, and one mesophilic organism, Streptomyces lividans. Peracetic acid (PAA) pretreated bagasse was used as substrate. The combination of XynZ-C (GH10, from C. thermocellum), and XlnB (GH11, from S. lividans) presented the highest degree of synergy after 6h (3.62). However, the combination of XynZ-C and Xyn11A (GH11, from T. fusca) resulted in the highest total yield of reducing sugars. To evaluate the synergism between xylanases and cellulases, commercial cellulase preparation from Trichoderma reesei was combined with the selected xylanases, XynZ-C and Xyn11A. About 2-fold increase was observed in the concentration of reducing sugars, when both xylanases, XynZ-C and Xyn11A, were added together with T. reesei cellulases in the reaction mixture.

  1. Molecular characterization of a Xylanase-producing fungus isolated from fouled soil

    Directory of Open Access Journals (Sweden)

    Punniavan Sakthiselvan

    2014-12-01

    Full Text Available Xylanase (EC 3. 2. 1. 8, hydrolyzes xylo-oligosaccharides into D-xylose and required for complete hydrolysis of native cellulose and biomass conversion. It has broad range of applications in the pulp and paper, pharmaceutical and Agri-food industries. Fifty fungal species were isolated from the fouled soil around an oil refinery and screened for the production of xylanase enzyme by enrichment culture techniques. The isolated fungal strain was identified as Hypocrea lixii SS1 based on the results of biochemical tests and 18s rRNA sequencing. The phylogenetic tree was constructed using the MEGA 5 software. Further, Hypocrea lixii SS1 was tested for the ability to utilize the sunflower oil sludge (waste from the oil industry as the sole carbon source for xylanase production. The growth characteristics of Hypocrea lixii SS1 were also studied and maximum growth was found on the 7th day of incubation. The fungus showed a remarkable xylanase production of 38.9 U/mL. Xylanase was purified using a combination of 0-50% NH4SO2 precipitation, DEAE-sepharose and Sephacryl S-200 chromatography. Single peak obtained in RP-HPLC confirms the purity of xylanase. Further the enzyme produced was affirmed as xylanase with its molecular weight (29 kDa using SDS-PAGE.

  2. Molecular characterization of a Xylanase-producing fungus isolated from fouled soil.

    Science.gov (United States)

    Sakthiselvan, Punniavan; Naveena, Balakrishnan; Partha, Nagarajan

    2014-01-01

    Xylanase (EC 3. 2. 1. 8), hydrolyzes xylo-oligosaccharides into D-xylose and required for complete hydrolysis of native cellulose and biomass conversion. It has broad range of applications in the pulp and paper, pharmaceutical and Agri-food industries. Fifty fungal species were isolated from the fouled soil around an oil refinery and screened for the production of xylanase enzyme by enrichment culture techniques. The isolated fungal strain was identified as Hypocrea lixii SS1 based on the results of biochemical tests and 18s rRNA sequencing. The phylogenetic tree was constructed using the MEGA 5 software. Further, Hypocrea lixii SS1 was tested for the ability to utilize the sunflower oil sludge (waste from the oil industry) as the sole carbon source for xylanase production. The growth characteristics of Hypocrea lixii SS1 were also studied and maximum growth was found on the 7(th) day of incubation. The fungus showed a remarkable xylanase production of 38.9 U/mL. Xylanase was purified using a combination of 0-50% NH₄SO₂ precipitation, DEAE-sepharose and Sephacryl S-200 chromatography. Single peak obtained in RP-HPLC confirms the purity of xylanase. Further the enzyme produced was affirmed as xylanase with its molecular weight (29 kDa) using SDS-PAGE.

  3. Production, Purification, and Characterization of a Major Penicillium glabrum Xylanase Using Brewer's Spent Grain as Substrate

    Directory of Open Access Journals (Sweden)

    Adriana Knob

    2013-01-01

    Full Text Available In recent decades, xylanases have been used in many processing industries. This study describes the xylanase production by Penicillium glabrum using brewer's spent grain as substrate. Additionally, this is the first work that reports the purification and characterization of a xylanase using this agroindustrial waste. Optimal production was obtained when P. glabrum was grown in liquid medium in pH 5.5, at 25 °C, under stationary condition for six days. The xylanase from P. glabrum was purified to homogeneity by a rapid and inexpensive procedure, using ammonium sulfate fractionation and molecular exclusion chromatography. SDS-PAGE analysis revealed one band with estimated molecular mass of 18.36 kDa. The optimum activity was observed at 60 °C, in pH 3.0. The enzyme was very stable at 50 °C, and high pH stability was verified from pH 2.5 to 5.0. The ion Mn2+ and the reducing agents β-mercaptoethanol and DTT enhanced xylanase activity, while the ions Hg2+, Zn2+, and Cu2+ as well as the detergent SDS were strong inhibitors of the enzyme. The use of brewer's spent grain as substrate for xylanase production cannot only add value and decrease the amount of this waste but also reduce the xylanase production cost.

  4. Production and Partial Characterization of an Alkaline Xylanase from a Novel Fungus Cladosporium oxysporum

    Directory of Open Access Journals (Sweden)

    Guo-Qiang Guan

    2016-01-01

    Full Text Available A new fungus Cladosporium oxysporum GQ-3 producing extracellular xylanase was isolated from decaying agricultural waste and identified based on the morphology and comparison of internal transcribed spacer (ITS rDNA gene sequence. C. oxysporum produced maximum xylanase activity of 55.92 U/mL with wheat bran as a substrate and NH4Cl as a nitrogen source. Mg2+ improved C. oxysporum xylanase production. Partially purified xylanase exhibited maximum activity at 50°C and pH 8.0, respectively, and showed the stable activity after 2-h treatment in pH 7.0–8.5 or below 55°C. Mg2+ enhanced the xylanase activity by 2% while Cu2+ had the highest inhibition ratio of 57.9%. Furthermore, C. oxysporum xylanase was resistant to most of tested neutral and alkaline proteases. Our findings indicated that Cladosporium oxysporum GQ-3 was a novel xylanase producer, which could be used in the textile processes or paper/feed industries.

  5. Highly thermostable xylanase production from a thermophilic Geobacillus sp. strain WSUCF1 utilizing lignocellulosic biomass

    Directory of Open Access Journals (Sweden)

    Aditya eBhalla

    2015-06-01

    Full Text Available AbstractEfficient enzymatic hydrolysis of lignocellulose to fermentable sugars requires a complete repertoire of biomass deconstruction enzymes. Hemicellulases play an important role in hydrolyzing hemicellulose component of lignocellulose to xylo-oligosaccharides and xylose. Thermostable xylanases have been a focus of attention as industrially important enzymes due to their long shelf life at high temperatures. Geobacillus sp. strain WSUCF1 produced thermostable xylanase activity (crude xylanase cocktail when grown on xylan or various inexpensive untreated and pretreated lignocellulosic biomasses such as prairie cord grass and corn stover. The optimum pH and temperature for the crude xylanase cocktail were 6.5 and 70ºC, respectively. The WSUCF1 crude xylanase was found to be highly thermostable with half-lives of 18 and 12 days at 60 and 70ºC, respectively. At 70ºC, rates of xylan hydrolysis were also found to be better with the WSUCF1 secretome than those with commercial enzymes, i.e., for WSUCF1 crude xylanase, CellicHTec2, and AccelleraseXY, the percent xylan conversions were 68.9, 49.4, and 28.92, respectively. To the best of our knowledge, WSUCF1 crude xylanase cocktail is among the most thermostable xylanases produced by thermophilic Geobacillus spp. and other thermophilic microbes (optimum growth temperature ≤70ºC. High thermostability, activity over wide range of temperatures, and better xylan hydrolysis than commercial enzymes make WSUCF1 crude xylanase suitable for thermophilic lignocellulose bioconversion processes.

  6. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans.

    Science.gov (United States)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-10-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity after 49h incubated at 50°C. XlnB had its highest activity against wheat arabinoxylan while XlnC had the best activity against beechwood xylan. Both enzymes were completely inhibited by SDS and HgCl2. Xylotriose at 1mg/ml also totally inibited XlnB activity. TLC analysis showed that the main product of beechwood xylan hydrolysis by XlnB and XlnC was xylotetraose. An additive effect was shown between XlnB and XlnC and the xylanases of two tested commercial cocktails. Sugarcane bagasse saccharification results showed that these two commercial enzymatic cocktails were able to release more glucose and xylose after supplementation with XlnB and XlnC.

  7. Heterologous expression of xylanase enzymes in lipogenic yeast Yarrowia lipolytica.

    Directory of Open Access Journals (Sweden)

    Wei Wang

    Full Text Available To develop a direct microbial sugar conversion platform for the production of lipids, drop-in fuels and chemicals from cellulosic biomass substrate, we chose Yarrowia lipolytica as a viable demonstration strain. Y. lipolytica is known to accumulate lipids intracellularly and is capable of metabolizing sugars to produce lipids; however, it lacks the lignocellulose-degrading enzymes needed to break down biomass directly. While research is continuing on the development of a Y. lipolytica strain able to degrade cellulose, in this study, we present successful expression of several xylanases in Y. lipolytica. The XynII and XlnD expressing Yarrowia strains exhibited an ability to grow on xylan mineral plates. This was shown by Congo Red staining of halo zones on xylan mineral plates. Enzymatic activity tests further demonstrated active expression of XynII and XlnD in Y. lipolytica. Furthermore, synergistic action in converting xylan to xylose was observed when XlnD acted in concert with XynII. The successful expression of these xylanases in Yarrowia further advances us toward our goal to develop a direct microbial conversion process using this organism.

  8. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans.

    Science.gov (United States)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-10-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity after 49h incubated at 50°C. XlnB had its highest activity against wheat arabinoxylan while XlnC had the best activity against beechwood xylan. Both enzymes were completely inhibited by SDS and HgCl2. Xylotriose at 1mg/ml also totally inibited XlnB activity. TLC analysis showed that the main product of beechwood xylan hydrolysis by XlnB and XlnC was xylotetraose. An additive effect was shown between XlnB and XlnC and the xylanases of two tested commercial cocktails. Sugarcane bagasse saccharification results showed that these two commercial enzymatic cocktails were able to release more glucose and xylose after supplementation with XlnB and XlnC. PMID:27235731

  9. Biobleaching application of cellulase poor and alkali stable xylanase from Bacillus pumilus SV-85S

    OpenAIRE

    Nagar, Sushil; Jain, R. K.; Thakur, Vasanta Vadde; Gupta, Vijay Kumar

    2012-01-01

    The potential of extracellular alkali stable and thermo tolerant xylanase produced by Bacillus pumilus SV-85S through solid state fermentation was investigated in pulp bleaching in association with conventional bleaching using chlorine and chlorine dioxide. The biobleaching of kraft pulp with xylanase was the most effective at an enzyme dose of 10 IU/g oven dried pulp, pH 9.0 and 120 min incubation at 55 °C. Under the optimized conditions, xylanase pretreatment reduced Kappa number by 1.6 poi...

  10. Purification and preliminary characterization of a xylanase from Thermomyces lanuginosus strain SS-8

    OpenAIRE

    Shrivastava, Smriti; Shukla, Pratyoosh; Mukhopadhyay, Kunal

    2011-01-01

    Thermomyces lanuginosus SS-8 was isolated from soil samples that had been collected from near self-heating plant material and its extracellular cellulase-free xylanase purified approximately 160-fold using ion exchange chromatography and continuous elution electrophoresis. This xylanase was thermoactive (optimum temperature 60 °C) at pH 6.0 and had a molecular weight of 23.79 kDa as indicated by SDS-PAGE electrophoresis. The xylanase rapidly hydrolyzed xylan directly to xylose without the pro...

  11. A Highly Thermostable Xylanase from Stenotrophomonas maltophilia: Purification and Partial Characterization

    OpenAIRE

    Abhay Raj; Sharad Kumar; Sudheer Kumar Singh

    2013-01-01

    Seven xylanolytic bacterial strains were isolated from saw-dust dump soil. The bacterial strain X6 was selected on the basis of the highest xylanase activity with no cellulase contamination. It was identified as Stenotrophomonas maltophilia by biochemical tests and 16S rRNA gene sequencing approach. Xylanase production studies by S. maltophilia on different commercial xylans and agro-industrial residues suggested that wheat bran was the best carbon source for xylanase production (26.4 ± 0.6 I...

  12. Purification and properties of xylanase A from alkali-tolerant Bacillus sp. strain BP-23.

    OpenAIRE

    A. Blanco; Vidal, T; Colom, J F; Pastor, F I

    1995-01-01

    Xylanase A from the recently isolated Bacillus sp. strain BP-23 was purified to homogeneity. The enzyme shows a molecular mass of 32 kDa and an isoelectric point of 9.3. Optimum temperature and pH for xylanase activity were 50 degrees C and 5.5 respectively. Xylanase A was completely inhibited by N-bromosuccinimide. The main products of birchwood xylan hydrolysis were xylotetraose and xylobiose. The enzyme was shown to facilitate chemical bleaching of pulp, generating savings of 38% in terms ...

  13. High genetic diversity and different distributions of glycosyl hydrolase family 10 and 11 xylanases in the goat rumen.

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    Guozeng Wang

    Full Text Available BACKGROUND: The rumen harbors a complex microbial ecosystem for efficient hydrolysis of plant polysaccharides which are the main constituent of the diet. Xylanase is crucial for hemicellulose hydrolysis and plays an important role in the plant cell wall degradation. Xylanases of ruminal strains were widely studied, but few studies have focused on their diversity in rumen microenvironment. METHODOLOGY/PRINCIPAL FINDINGS: We explored the genetic diversity of xylanases belonging to two major glycosyl hydrolase families (GH 10 and 11 in goat rumen contents by analyzing the amplicons generated with two degenerate primer sets. Fifty-two distinct GH 10 and 35 GH 11 xylanase gene fragments (similarity <95% were retrieved, and most had low identities with known sequences. Based on phylogenetic analysis, all GH 10 xylanase sequences fell into seven clusters, and 88.5% of them were related to xylanases from Bacteroidetes. Five clusters of GH 11 xylanase sequences were identified. Of these, 85.7% were related to xylanases from Firmicutes, and 14.3% were related to those of rumen fungi. Two full-length xylanase genes (one for each family were directly cloned and expressed in Escherichia coli. Both the recombinant enzymes showed substantial xylanase activity, and were purified and characterized. Combined with the results of sheep rumen, Bacteroidetes and Firmicutes are the two major phyla of xylan-degrading microorganisms in rumen, which is distinct from the representatives of other environments such as soil and termite hindgut, suggesting that xylan-degrading microorganisms are environment specific. CONCLUSION/SIGNIFICANCE: The numerous new xylanase genes suggested the functional diversity of xylanase in the rumen microenvironment which may have great potential applications in industry and agriculture. The phylogenetic diversity and different distributions of xylanase genes will help us understand their roles in plant cell wall degradation in the rumen

  14. Mutation-Screening in Xylanase-Producing Strains by Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    李市场; 吴敏; 姚建铭; 潘仁瑞; 余增亮

    2005-01-01

    With ion implantation (N+, energy 10 keV and dosage 1.56×1015N+ cm-2), a high xylanase-producing strain Aspergillus niger N212 was selected. Based on an orthogonal experiment, an optimal fermentation condition was designed for this high-yield strain. The suitable medium was composed of 8% corncob; 1.0% wheat bran; 0.1% TWEEN20; 0.5% (NH4)2SO4;3.0×10-4. At present, under our experiment condition, xylanase activity of Aspergillus niger N212 reached a level of 600 IU/ml, almost increased by 100% in xylanase production and the time of yielding xylanase was largely reduced to 12 h at 28 ℃.

  15. Extracellular xylanase production by Pleurotus species on lignocellulosic wastes under in vivo condition using novel pretreatment.

    Science.gov (United States)

    Singh, M P; Pandey, A K; Vishwakarma, S K; Srivastava, A K; Pandey, V K

    2012-01-01

    The production of extracellular xylanase by three species of Pleurotus species i.e. P. florida, P. flabellatus and P. sajor caju was studied under in vivo condition during their cultivation on pretreated lignocellulosic wastes. Neem (Azadirachta indica) oil and ashoka (Saraca indica) leaves extract were used for pretreatment of paddy straw and wheat straw. Between these two wastes, paddy straw pretreated with neem oil, supported better xylanase production than wheat straw. Initially, xylanase production was low but it increased in subsequent days and reached at peak on 25th day of cultivation of Pleurotus species. Thereafter, there was decrease in the activity of the enzyme. On 25th day of incubation P. florida produced maximum xylanase on neem oil pretreated paddy straw i.e. 10.59 Uh—1ml—1. Among the three species, P. florida showed maximum enzyme activity followed by P. flabellatus and P. sajor caju. PMID:23273208

  16. Purification and characterization of a moderately thermostable xylanase from Bacillus sp. strain SPS-0.

    Science.gov (United States)

    Bataillon; Nunes Cardinali A; Castillon; Duchiron

    2000-02-01

    A Bacillus spp. strain SPS-0, isolated from a hot spring in Portugal, produced an extracellular xylanase upon growth on wheat bran arabinoxylan. The enzyme was purified to homogeneity by ammonium sulfate precipitation, anion exchange, gel filtration, and affinity chromatography. The optimum temperature and pH for activity was 75 degrees C and 6.0. Xylanase was stable up to 70 degrees C for 4 h at pH 6.0 in the presence of xylane. Xylanase was completely inhibited by the Hg(2+) ions. beta-Mercaptoethanol, dithiothreitol, and Mn(2+) stimulated the xylanase activity. The products of birchwood xylan hydrolysis were xylose, xylobiose, xylotriose, and xylotetraose. Kinetic experiments at 60 degrees C and pH 6.0 gave V(max) and K(m)values of 2420 nkat/mg and 0.7 mg/ml.

  17. [Cellulase and xylanase activities of Fusarium Lk:Fr. genus fungi of different trophic groups].

    Science.gov (United States)

    Kurchenko, I M; Sokolova, O V; Zhdanova, N M; Iarynchyn, A M; Iovenko, O M

    2008-01-01

    A comparative analysis of cellulase and xylanase activities of 26 fungal strains of phytopathogenic, saprophytic and endophytic Fusarium species has been realized using the qualitative reactions. The rare of their linear growth on the media with carboxymethyl cellulose or xylane has been studied. It was shown that the fungi of genus Fusarium belonging to different trophic groups possessed low activities of investigated enzymes as a whole, but in endophytic strains their levels were lower than in phytopathogenic ones. At the same time the distinct strain dependence of cellulase and xylanase activities was fixed in the fungi of different trophic groups. As far as the cellulase and xylanase activities in phytopathogenic isolates varied from complete absence to high levels, and since the activity maximum for each of the investigated strains was observed in different growth terms the conclusion was made that the cellulase and xylanase activities could not be considered as possible markers of the fungal isolate pathogenicity on the strain level.

  18. Influence of agitation speeds and aeration rates on the Xylanase activity of Aspergillus niger SS7

    Directory of Open Access Journals (Sweden)

    Yasser Bakri

    2011-08-01

    Full Text Available In this study, the effect of agitation and aeration rates on xylanase activity of Aspergillus niger SS7 in 3-litre stirred tank bioreactor was investigated. The agitation rates tested were 100, 200 and 300 rpm at each airflow rates of 0.5, 1.0 and 1.5 vvm. The maximum xylanase activity in mono- agitator system was at the agitation speed of 200 rpm and aeration rate of 1.0 vvm. In bi-agitator system, at low agitation speed (100 rpm, the xylanase activity was enhanced by 13% compared to mono- agitator system for an aeration rate of 1.0 vvm. Xylanase productivity in continuous culture was higher by approximately 3.5 times than in batch culture.

  19. Integrating a xylanase treatment into an industrial-type sequence for eucalyptus kraft pulp bleaching

    OpenAIRE

    Fillat Latorre, Úrsula; Roncero Vivero, María Blanca; Sacón, Vera Maria; Bassa, Alexandre

    2012-01-01

    The influence of a treatment with two commercial xylanases on pulp and effluents obtained after the bleaching stages in the OXAZDP (O, oxygen stage; X, xylanase treatment; A, acid stage; Z, ozone stage; D, chlorine dioxide stage; P, hydrogen peroxide stage) sequence was studied. Also, the potential saving in chlorine dioxide was assessed. The enzyme treatment was performed on pulp containing some black liquor since the operating conditions were close to the conditions used in the storage towe...

  20. Production, purification and characterization of xylanase using alkalo-thermophilic Bacillus halodurans KR-1

    OpenAIRE

    Krityanand Kumar Mahatman; Neha Garg; Ranjeeta Chauhan; Anil Kumar

    2010-01-01

    Xylanase (EC. 3.2.1.8) has been isolated from an alkalo-thermophilic bacteria, Bacillus halodurans strain KR-1 isolated from the soil near river bed at Indore. The bacteria secreted xylanase in the growth medium in the presence of xylan. The production of the enzyme was induced in the presence of glucose, mannose, lactose and maltose whereas presence of starch, cellulose and sucrose retarded in enzyme production. The presence of casein, peptone, sodium nitrate and potassium nitrate as nitroge...

  1. Crystal Structure of Talaromyces cellulolyticus (Formerly Known as Acremonium cellulolyticus) GH Family 11 Xylanase

    OpenAIRE

    Kataoka, Misumi; Akita, Fusamichi; Maeno, Yuka; Inoue, Benchaporn; Inoue, Hiroyuki; Ishikawa, Kazuhiko

    2014-01-01

    Talaromyces cellulolyticus (formerly known as Acremonium cellulolyticus) is one of the mesophilic fungi that can produce high levels of cellulose-related enzymes and are expected to be used for the degradation of polysaccharide biomass. In silico analysis of the genome sequence of T. cellulolyticus detected seven open reading frames (ORFs) showing homology to xylanases from glycoside hydrolase (GH) family 11. The gene encoding the GH11 xylanase C (TcXylC) with the highest activity was used fo...

  2. Purification and Characterization of Aeromonas caviae ME-1 Xylanase V, Which Produces Exclusively Xylobiose from Xylan

    OpenAIRE

    Kubata, Bruno Kilunga; Suzuki, Tohru; Horitsu, Hiroyuki; Kawai, Keiichi; Takamizawa, Kazuhiro

    1994-01-01

    A xylanase, which produces exclusively xylobiose from oat spelt and birch xylans, was isolated from the culture medium of Aeromonas caviae ME-1. The enzyme (xylanase V) was purified by ammonium sulfate fractionation, hydrophobic interaction, and ion-exchange and gel filtration chromatographies. The homogeneity of the final preparation was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and agarose gel electrofocusing. The molecular mass and isoelectric point of the x...

  3. A Highly Thermostable Xylanase from Stenotrophomonas maltophilia: Purification and Partial Characterization

    Directory of Open Access Journals (Sweden)

    Abhay Raj

    2013-01-01

    Full Text Available Seven xylanolytic bacterial strains were isolated from saw-dust dump soil. The bacterial strain X6 was selected on the basis of the highest xylanase activity with no cellulase contamination. It was identified as Stenotrophomonas maltophilia by biochemical tests and 16S rRNA gene sequencing approach. Xylanase production studies by S. maltophilia on different commercial xylans and agro-industrial residues suggested that wheat bran was the best carbon source for xylanase production (26.4 ± 0.6 IU/mL. The studies with inorganic and organic nitrogen sources suggested yeast extract as the best support for xylanase production (25 ± 0.6 IU/mL. Maximum xylanase production was observed at initial medium pH = 8.0 (23.8 ± 0.4 IU/mL with production at pH = 7.0 and pH = 9.0 being almost comparable. Xylanase produced by S. maltophilia was purified to homogeneity using ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. The final purification was 5.43-fold with recovery of 19.18%. The molecular weight of the purified xylanase protein was ~142 kDa. Both crude and purified xylanase had good stability at pH = 9.0 and 80°C with activity retention greater than 90% after 30 min incubation. The enzyme stability at high temperature and alkaline pH make it potentially effective for industrial applications.

  4. Mutagenesis and Screening of High Yield Xylanase Production Strain of Aspergillus usamii by Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    李永泉; 陈时飞; 岑沛霖

    2003-01-01

    A high yield xylanase producing strain, A. usamii L336-23, was screened out from its parent strain A.usamii L336 after microwave irradiation. Its productivity of xylanase activity increased by 35.7% from 21000μ·m1-1 to 28500μ·m1-1 and was stable after frequent subcultures and storage for more than two months.The mechanism of microwave mutation was also discussed.

  5. Metabolizable energy values of diets supplemented with xylanase determined with laying hens

    Directory of Open Access Journals (Sweden)

    Karina Márcia Ribeiro de Souza

    2012-12-01

    Full Text Available The objective of this study was to evaluate the effect of the supplementation of xylanase in diets with reduced energy level on the apparent metabolizable energy corrected for nitrogen, determined with laying hens at 14, 36, 60 and 80 weeks of age. Four digestibility trials were conducted, using 80 Hy-line W36 laying hens aged 14, 36, 60 and 80 weeks of age. Birds were distributed in a completely randomized design in 2 × 2 factorial arrangement (energy level × inclusion of xylanase, totaling four treatments with 10 replicates of two birds each. Treatments were: positive control (balanced diet for their age; positive control + xylanase; negative control (diet with reduction of 100 kcal/kg in the level of metabolizable energy; and negative control + xylanase. Xylanase, produced by microorganism Trichoderma reesei, was added to the diets at 100 g/t (16,000 BXU/kg for diets fed at 14 weeks and 75 g/t for diets of 36, 60 and 80 weeks (12,000 BXU/kg. The data obtained were subjected to analysis of variance at 5% probability. Supplementation of xylanase promoted higher values for AME (apparent metabolizable energy and AMEn (apparent metabolizable energy corrected for nitrogen determined with 80-week-old laying hens, subjected to diet with energy level according to the nutritional requirements for their age. Supplementation of xylanase increases the matabolizability coefficient of the dietary crude protein and improves the nitrogen retention of laying hens at 14 weeks. In addition, xylanase associated with adequate levels of dietary energy promotes higher values for AME and AMEn determined with laying hens at 80 weeks of age.

  6. Removal of hexenuronic acid by xylanase to reduce adsorbable organic halides formation in chlorine dioxide bleaching of bagasse pulp.

    Science.gov (United States)

    Nie, Shuangxi; Wang, Shuangfei; Qin, Chengrong; Yao, Shuangquan; Ebonka, Johnbull Friday; Song, Xueping; Li, Kecheng

    2015-11-01

    Xylanase-aided chlorine dioxide bleaching of bagasse pulp was investigated. The pulp was pretreated with xylanase and followed a chlorine dioxide bleaching stage. The ATR-FTIR and XPS were employed to determine the surface chemistry of the control pulp, xylanase treated and chlorine dioxide treated pulps. The hexenuronic acid (HexA) could obviously be reduced after xylanase pretreatment, and the adsorbable organic halides (AOX) were reduced after chlorine dioxide bleaching. Compared to the control pulp, AOX could be reduced by 21.4-26.6% with xylanase treatment. Chlorine dioxide demand could be reduced by 12.5-22% to achieve the same brightness. The ATR-FTIR and XPS results showed that lignin and hemicellulose (mainly HexA) were the main source for AOX formation. Xylanase pretreatment could remove HexA and expose more lignin, which decreased the chlorine dioxide demand and thus reduced formation of AOX. PMID:26263004

  7. Pretreatment with xylanase and its significance in hemicellulose removal from mixed hardwood kraft pulp as a process step for viscose.

    Science.gov (United States)

    Kaur, Prabhjot; Bhardwaj, Nishi K; Sharma, Jitender

    2016-07-10

    The upturn of viscose fiber market has triggered an augmented dissolving pulp usage over the last decade. Dissolving pulp is feasible to obtain from kraft pulp after two essential steps including hemicellulose removal and subsequent pulp activation. Prerequisite of conversion being hemicellulose reduction can be gently done by using xylanase treatment prior to alkali extraction. Herein, the significance of xylanase treatment and the optimum xylanase dose required in conjunction with subsequent alkali extraction was investigated. An increase in xylanase dose prior to alkali extraction had no significant effect on pentosans while the Fock reactivity and viscosity both improved at the dose of 50AXU/g. Also, alkali extraction without xylanase pretreatment resulted in decreased Fock reactivity, alpha cellulose, brightness and viscosity of paper grade pulp. A moderate dose of xylanase prior to alkali extraction can thus be used to facilitate the hemicellulose removal while simultaneously protecting the native structure of cellulose. PMID:27106156

  8. Thermostable microbial xylanases for pulp and paper industries: trends, applications and further perspectives.

    Science.gov (United States)

    Kumar, Vishal; Marín-Navarro, Julia; Shukla, Pratyoosh

    2016-02-01

    Xylanases are enzymes with biotechnological relevance in a number of fields, including food, feed, biofuel, and textile industries. Their most significant application is in the paper and pulp industry, where they are used as a biobleaching agent, showing clear economic and environmental advantages over chemical alternatives. Since this process requires high temperatures and alkali media, the identification of thermostable and alkali stable xylanases represents a major biotechnological goal in this field. Moreover, thermostability is a desirable property for many other applications of xylanases. The review makes an overview of xylanase producing microorganisms and their current implementation in paper biobleaching. Future perspectives are analyzed focusing in the efforts carried out to generate thermostable enzymes by means of modern biotechnological tools, including metagenomic analysis, enzyme molecular engineering and nanotechnology. Furthermore, structural and mutagenesis studies have revealed critical sites for stability of xylanases from glycoside hydrolase families GH10 and GH11, which constitute the main classes of these enzymes. The overall conclusions of these works are summarized here and provide relevant information about putative weak spots within xylanase structures to be targeted in future protein engineering approaches. PMID:26754672

  9. Thermostable microbial xylanases for pulp and paper industries: trends, applications and further perspectives.

    Science.gov (United States)

    Kumar, Vishal; Marín-Navarro, Julia; Shukla, Pratyoosh

    2016-02-01

    Xylanases are enzymes with biotechnological relevance in a number of fields, including food, feed, biofuel, and textile industries. Their most significant application is in the paper and pulp industry, where they are used as a biobleaching agent, showing clear economic and environmental advantages over chemical alternatives. Since this process requires high temperatures and alkali media, the identification of thermostable and alkali stable xylanases represents a major biotechnological goal in this field. Moreover, thermostability is a desirable property for many other applications of xylanases. The review makes an overview of xylanase producing microorganisms and their current implementation in paper biobleaching. Future perspectives are analyzed focusing in the efforts carried out to generate thermostable enzymes by means of modern biotechnological tools, including metagenomic analysis, enzyme molecular engineering and nanotechnology. Furthermore, structural and mutagenesis studies have revealed critical sites for stability of xylanases from glycoside hydrolase families GH10 and GH11, which constitute the main classes of these enzymes. The overall conclusions of these works are summarized here and provide relevant information about putative weak spots within xylanase structures to be targeted in future protein engineering approaches.

  10. Xylanase production by a local fungal isolate, Aspergillus niger USM AI 1 via solid state

    Directory of Open Access Journals (Sweden)

    Ibrahim Che Omar

    2005-03-01

    Full Text Available Isolate USM A1 I which was identified to be Aspergillus niger was selected as a potential producer of xylanase via a solid state fermentation system (SSF using palm kernel cake (PKC as substrate. The modification of the physical conditions of the SSF system indicated that the xylanase activity was 23.97 U/g PKC at the moisture ratio of 1:0.75 of PKC: moistening agent with the inoculum size of 1¥104 spores/ml and cultivated at the ambient temperature (28±3ºC. The supplementation of additional carbon and nitrogen sources in the PKC medium could enhance enzyme productivity. The maximum production of xylanase and growth obtained with the supplementation of xylose at 0.75% (w/w were 25.40 U/g and 1.69 mg glucosamine/ g PKC. Moreover, the presence of NaNO3 at 0.075% (w/w as additional nitrogen source further enhanced xylanase production to 33.99 U/g PKC although the growth remained unchanged at about 1.67 mg glucosa- mine/g PKC. The optimized conditions showed an increased xylanase production by 157% compared to before the optimization of the SSF system. The xylanase productivity was 23.12 U/mg glucosamine after optimization and 11.72 U/mg glucosamine before optimization.

  11. Xylanase production with xylan rich lignocellulosic wastes by a local soil isolate of Trichoderma viride.

    Science.gov (United States)

    Goyal, Meenakshi; Kalra, K L; Sareen, V K; Soni, G

    2008-07-01

    In the present study, cultural and nutritional conditions for enhanced production of xylanase by a local soil isolate of Trichoderma viride, using various lignocellulosic substrates in submerged culture fermentation have been optimized. Of the lignocellulosics used, maize straw was the best inducer followed by jowar straw for xylanase production. The highest activity achieved was between 14 to 17 days of fermentation. A continuous increase in xylanase production was observed with increasing level of lignocellulosics in the medium and highest activity was observed with maize straw at 5% level. Xylanase production with higher levels of lignocellulosics (3 to 5%) of maize, jowar and barseem was found to be higher as compared to that with commercial xylan as carbon source. Sodium nitrate was the best nitrogen source among the six sources used. Maximum xylanase production was achieved with initial medium pH of 3.5-4.0 and incubation temperature of 25ºC.The enzyme preparation was effective in bringing about saccharification of different lignocellulosics. The xylanase production could be further improved by using alkali treated straw as carbon source. PMID:24031262

  12. Synergistic effect of cellulase and xylanase during hydrolysis of natural lignocellulosic substrates.

    Science.gov (United States)

    Song, Hui-Ting; Gao, Yuan; Yang, Yi-Min; Xiao, Wen-Jing; Liu, Shi-Hui; Xia, Wu-Cheng; Liu, Zi-Lu; Yi, Li; Jiang, Zheng-Bing

    2016-11-01

    Synergistic combination of cellulase and xylanase has been performed on pre-treated substrates in many previous studies, while few on natural substrates. In this study, three unpretreated lignocellulosic substrates were studied, including corncob, corn stover, and rice straw. The results indicated that when the mixed cellulase and xylanase were applied, reducing sugar concentrations were calculated as 19.53, 15.56, and 17.35mg/ml, respectively, based on the 3,5 dinitrosalicylic acid (DNS) method. Compared to the treatment with only cellulose, the hydrolysis yields caused by mixed cellulase and xylanase were improved by 133%, 164%, and 545%, respectively. In addition, the conversion yield of corncob, corn stover, and rice straw by cellulase-xylanase co-treatment reached 43.9%, 48.5%, and 40.2%, respectively, based on HPLC analysis, which confirmed the synergistic effect of cellulase-xylanase that was much higher than either of the single enzyme treatment. The substrate morphology was also evaluated to explore the synergistic mechanism of cellulase-xylanase. PMID:27560367

  13. A new acidophilic endo-β-1,4-xylanase from Penicillium oxalicum: cloning, purification, and insights into the influence of metal ions on xylanase activity.

    Science.gov (United States)

    Liao, Hanpeng; Sun, Shaowei; Wang, Pan; Bi, Wenli; Tan, Shiyong; Wei, Zhong; Mei, Xinlan; Liu, Dongyang; Raza, Waseem; Shen, Qirong; Xu, Yangchun

    2014-07-01

    A new acidophilic xylanase (XYN11A) from Penicillium oxalicum GZ-2 has been purified, identified and characterized. Synchronized fluorescence spectroscopy was used for the first time to evaluate the influence of metal ions on xylanase activity. The purified enzyme was identified by MALDI TOF/TOF mass spectrometry, and its gene (xyn11A) was identified as an open reading frame of 706 bp with a 68 bp intron. This gene encodes a mature protein of 196 residues with a predicted molecular weight of 21.3 kDa that has the 100 % identity with the putative xylanase from the P. oxalicum 114-2. The enzyme shows a structure comprising a catalytic module family 10 (GH10) and no carbohydrate-binding module family. The specific activities were 150.2, 60.2, and 72.6 U/mg for beechwood xylan, birchwood xylan, and oat spelt xylan, respectively. XYN11A exhibited optimal activity at pH 4.0 and remarkable pH stability under extremely acidic condition (pH 3). The specific activity, K m and V max values were 150.2 U/mg, 30.7 mg/mL, and 403.9 μmol/min/mg for beechwood xylan, respectively. XYN11A is a endo-β-1,4-xylanase since it release xylobiose and xylotriose as the main products by hydrolyzing xylans. The activity of XYN11A was enhanced 155 % by 1 mM Fe(2+) ions, but was inhibited strongly by Fe(3+). The reason of enhancing the xylanase activity of XYN11A with 1 mM Fe(2+) treatment may be responsible for the change of microenvironment of tryptophan residues studied by synchronous fluorescence spectrophotometry. Inhibition of the xylanase activity by Fe(3+) was first time demonstrated to associate tryptophan fluorescence quenching. PMID:24818699

  14. Kinetics of Xylanase Fermentation by Recombinant Escherichia coli DH5α in Shake Flask Culture

    OpenAIRE

    Farliahati Mohd Rusli; Mohd Shamzi Mohamed; Rosfarizan Mohamad; Ni N. Tri Puspaningsih; Arbakariya A. Ariff

    2009-01-01

    Problem statement: Interest in xylanase enzyme application has markedly increased in pulp and paper processing industries. The switch to xylanase-producing recombinant Escherichia coli DH5α pTP510 is seen here as an economic alternative towards higher productivity and easier downstream purification. Modeling of E. coli DH5α growth and enzyme secretion is thus desired for future optimization in fermentation process. Approach: Kinetics of intracellular xylanase fermentation by a recom...

  15. Functional characterization of Penicillium occitanis Pol6 and Penicillium funiculosum GH11 xylanases.

    Science.gov (United States)

    Driss, Dorra; Berrin, Jean Guy; Juge, Nathalie; Bhiri, Fatma; Ghorbel, Raoudha; Chaabouni, Semia Ellouz

    2013-08-01

    Xylanases are hemicellulolytic enzymes, which are responsible for the degradation of heteroxylans constituting the lignocellulosic plant cell wall. Xylanases from the GH11 family are considered as true xylanases because of their high substrate specificity. In order to study in depth a crucial difference in the thumb region between two closely related xylanases from Penicillium in terms of kinetic parameters and inhibition sensitivity, the GH11 xylanases from Penicillium occitanis Pol6 (PoXyn3) and from Penicillium funiculosum (PfXynC) were heterologously expressed in Pichia pastoris. The PoXyn3 and PfXynC cDNAs encoding mature xylanases were cloned into pGAPZαA vectors and integrated into the genome of P. pastoris X-33 under the control of the glyceraldehyde 3-phosphate dehydrogenase constitutive promoter. PfXynC was expressed as a His-tagged recombinant protein and purified from the supernatant homogeneity by a one-step purification protocol using immobilized metal affinity chromatography. The recombinant PoXyn3 was purified using a single anion-exchange chromatography. The purified recombinant enzymes were optimally active at 45°C and pH 4.0 for PoXyn3 and 40°C and pH 3.0 for PfXynC. The measured kinetic parameters (k(cat) and Vmax) showed that PfXynC was five times more active than PoXyn3 irrespective of the substrate whereas the apparent affinity (K(m)) was similar. The recombinant enzymes showed distinct sensitivity to the Triticum aestivum xylanase inhibitor TAXI-I.

  16. Efficiency of different xylanase preparations in diets for pekin ducks.

    Science.gov (United States)

    Timmler, R; Rodehutscord, M

    2001-01-01

    Four experiments were conducted with a total of 2288 pekin ducks. Day-old ducklings were group-penned on straw bedding and were fed complete, pelleted diets ad libitum for up to 49 days depending on experiment. In each experiment, starter diets (until day 21) and grower diets (from day 22) were used adequate in ME content and nutrient content. The sum of wheat, rye, and triticale amounted to at least 57% (starter diet) and 63% (grower diet), respectively. The inclusion level of wheat, rye, and triticale was different between experiments, with a maximum rye inclusion of 45%. Five different enzyme preparations all having, 1,4-beta-xylanase as the main activity were considered in this study with either one (2 preparations) or three (3 preparations) levels of supplementation. The effect of enzyme supplementation on ileal digesta viscosity was studied at the end of two experiments comprising 4 enzyme preparations. A significant reduction in digesta viscosity was determined for all preparations. The viscosity of digesta was higher in birds that were fed 45% rye in their diet as compared to those fed a diet based on triticale and wheat, even with enzyme supplementation. Differences in digesta viscosity were not reflected in growth or feed conversion data. In one experiment, the body weight of ducks on day 21 was significantly improved by enzyme supplementation. This effect disappeared with progress in experiment. In another experiment, feed intake was significantly improved with enzyme supplementation. Apart from this, no statistically significant improvement in performance could be detected. On overall average, the final BW of ducks fed an enzyme was (as compared to the unsupplemented control = 100), 100, and the feed conversion ratio was 101. There is no indication from the growth and feed conversion data that an enzyme effect becomes more pronounced with increasing inclusion rate of soluble NSP by rye. It is concluded that supplementary xylanases are efficient in

  17. EFFECT OF XYLANASE TREATMENT ON DEWATERING PROPERTIES OF BIRCH KRAFT PULP

    Directory of Open Access Journals (Sweden)

    Minna Marianne Blomstedt

    2010-04-01

    Full Text Available In this study it was shown that the enzymatic removal of xylan from ECF-bleached birch kraft pulp enhances the water removal from the pulp, especially in the late stages of pulp drying. The effect of xylanase treatments on dewatering was clarified by using a moving belt former (MBF, a press simulator (MTS, and an IR-drying equipment, to simulate and to measure dewatering properties on wire, press and drying sections of a paper machine. The xylanase treatment slightly increased the pulp freeness indicating improved pulp drainage properties. At the moving belt former, however, no significant changes that would indicate enhanced dewatering in forming were observed. The xylanase treatments slightly enhanced the dewatering in wet pressing and furthermore, at the thermal drying the xylanase treatment had a positive effect on the dry solid content (DSC development, and time to reach the 95% dry solids content was reduced by up to 15%. This was also confirmed by the decrease in the fiber saturation point (FSP values and the amount of bulk water. Our results indicate that the xylanase treatment affected the water-binding xylan in the fiber cell wall, yielding enhanced dewatering properties, without deteriorating the pulp and paper properties.

  18. Structure-Specificity Relationships of an Intracellular Xylanase from Geobacillus stearothermophilus

    Energy Technology Data Exchange (ETDEWEB)

    Solomon,V.; Teplitsky, A.; Shulami, S.; Zolotnitsky, G.; Shoham, Y.; Shoham, G.

    2007-01-01

    Geobacillus stearothermophilus T-6 is a thermophilic Gram-positive bacterium that produces two selective family 10 xylanases which both take part in the complete degradation and utilization of the xylan polymer. The two xylanases exhibit significantly different substrate specificities. While the extracellular xylanase (XT6; MW 43.8 kDa) hydrolyzes the long and branched native xylan polymer, the intracellular xylanase (IXT6; MW 38.6 kDa) preferentially hydrolyzes only short xylo-oligosaccharides. In this study, the detailed three-dimensional structure of IXT6 is reported, as determined by X-ray crystallography. It was initially solved by molecular replacement and then refined at 1.45 {angstrom} resolution to a final R factor of 15.0% and an R{sub free} of 19.0%. As expected, the structure forms the classical ({alpha}/{beta}){sub 8} fold, in which the two catalytic residues (Glu134 and Glu241) are located on the inner surface of the central cavity. The structure of IXT6 was compared with the highly homologous extracellular xylanase XT6, revealing a number of structural differences between the active sites of the two enzymes. In particular, structural differences derived from the unique subdomain in the carboxy-terminal region of XT6, which is completely absent in IXT6. These structural modifications may account for the significant differences in the substrate specificities of these otherwise very similar enzymes.

  19. Enhancing xylanase production in the thermophilic fungus Myceliophthora thermophila by homologous overexpression of Mtxyr1.

    Science.gov (United States)

    Wang, Juan; Wu, Yaning; Gong, Yanfen; Yu, Shaowen; Liu, Gang

    2015-09-01

    The xylanase regulator 1 protein in Myceliophthora thermophila ATCC42464 (MtXyr1) is 60 % homologous with that of Trichoderma reesei. However, MtXyr1's regulatory role on cellulolytic and xylanolytic genes in M. thermophila is unknown. Herein, MtXyr1 was overexpressed under the control of the MtPpdc (pyruvate decarboxylase) promoter. Compared with the wild type, the extracellular xylanase activities of the transformant cultured in non-inducing and inducing media for 120 h were 25.19- and 9.04-fold higher, respectively. The Mtxyr1 mRNA level was 300-fold higher than in the wild type in corncob-containing medium. However, the filter paper activity and endoglucanase activities were unchanged in corncob-containing medium and glucose-containing medium. The different zymograms between the transformant and the wild type were analyzed and identified by mass spectrometry as three xylanases of the glycoside hydrolase (GH) family 11. Thus, overexpression of xyr1 resulted in enhanced xylanase activity in M. thermophila. Xylanase production could be improved by overexpressing Mtxyr1 in M. thermophila. PMID:26173497

  20. Isolation, Production, and Characterization of Thermotolerant Xylanase from Solvent Tolerant Bacillus vallismortis RSPP-15

    Directory of Open Access Journals (Sweden)

    Rajeeva Gaur

    2015-01-01

    Full Text Available Sixty bacterial strains isolated from the soils sample in the presence of organic solvent were screened for xylanase production. Among them, strain RSPP-15 showed the highest xylanase activity which was identified as Bacillus vallismortis. The isolate showed maximum xylanase production (3768 U/mL in the presence of birch wood xylan and beef extract at 55°C pH 7.0 within 48 h of incubation. The enzyme activity and stability were increased 181.5, 153.7, 147.2, 133.6, and 127.9% and 138.2, 119.3, 113.9, 109, and 104.5% in the presence of Co2+, Ca2+, Mg+2, Zn+2, and Fe+3 ions (10 mM. Xylanase activity and stability were strongly inhibited in the presence of Hg and Cu ions. The enzyme was also stable in the presence of 30% of n-dodecane, isooctane, n-decane, xylene, toluene, n-hexane, n-butanol, and cyclohexane, respectively. The presence of benzene, methanol, and ethanol marginally reduced the xylanase stability, respectively. This isolate may be useful in several industrial applications owing to its thermotolerant and organic solvent resistance characteristics.

  1. Crystal structure of Talaromyces cellulolyticus (formerly known as Acremonium cellulolyticus) GH family 11 xylanase.

    Science.gov (United States)

    Kataoka, Misumi; Akita, Fusamichi; Maeno, Yuka; Inoue, Benchaporn; Inoue, Hiroyuki; Ishikawa, Kazuhiko

    2014-10-01

    Talaromyces cellulolyticus (formerly known as Acremonium cellulolyticus) is one of the mesophilic fungi that can produce high levels of cellulose-related enzymes and are expected to be used for the degradation of polysaccharide biomass. In silico analysis of the genome sequence of T. cellulolyticus detected seven open reading frames (ORFs) showing homology to xylanases from glycoside hydrolase (GH) family 11. The gene encoding the GH11 xylanase C (TcXylC) with the highest activity was used for overproduction and purification of the recombinant enzyme, permitting solving of the crystal structure to a resolution of 1.98 Å. In the asymmetric unit, two kinds of the crystal structures of the xylanase were identified. The main structure of the protein showed a β-jelly roll structure. We hypothesize that one of the two structures represents the open form and the other shows the close form. The changing of the flexible region between the two structures is presumed to induce and accelerate the enzyme reaction. The specificity of xylanase toward the branched xylan is discussed in the context of this structural data and by comparison with the other published structures of xylanases. PMID:25138599

  2. Biochemical evaluation of xylanases from various filamentous fungi and their application for the deinking of ozone treated newspaper pulp.

    Science.gov (United States)

    Chutani, Preeti; Sharma, Krishna Kant

    2015-01-01

    Filamentous fungi, Aspergillus oryzae MDU-4 was biochemically selected among different species of Aspergillus and Trichoderma, for xylanase production. The enzyme activity and specific activity of partially purified xylanase from A. oryzae MDU-4 was 7452 IU/ml and 13,549 IU/g, respectively. Temperature and pH optima for xylanase were found to be 60°C and 6.0, respectively. The reaction kinetics of xylanase was found to be Km (3.33 mg/ml) and Vmax (18,182 μmol/mg). The implementation of ozone treatment in the deinking of newspaper pulp resulted in high crystallinity index (72.1%) and more fibrillar surface. Furthermore, the xylanase treated pulp showed significant improvement in optical properties such as brightness (57.9% ISO) and effective residual ink concentration (211 ppm). Scanning electron microscopy analysis suggests perforations in xylanase treated pulp samples. Here we report biochemical evaluation of xylanases and a combination of ozone treatment followed by catalytically efficient fungal xylanase selected for the cost competitive deinking of newspaper pulp.

  3. Purification and preliminary characterization of a xylanase from Thermomyces lanuginosus strain SS-8.

    Science.gov (United States)

    Shrivastava, Smriti; Shukla, Pratyoosh; Mukhopadhyay, Kunal

    2011-12-01

    Thermomyces lanuginosus SS-8 was isolated from soil samples that had been collected from near self-heating plant material and its extracellular cellulase-free xylanase purified approximately 160-fold using ion exchange chromatography and continuous elution electrophoresis. This xylanase was thermoactive (optimum temperature 60 °C) at pH 6.0 and had a molecular weight of 23.79 kDa as indicated by SDS-PAGE electrophoresis. The xylanase rapidly hydrolyzed xylan directly to xylose without the production of intermediary xylo-oligosaccharides within 15 min of incubation under optimum conditions. This trait of rapidly degrading xylan to xylose as a sole end-product could have biotechnological potential in degradation of agro-wastes for bioethanol manufacturing industry. PMID:22558544

  4. Xylanases, nucleic acids encoding them and methods for making and using them

    Science.gov (United States)

    Gray, Kevin A; Dirmeier, Reinhard

    2013-07-16

    The invention relates to enzymes having xylanase, mannanase and/or glucanase activity, e.g., catalyzing hydrolysis of internal .beta.-1,4-xylosidic linkages or endo-.beta.-1,4-glucanase linkages; and/or degrading a linear polysaccharide beta-1,4-xylan into xylose. Thus, the invention provides methods and processes for breaking down hemicellulose, which is a major component of the cell wall of plants, including methods and processes for hydrolyzing hemicelluloses in any plant or wood or wood product, wood waste, paper pulp, paper product or paper waste or byproduct. In addition, methods of designing new xylanases, mannanases and/or glucanases and methods of use thereof are also provided. The xylanases, mannanases and/or glucanases have increased activity and stability at increased pH and temperature.

  5. Partial purification and characterization of xylanase produced from aspergillus niger using wheat bran

    International Nuclear Information System (INIS)

    In present exploration, purification and characterization of xylanase was carried out to find its optimum conditions for maximum functionality. The xylanase (EC 3.2.1.8) synthesized by Aspergillus niger in submerged fermentation was partially purified and characterized for different parameters like temperature, pH and heat stability. The molecular mass determined through SDS-PAGE was found 30 kDa. The specific activity of the enzyme was raised from 41.85 to 613.13 with 48.63% yield just in a two step partial purification comprising ammonium sulphate precipitation and Sephadex gel filteration column chromatography. The partially purified enzyme was found to be optimally active at 60 degree C and 7.5 pH. Conclusively, for the application of xylanase in food, feed or paper manufacturing processes, it is necessary to consider its optimum pH and temperature. (author)

  6. Production, partial purification and characterization of xylanase using Nicotiana tabacum leaf dust as substrate.

    Science.gov (United States)

    Acharya, Komal P; Shilpkar, Prateek

    2016-03-01

    Isolated Bacillus sp. was used in the present study for production of xylanase from Nicotiana tabacum leaf dust. The strain was able to give a maximum of 1.77 Uml⁻¹ xylanase activity under optimized fermentation conditions which was further increased upto 2.77 Uml⁻¹ after extraction and partial purification of enzyme. After partial purification, the enzyme was characterized and it gave the highest xylanase activity at pH 7.0, when 0.2 ml enzyme was incubated with 2.0% substrate (Nicotiana tabacum leaf dust) for 60 min at 60°C. Saccharification study of Nicotiana tabacum leaf dust with partially purified enzyme revealed that 18.4% reducing sugar was released in 20 hrs incubation, and TLC and HPTLC analysis showed that xylose and glucose sugars were obtained after hydrolysis of substrate. FTIR analysis confirmed decomposition of substrate. PMID:27097451

  7. Characterization and high expression of recombinant Ustilago maydis xylanase in Pichia pastoris.

    Science.gov (United States)

    Han, Hongjuan; You, Shuang; Zhu, Bo; Fu, Xiaoyan; Sun, Baihui; Qiu, Jin; Yu, Chengye; Chen, Lei; Peng, Rihe; Yao, Quanhong

    2015-03-01

    A recombinant xylanase gene (rxynUMB) from Ustilago maydis 521 was expressed in Pichia pastoris, and the enzyme was purified and characterized. Phylogenetic analysis demonstrated that rxynUMB belongs to glycosyl hydrolase family 11. The Trp84, Trp95, Glu93, and Glu189 residues are proposed to be present at the active site. The apparent molecular mass of the recombinant xylananse was approximately 24 kDa, and the optimum pH and temperature were 4.3 and 50 °C, respectively. Xylanase activity was enhanced by 166 and 115% with Fe(2+) and Mn(2+), respectively. The biochemical properties of this recombinant xylanase suggest that it may be a useful candidate for a variety of commercial applications.

  8. Construction of a highly active xylanase displaying oleaginous yeast: comparison of anchoring systems.

    Directory of Open Access Journals (Sweden)

    Sophie Duquesne

    Full Text Available Three Yarrowia lipolytica cell wall proteins (YlPir, YlCWP1 and YlCBM were evaluated for their ability to display the xylanase TxXYN from Thermobacillus xylanilyticus on the cell surface of Y. lipolytica. The fusion proteins were produced in Y. lipolytica JMY1212, a strain engineered for mono-copy chromosomal insertion, and enabling accurate comparison of anchoring systems. The construction using YlPir enabled cell bound xylanase activity to be maximised (71.6 U/g. Although 48% of the activity was released in the supernatant, probably due to proteolysis at the fusion zone, this system is three times more efficient for the anchoring of TxXYN than the YlCWP1 system formerly developed for Y. lipolytica. As far as we know it represents the best displayed xylanase activity ever published. It could be an attractive alternative anchoring system to display enzymes in Y. lipolytica.

  9. Study on Screening and Cultivation Conditions of Xylanase-Producing Alkalophilic Bacterial

    Institute of Scientific and Technical Information of China (English)

    Han Xiao-fang; Zheng Lian-shuang; Xie Yi-min

    2004-01-01

    An xylanase producting alkalophilic Bacillus NT-9 was obtaind by the screening method of transparent zone on the selective medium, and the effects of carbon source and nitrogen source on xylanase production were studied. The medium composed of xylose 1.5%, (NH4)2SO4 0.25%, K2HPO4 0.1%, MgSO4·7H2O 0.02%, with the initial pH of 10, was suggested to be optimal for the enzyme production in this study. When cultivatied at 37 ℃ for 72 h, the enzyme activity elaborated by the strain may reach as high as 10.5 U/mL. The xylanase produced by Bacillus NT-9 was a constituent enzyme.

  10. Exploration of Potential Actinomycetes from CIFOR Forest Origin as Antimicrobial, Antifungus, and Producing Extracellular Xylanase

    Directory of Open Access Journals (Sweden)

    Sipriyadi Sipriyadi

    2016-03-01

    Full Text Available This study aimed to isolate and explore the actinomycetes of CIFOR forest origin as an antimicrobial and antifungal agent, to produce an extracellular xylanase, and to identify isolates based on 16S rRNA gene sequences. Actinomycetes were isolated using Humic-acid Vitamin-B agar (HV media. Actinomycetes colonies that grow on the medium HV was subsequently purified by growing them on yeast malt agar (YMA media, then an antagonistic test of selected bacteria against Bacillus sp., Escherichia coli, Fusarium oxysporum, and Sclerotium sp was performed. Xylanase activity test was detected by observing a clear zone, followed by identification. Total of 35 isolates of actinomycetes isolated based on their colony morphology characteristics and diverse types of spore chains showed Streptomyces spp. of isolates CFR-06, CFR-15, CFR-17, CFR-18, and CFR-19 were able to inhibit the growth of Bacillus sp.. The highest inhibition zone has a diameter of 10.1 mm (isolate CFR-17. Isolates CFR-01 and CFR-15 were able to inhibit the growth of E. coli with the highest inhibition zone diameter of 5.1 mm (isolate CFR-15. Isolates CFR-29 and CFR-12 were able to inhibit the growth of F. oxysporum while isolate CFR-35 were able to inhibit the growth of Sclerotium sp.. Xylanase activity test showed that isolates CFR-12, CFR-20, CFR-22, CFR-24, CFR-25, CFR-30, CFR-33, CFR-34 have an ability to produce extracellular xylanase enzyme. Actinomycetes isolate (Xyl_22 as a potential xylanase enzyme producer was closely related with Streptomyces drozdowicii by the maximum similarity of 99%.How to CiteSipriyadi, S., Lestari, Y., Wahyudi, A., & Meryandini, A. (2016. Exploration Potential CIFOR Forest actinomycetes origin as Antimicrobial, Anti Fungus and Producing Enzymes Extracellular Xylanase. Biosaintifika: Journal of Biology & Biology Education, 8(1, 94-102.

  11. Purification and characterization of a thermostable hypothetical xylanase from Aspergillus oryzae HML366.

    Science.gov (United States)

    He, Haiyan; Qin, Yongling; Li, Nan; Chen, Guiguang; Liang, Zhiqun

    2015-03-01

    In the current study, fermentation broth of Aspergillus oryzae HML366 in sugar cane bagasse was subjected to ultrafiltration and ion exchange chromatography, and two xylanases, XynH1 and XynH2, were purified. Time-of-flight mass spectrometry coupled with SDS-PAGE analysis revealed that XynH1 is identical to the hypothetical A. oryzae RIB40 protein XP_001826985.1, with a molecular weight of 33.671 kDa. Likewise, XynH2 was identified as xylanase XynF1 with a molecular weight of 35.402 kDa. Sequence analysis indicated that XynH1 belongs to glycosyl hydrolases family 10. The specific activity of XynH1 was measured at 476.9 U/mg. Optimal xylanase activity was observed at pH 6.0, and enzyme remained active within pH 4.0-10.0 and at a temperature below 70 °C. Mg(2+), Mn(2+), Ca(2+), and K(+) enhanced the XynH1 xylanase activity to 146, 122, 114, and 108%, respectively. XynH1 hydrolyzed Birchwood xylan and Larchwood xylan effectively. The K m and V max of XynH1 values determined were 1.16 mM and 336 μmol/min/mg with Birchwood xylan as the substrate. A. oryzae HML366 xylanase XynH1 showed superior heat and pH tolerance, therefore may have significant applications in paper and biofuel industries. These studies constitute the first investigation of the xylanase activities of the hypothetical protein XP_001826985.1 form A. oryzae. PMID:25604952

  12. Improvement of xylanase production by Penicillium canescens 10-10c in solid-state fermentation

    Directory of Open Access Journals (Sweden)

    Thonart P.

    2008-01-01

    Full Text Available Among hemicellulases, xylanases are catalysts of considerable interest so as fundamental than applied point of view. However,it is paradoxical to note that the high cost of their production limits their use on a large scale. The use of purified xylan as culturesubstrate increases the production cost of the enzyme. Consequently, for commercial applications, it is advisable to developprocesses starting from inexpensive substrates. The purpose of this study is to optimise xylanases production in solid-statefermentation based on agricultural residues. The strain is Penicillium canescens 10-10c, selected in our laboratory for his abilityto produce xylanase activity free of cellulase. Assays concern optimization of different culture parameters in order to developin the future a solid-state fermentation reactor with soya oil cake. These parameters are: medium composition, temperatureincubation, induction and repression mechanisms. Soya oil cake in pellets (size > 10 mm gave a higher enzymatic activity.Great volume of culture medium reduced the enzymatic production. The presence of lactose, saccharose or starch of corn hasa positive effect on the production of xylanase while the presence of xylose, mannose, galactose, arabinose, cellobiose andpectin or methylcellulose reduces the production of xylanase. The sources of phosphorus (di-potassic and di-sodic enhancexylanase production. The enzymatic production obtained in Erlenmeyer flasks (250 ml after 7 days incubation at 30°C isabout 14 000 U.g-1 of carbon source. The nature of inoculum affects the enzymatic productivity. Indeed, better productivitywas obtained with inoculation by solid preculture (956 U.g-1 per day than liquid preculture (473 U.g-1 per day and sporessuspension (383 U.g-1 per day. These observed enzymatic activity levels are higher than those related in the literature, whichshows all the potentialities of this strain and this technique for the production of xylanase and allow to develop

  13. 角毛壳菌生物防治相关基因的筛选%Selection of Biocontrol-related Genes from Chaetomium cupreum

    Institute of Scientific and Technical Information of China (English)

    张海燕; 杨谦

    2007-01-01

    采用环保的生物防治技术取代传统的化学防治技术已经在植物病害防治领域中达成共识。角毛壳菌(Chaetomium cupreum)属于子囊菌亚门毛壳菌属,是一种有效的生物防治菌,对一些常见的植物病原菌的防治效果好,例如:粉红镰刀菌(Fusarium roseum)、苹果黑星菌(Venturia inequalis)、稻梨孢(Pyricularia oryzae)、灰葡萄孢(Botrytis cinerea)等。

  14. Purification and Properties of β-1, 4-Xylanase from Aeromonas caviae W-61

    OpenAIRE

    Viet, Dung Nguyen; Kamio, Yoshiyuki; Abe, Naoki; Kaneko, Jun; Izaki, Kazuo

    1991-01-01

    Aeromonas caviae W-61, which was isolated from water samples at the Faculty of Agriculture, Tohoku University, produced β-1, 4-xylanase (1,4-β-d-xylan xylanohydrolase; EC 3.2.1.8) extracellularly. The xylanase was purified to homogeneity by using DEAE-Sephadex A-50, CM-Sephadex C-50, and Sephadex G-100 column chromatographies. The molecular weight of the purified enzyme was estimated to be 22,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of the enzyme...

  15. Purification and characterization of a thermostable xylanase from Bacillus stearothermophilus T-6.

    OpenAIRE

    Khasin, A; Alchanati, I; Shoham, Y.

    1993-01-01

    Bacillus stearothermophilus T-6 produces an extracellular xylanase that was shown to optimally bleach pulp at pH 9 and 65 degrees C. The enzyme was purified and concentrated in a single adsorption step onto a cation exchanger and is made of a single polypeptide with an apparent M(r) of 43,000 (determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis). Xylanase T-6 is an endoxylanase that completely degrades xylan to xylose and xylobiose. The pIs of the purified protein were 9 a...

  16. Purification and Characterization of Haloalkaline, Organic Solvent Stable Xylanase from Newly Isolated Halophilic Bacterium-OKH

    OpenAIRE

    Sanghvi, Gaurav; Jivrajani, Mehul; Patel, Nirav; Jivrajani, Heta; Bhaskara, Govinal Badiger; Patel, Shivani

    2014-01-01

    A novel, alkali-tolerant halophilic bacterium-OKH with an ability to produce extracellular halophilic, alkali-tolerant, organic solvent stable, and moderately thermostable xylanase was isolated from salt salterns of Mithapur region, Gujarat, India. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence. Maximum xylanase production was achieved at pH 9.0 and 37°C temperature in the medium containing 15% NaCl and 1% (w/v) corn cobs. Sugarcane bagasse and whe...

  17. GH10 xylanase D from Penicillium funiculosum: biochemical studies and xylooligosaccharide production

    OpenAIRE

    Giardina Thierry; Ajandouz El-Hassan; Bonnin Estelle; Desseaux Véronique; Tauzin Alexandra; Lafond Mickael

    2011-01-01

    Abstract Background The filamentous fungus Penicillium funiculosum produces a range of glycoside hydrolases (GH). The XynD gene, encoding the sole P. funiculosum GH10 xylanase described so far, was cloned into the pPICZαA vector and expressed in methylotrophe yeast Pichia pastoris, in order to compare the results obtained with the P. funiculosum GH11 xylanases data. Results High level expression of recombinant XynD was obtained with a secretion of around 60 mg.L-1. The protein was purified to...

  18. Purification and characterization of five cellulases and one xylanase from Penicillium brasilianum IBT 20888

    DEFF Research Database (Denmark)

    Jørgensen, Henning; Eriksson, T.; Borjesson, J.;

    2003-01-01

    The filamentous fungus Penicillium brasilianum IBT 20888 was cultivated on a mixture of 30 g l(-1) cellulose and 10 g l(-1) xylan for 111 h and the resulting culture filtrate was used for protein purification. From the cultivation broth, five cellulases and one xylanase were purified. Hydrolysis...... the cellulose-binding domain or an essential part of it. The basic xylanase (pI > 9) was only active towards xylan. Two of the purified cellulases with endoglucanase activity were partly sequenced and based on sequence homology with known enzymes they were classified as belonging to families 5 and 12...

  19. PRODUCTION OF SINGLE CELL PROTEIN, ESSENTIAL AMINO ACIDS, AND XYLANASE BY PENICILLIUM JANTHINELLUM

    Directory of Open Access Journals (Sweden)

    Mala B. Rao

    2010-11-01

    Full Text Available Microbial biomass having 46% crude protein content and enriched with essential amino acids as well as extracellular xylanase activity (100-150 IU/ml was produced by an efficient fungal strain, Penicillium janthinellum (NCIM St-F-3b. Optimization studies for maximum xylanase and biomass production showed that the fungus required a simple medium containing bagasse hemicellulose as carbon source and ammonium sulphate as the nitrogen source. Therefore bagasse, which is a waste product of the sugar industry, can be efficiently used in microbioal biomass protein preparation for animal feed.

  20. PENGGUNAAN XILANASE Streptomyces sp. 45 I-3 AMOBIL UNTUK HIDROLISIS XILAN TONGKOL JAGUNG [Immobilization of Extracellular Xylanase from Streptomyces sp. 45 I-3 for Hydrolysis of Corncob Xylan

    Directory of Open Access Journals (Sweden)

    Anja Meryandini1,2*

    2009-06-01

    Full Text Available Xylan extraction from corncob is done by using alkaline as solvent. Xylan extraction from corncob could give the yields as 10.9%. One percent of corncob xylan is used as substrate to produce the xylanase, compared to oatspelt xylan. Immobilization of xylanase was performed using 1% EudragitTM S100 solution (w/v, with 5:1 volume ratio of xylanase and 1 % EudragitTM S100 (w/v. Activity of the immobilized xylanase was decreased to 23.97% compared with free xylanase. Immobilized xylanase have optimum pH and temperature at 6.0 and 40C respectively, have also thermal stability at 30–40C for an hour. Immobilized xylanase could be reused, but its activity decreased to 52.38% after 3 times application.

  1. Classification, mode of action and production strategy of xylanase and its application for biofuel production from water hyacinth.

    Science.gov (United States)

    Uday, Uma Shankar Prasad; Choudhury, Payel; Bandyopadhyay, Tarun Kanti; Bhunia, Biswanath

    2016-01-01

    Xylanases are classified under glycoside hydrolase families which represent one of the largest groups of commercial enzymes. Depolymerizing xylan molecules into monomeric pentose units involves the synergistic action of mainly two key enzymes which are endo-β-xylanase and β-xylosidase. Xylanases are different with respect to their mode of action, substrate specificities, biochemical properties, 3D structure and are widely produced by a spectrum of bacteria and fungi. Currently, large scale production of xylanase can be produced through the application of genetic engineering tool which allow fast identification of novel xylanase genes and their genetic variations makes it an ideal enzymes. Due to depletion of fossil fuel, there is urgent need to find out environment friendly and sustainable energy sources. Therefore, utilisation of cheap lignocellulosic materials along with proper optimisation of process is most important for cost efficient ethanol production. Among, various types of lignocellulosic substances, water hyacinth, a noxious aquatic weed, has been found in many tropical. Therefore, the technological development for biofuel production from water hyacinth is becoming commercially worthwhile. In this review, the classification and mode of action of xylanase including genetic regulation and strategy for robust xylanase production have been critically discussed from recent reports. In addition various strategies for cost effective biofuel production from water hyacinth including chimeric proteins design has also been critically evaluated.

  2. Production, purification and characterization of xylanase using alkalo-thermophilic Bacillus halodurans KR-1

    Directory of Open Access Journals (Sweden)

    Krityanand Kumar Mahatman

    2010-07-01

    Full Text Available Xylanase (EC. 3.2.1.8 has been isolated from an alkalo-thermophilic bacteria, Bacillus halodurans strain KR-1 isolated from the soil near river bed at Indore. The bacteria secreted xylanase in the growth medium in the presence of xylan. The production of the enzyme was induced in the presence of glucose, mannose, lactose and maltose whereas presence of starch, cellulose and sucrose retarded in enzyme production. The presence of casein, peptone, sodium nitrate and potassium nitrate as nitrogen source in the growth medium resulted in more xylanase production, whereas presence of ammonium sulfate, ammonium nitrate and yeast extract resulted in lesser enzyme production. The enzyme has been partially purified using sodium sulfate fractionation, DEAE-cellulose and Sephadex G-200 chromatographies. The molecular weight of the enzyme has been found to be 45±02 kDa as determined by Sephadex G-200 chromatography as well as sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme protein is monomeric exhibiting maximum activity at pH 9.0. The optimum temperature for exhibiting maximum activity has been found to be 40oC. The metal ions viz. Mg2+ and Fe2+ when present in the enzyme assay medium stimulated the xylanase activity, whereas Hg2+, Co2+ and Mn2+ strongly inhibited the enzyme activity. The Km value for birchwood xylan was calculated to be 12.0 g/l.

  3. Investigation of factors affecting xylanase activity from Trichoderma harzianum 1073 D3

    Directory of Open Access Journals (Sweden)

    Seyis Isil

    2005-03-01

    Full Text Available In this study, some physiological conditions affecting the activity of xylanase enzyme produced from Trichoderma harzianum 1073 D3 were determined. In addition, stabilization of pH and temperature in liquid and semi-solid state cultivation media were investigated. It was concluded that for maximum xylanase activity, incubation at 60°C in an enzyme incubation medium with pH 5 that contained 1 % xylan was appropriate. The stability studies showed that the enzyme was relatively stable in the pH range 3-7 and retained more than 50 % of its original activity after four months.Neste estudo algumas condições que afetam a atividade da enzima xylanase produzida a partir de Trichoderma harzianum 1073 D3 foram determinadas. A estabilização do pH e temperatura em cultivo líquido e semi-sólido foram avaliados. Foi concluído que para o máximo de atividade xylanase foi obtida com 1% de xylano a temperatura de 60ºC e pH 5.0. Estudos de estabilidade demonstraram que a enzima foi relativamente estável na faixa de pH entre 3-7 e retém mais do que 50% de sua atividade original após 4 meses.

  4. [Biosynthesis of cellulolytic enzymes and xylanase during submerged cultivation of the fungus Aspergillus terreus 17P].

    Science.gov (United States)

    Loginova, L G; Guzhova, E P; Ismanlova, D Iu; Burdenko, L G

    1978-01-01

    The fungus Aspergillus terreus 17P--producer of cellulolytic enzymes--was cultivated in the Biotec 10 l fermenter on the medium containing minced and heated (at 200 degrees) wheat straw aerated with a different rate. At the mixing rate of 350 rpm and aeration rate of 0.7 r/rpm on the fourth day the culture liquid was obtained whose filtrate contained an active complex of cellulolytic enzymes and xylanase: CI--3.4; APB--1.1, Cx--35.7, cellobiase--0.23, xylanase--73.8 units/ml. The fractionation of the culture liquid filtrate with ammonium sulphate showed that the fraction precipitated at an interval of saturation of 0.3--0.7 contained the largest portion of cellulolytic enzymes and xylanase. The isolated enzymic preparations had a cellulolytic and xylanase activity and contained lipase, pectinase, laminarinase. They also contained low quantities of amylase, protease, beta-1,4- and beta-1,6-glucanase. Enzymic hylrolysis by the Asp. terreus 17P preparation of straw yielded glucose and xylose, of cotton, Na-KMC, cellobiose--glucose, Xylane hydrolyzate contained xylose and arabinose.

  5. Reduction in acute ecotoxicity of paper mill effluent by sequential application of xylanase and laccase.

    Directory of Open Access Journals (Sweden)

    Saurabh Sudha Dhiman

    Full Text Available In order to reduce the ecotoxicity of paper mill, four different enzymatic pretreatment strategies were investigated in comparison to conventional chemical based processes. In strategy I, xylanase-aided pretreatment of pulp was carried out, and in strategy II, xylanase and laccase-mediator systems were used sequentially. Moreover, to compare the efficiency of Bacillus stearothermophilus xylanase and Ceriporiopsis subvermispora laccase in the reduction of ecotoxicity and pollution, parallel strategies (III and IV were implemented using commercial enzymes. Conventional C(DE(OPD(1D(2 (C(D, Cl(2 with ClO2; EOP, H2O2 extraction; D1 and D2, ClO2 and X/XLC(DE(OPD(1D(2 (X, xylanase; L, laccase sequences were employed with non-enzymatic and enzymatic strategies, respectively. Acute toxicity was determined by the extent of inhibition of bioluminescence of Vibrio fischeri with different dilutions of the effluent. Two-fold increase was observed in EC50 values for strategy I compared to the control process. On the other hand, sequential application of commercial enzymes resulted in higher acute toxicity compared to lab enzymes. In comparison to the control process, strategy II was the most efficient and successfully reduced 60.1 and 25.8% of biological oxygen demand (BOD and color of effluents, respectively. We report for the first time the comparative analysis of the ecotoxicity of industrial effluents.

  6. Reduction in acute ecotoxicity of paper mill effluent by sequential application of xylanase and laccase.

    Science.gov (United States)

    Dhiman, Saurabh Sudha; Garg, Gaurav; Sharma, Jitender; Kalia, Vipin C; Kang, Yun Chan; Lee, Jung-Kul

    2014-01-01

    In order to reduce the ecotoxicity of paper mill, four different enzymatic pretreatment strategies were investigated in comparison to conventional chemical based processes. In strategy I, xylanase-aided pretreatment of pulp was carried out, and in strategy II, xylanase and laccase-mediator systems were used sequentially. Moreover, to compare the efficiency of Bacillus stearothermophilus xylanase and Ceriporiopsis subvermispora laccase in the reduction of ecotoxicity and pollution, parallel strategies (III and IV) were implemented using commercial enzymes. Conventional C(D)E(OP)D(1)D(2) (C(D), Cl(2) with ClO2; EOP, H2O2 extraction; D1 and D2, ClO2) and X/XLC(D)E(OP)D(1)D(2) (X, xylanase; L, laccase) sequences were employed with non-enzymatic and enzymatic strategies, respectively. Acute toxicity was determined by the extent of inhibition of bioluminescence of Vibrio fischeri with different dilutions of the effluent. Two-fold increase was observed in EC50 values for strategy I compared to the control process. On the other hand, sequential application of commercial enzymes resulted in higher acute toxicity compared to lab enzymes. In comparison to the control process, strategy II was the most efficient and successfully reduced 60.1 and 25.8% of biological oxygen demand (BOD) and color of effluents, respectively. We report for the first time the comparative analysis of the ecotoxicity of industrial effluents. PMID:25058160

  7. Toevoeging van ß-glucanase en xylanase aan mengvoeders voor gespeende biggen

    NARCIS (Netherlands)

    Scholten, R.H.J.; Binnendijk, G.P.

    1997-01-01

    Op het proefbedrijf van het Proefstation voor de Varkenshouderij te Rosmalen is van november 1995 tot en met februari 1996 een onderzoek uitgevoerd om na te gaan wat de mogelijkheden zijn van toevoeging van de enzymen B-glucanase en xylanase (PorzymeSlOO@) aan biggenrantsoenen

  8. Purification and characterization of a low molecular weight xylanase from solid-state cultures of Aspergillus fumigatus Fresenius

    OpenAIRE

    Silva Claudio Henrique Cerri e; Puls Jurgen; Sousa Marcelo Valle de; Ferreira Filho Edivaldo Ximenes

    1999-01-01

    A xylan-degrading enzyme (xylanase II) was purified to apparent homogeneity from solid-state cultures of Aspergillus fumigatus Fresenius. The molecular weight of xylanase II was found to be 19 and 8.5 kDa, as estimated by SDS-PAGE and gel filtration on FPLC, respectively. The purified enzyme was most active at 55 °C and pH 5.5. It was specific to xylan. The apparent Km and Vmax values on soluble and insoluble xylans from oat spelt and birchwood showed that xylanase II was most active on solub...

  9. Isolation, Purification, and Characterization of Xylanase Produced by a New Species of Bacillus in Solid State Fermentation

    OpenAIRE

    Kamble, Rajashri D.; Jadhav, Anandrao R.

    2012-01-01

    A thermoalkalophilic new species of Bacillus, similar to Bacillus arseniciselenatis DSM 15340, produced extracellular xylanase under solid state fermentation when wheat bran is used as carbon source. The extracellular xylanase was isolated by ammonium sulfate (80%) precipitation and purified using ion exchange chromatography. The molecular weight of xylanase was ~29.8 ;kDa. The optimum temperature and pH for the enzyme activity were 50°C and pH 8.0. The enzyme was active on birchwood xylan an...

  10. Domain-swapping of mesophilic xylanase with hyper-thermophilic glucanase

    Directory of Open Access Journals (Sweden)

    Liu Liangwei

    2012-06-01

    Full Text Available Abstract Background Domain fusion is limited at enzyme one terminus. The issue was explored by swapping a mesophilic Aspergillus niger GH11 xylanase (Xyn with a hyper-thermophilic Thermotoga maritima glucanase (Glu to construct two chimeras, Xyn-Glu and Glu-Xyn, with an intention to create thermostable xylanase containing glucanase activity. Results When expressed in E. coli BL21(DE3, the two chimeras exhibited bi-functional activities of xylanase and glucanase. The Xyn-Glu Xyn moiety had optimal reaction temperature (Topt at 50 °C and thermal in-activation half-life (t1/2 at 50 °C for 47.6 min, compared to 47 °C and 17.6 min for the Xyn. The Glu-Xyn Xyn moiety had equivalent Topt to and shorter t1/2 (5.2 min than the Xyn. Both chimera Glu moieties were more thermostable than the Glu, and the three enzyme Topt values were higher than 96 °C. The Glu-Xyn Glu moiety optimal pH was 5.8, compared to 3.8 for the Xyn-Glu Glu moiety and the Glu. Both chimera two moieties cooperated with each other in degrading substrates. Conclusions Domain-swapping created different effects on each moiety properties. Fusing the Glu domain at C-terminus increased the xylanase thermostability, but fusing the Glu domain at N-terminus decreased the xylanase thermostability. Fusing the Xyn domain at either terminus increased the glucanase thermostability, and fusing the Xyn domain at C-terminus shifted the glucanase pH property 2 units higher towards alkaline environments. Fusing a domain at C-terminus contributes more to enzyme catalytic activity; whereas, fusing a bigger domain at N-terminus disturbs enzyme substrate binding affinity.

  11. Screening of xylanase activity of Streptomyces albidoflavus PSM-3n isolated from Uttarakhand

    Directory of Open Access Journals (Sweden)

    Pushpendra Sharma

    2013-07-01

    Full Text Available Background: Awareness towards the environmental pollution had made the evolution of green technology by which enzymes got special attention in industries. The enzymes replaced chemical catalysts in manufacturing various chemicals, agricultural and pharmaceutical products. Material and methods: Actinomycetes were isolated and screened for their ability to produce xylanase. For the most promising isolate, selection of media, effect of pH, temperature, metal ions, and detergents on enzyme production and activity was studied. Results: Out of 29 isolates, 22 isolates showed xylanase activity. Out of 22 xylanase producing isolate, 05 isolates were selected for secondary screening on the basis of their clear zone size. The most promising isolate PSM-3n was identified as Streptomyces albidoflavus. It produces maximum enzyme (xylanase in media Horikoshi and Ikura having carbon and nitrogen sources as oat meal and urea respectively. The optimum pH and temperature for the enzyme production was 4.0 and 45°C respectively. The enzyme activity was found maximum at temperature 50°C and enhanced in the presence of Fe3+ ions. There was a reduction in the enzyme activity in the presence of detergents like SDS, tween-20 and tween-80. The enzyme was fairly stable at 50°C for 1 h. Conclusion: The enzyme produced by the isolate PSM-3n is fairly heat stable and highly acid stable. The activity of the enzyme was increased in presence of Fe3+ ions while decreased in presence of SDS. Therefore, further studies are required for purification of xylanase for its application potential in pulp bioleaching processes and in the functional food industry.

  12. Monocentric and polycentric anaerobic fungi produce structrally related cellulases and xylanases

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xin-Liang; Chen, Huizhong; Ljungdahl, L.G. [Univ. of Georgia, Athens, GA (United States)

    1997-02-01

    Cellulase and xylanase cDNAs were isolated from a cDNA library of the polycentric anaerobic fungus Orpinomyces sp. strain PC-2 constructed in Escherichia coli. The cellulase cDNA (celB) was 1.8 kb long with an open reading frame (ORF) coding for a polypeptide of 471 amino acids, and the xylanase cDNA (xynA) was 1.2 kb long with an ORF encoding a polypeptide of 362 amino acids. Single transcripts of 1.9 kb for celB and 1.5 kb for xynA were detected in total RNA of Orpinomyces grown on Avicel. Genomic DNA regions coding for CelA and XynA were devoid of introns. The enzymes were highly homologous (80 to 85% identity) to the corresponding enzymes of the monocentric anaerobic fungus Neocallimastix patriciarum and, like those, contained in addition to a catalytic domain, a noncatalytic repeated peptide domain (NCRPD). The Orpinomyces xylanase contained one catalytic domain and thus differed from the Neocallimastix xylanase, which had two similar catalytic domains. Two peptides corresponding to the catalytic domain and the NCRPD of XynA were synthesized, and antibodies against them were raised and affinity column purified. The antibodies against the catalytic domain peptide reacted specifically with the xylanases of Orpinomyces and Neocallimastix, while the antibodies against the NCRPD reacted with many (at least eight) extracellular proteins of Orpinomyces and Neocallimastix, suggesting that the NCRPD is present in a number of polypeptides. 36 refs., 8 figs., 2 tabs.

  13. Xylanase production by Aspergillus awamori under solid state fermentation conditions on tomato pomace

    Directory of Open Access Journals (Sweden)

    Marcelo A. Umsza-Guez

    2011-12-01

    Full Text Available In this work, tomato pomace, a waste abundantly available in the Mediterranean and other temperate climates agro-food industries, has been used as raw material for the production of some hydrolytic enzymes, including xylanase, exo-polygalacturonase (exo-PG, cellulase (CMCase and α-amylase. The principal step of the process is the solid state fermentation (SSF of this residue by Aspergillus awamori. In several laboratory experiments, maximum xylanase and exo-PG activities were measured during the first days of culture, reaching values around 100 and 80 IU/gds (international units of enzyme activity per gram of dried solid, respectively. For CMCase and α-amylase production remained almost constant along fermentation, with average values of 19 and 21.5 IU/gds, respectively. Experiments carried out in a plate-type bioreactor at lab scale showed a clear positive effect of aeration on xylanase and CMCase, while the opposite was observed for exo-PG and α-amylase. In general, xylanase was the enzyme produced in higher levels, thus the optimum conditions for the determination of the enzyme activity was characterized. The xylanase activity shows an optimum pH of 5 and an optimum temperature of 50 ºC. The enzyme is activated by Mg2+, but strongly inhibited by Hg2+ and Cu2+. The enzymatic activity remains quite high if the extract is preserved in a range of pH from 3 to 10 and a temperature between 30 ºC to 40 ºC.

  14. Marine-derived fungus Aspergillus cf. tubingensis LAMAI 31: a new genetic resource for xylanase production.

    Science.gov (United States)

    Dos Santos, Juliana A; Vieira, Juliana M F; Videira, Alexandre; Meirelles, Lucas A; Rodrigues, André; Taniwaki, Marta H; Sette, Lara D

    2016-03-01

    Marine-derived fungi have been reported as relevant producers of enzymes, which can have different properties in comparison with their terrestrial counterparts. The aim of the present study was to select from a collection of 493 marine-derived fungi the best producer of xylanase in order to evaluate the enzymatic production under different conditions. A total of 112 isolates produced xylanase in solid medium containing xylan as the carbon source, with 31 of them able to produce at least 10 U/mL of the enzyme. The best production (49.41 U/mL) was achieved by the strain LAMAI 31, identified as Aspergillus cf. tubingensis. After confirming the lack of pathogenicity (absence of ochratoxin A and fumonisin B2 production) this fungus was submitted to the experimental design in order to evaluate the effect of different variables on the enzymatic production, with the aim of optimizing culture conditions. Three experimental designs (two Plackett-Burman and one factorial fractional) were applied. The best condition for the enzymatic production was defined, resulting in an increase of 12.7 times in comparison with the initial production during the screening experiments. In the validation assay, the peak of xylanase production (561.59 U/mL) was obtained after 96 h of incubation, being the best specific activity achieved after 72 h of incubation. Xylanase from A. cf. tubingensis LAMAI 31 had optimum pH and temperature at 5.0 and 55 °C, respectively, and was shown to be stable at a range of 40-50 °C, and in pH from 3.6 to 7.0. Results from the present work indicate that A. cf. tubingensis LAMAI 31 can be considered as a new genetic resource for xylanase production.

  15. Purification and characterization of a low molecular weight xylanase from solid-state cultures of Aspergillus fumigatus Fresenius

    Directory of Open Access Journals (Sweden)

    Silva Claudio Henrique Cerri e

    1999-01-01

    Full Text Available A xylan-degrading enzyme (xylanase II was purified to apparent homogeneity from solid-state cultures of Aspergillus fumigatus Fresenius. The molecular weight of xylanase II was found to be 19 and 8.5 kDa, as estimated by SDS-PAGE and gel filtration on FPLC, respectively. The purified enzyme was most active at 55 °C and pH 5.5. It was specific to xylan. The apparent Km and Vmax values on soluble and insoluble xylans from oat spelt and birchwood showed that xylanase II was most active on soluble birchwood xylan. Studies on hydrolysis products of various xylans and xylooligomers by xylanase II on HPLC showed that the enzyme released a range of products from xylobiose to xylohexaose, with a small amount of xylose from xylooligomers, and presented transferase activity.

  16. Improvement of xylanase production by Aspergillus niger XY-1 using response surface methodology for optimizing the medium composition

    Institute of Scientific and Technical Information of China (English)

    Yao-xing XU; Yan-li LI; Shao-chun XU; Yong LIU; Xin WANG; Jiang-wu TANG

    2008-01-01

    Objective: To study the optimal medium composition for xylanase production by Aspergillus niger XY-1 in solid-state fermentation (SSF). Methods: Statistical methodology including the Plackett-Burman design (PBD) and the central composite design (CCD) was employed to investigate the individual crucial component of the medium that significantly affected the enzyme yield. Results: Firstly, NaNO3, yeast extract, urea, Na2CO3, MgSO4, peptone and (NH4)2SO4 were screened as the significant factors positively affecting the xylanase production by PBD. Secondly, by valuating the nitrogen sources effect, urea was proved to be the most effective and economic nitrogen source for xylanase production and used for further optimization.Finally, the CCD and response surface methodology (RSM) were applied to determine the optimal concentration of each sig-nificant variable, which included urea, Na2CO3 and MgSO4. Subsequently a second-order polynomial was determined by mul-tiple regression analysis. The optimum values of the critical components for maximum xylanase production were obtained as follows: x1 (urea)=0.163 (41.63 g/L), x2 (Na2CO3)=-1.68 (2.64 g/L), x3 (MGSO4)=1.338 (10.68 g/L) and the predicted xylanase value was 14374.6 U/g dry substrate. Using the optimized condition, xylanase production by Aspergillus niger XY-1 after 48 h fermentation reached 14637 U/g dry substrate with wheat bran in the shake flask. Conclusion: By using PBD and CCD, we obtained the optimal composition for xylanase production by Aspergillus niger XY-1 in SSF, and the results of no additional expensive medium and shortened fermentation time for higher xylanase production show the potential for industrial utilization.

  17. Biochemical properties of xylanases from a thermophilic fungus, Melanocarpus albomyces, and their action on plant cell walls

    OpenAIRE

    Prabhu, Ashok K; Maheshwari, Ramesh

    1999-01-01

    Melanocarpus albomyces, a thermophilic fungus isolated from compost by enrichment culture in a liquid medium containing sugarcane bagasse, produced cellulase-free xylanase in culture medium. The fungus was unusual in that xylanase activity was inducible not only by hemicellulosic material but also by the monomeric pentosan unit of xylan but not by glucose. Concentration of bagasse-grown culture filtrate protein followed by size-exclusion and anion-exchange chromatography separated four xylana...

  18. Purification and properties of thermostable xylanase and beta-xylosidase produced by a newly isolated Bacillus stearothermophilus strain.

    OpenAIRE

    Nanmori, T; Watanabe, T.; Shinke, R; Kohno, A; Kawamura, Y.

    1990-01-01

    We isolated a thermophilic bacterium that produces both xylanase and beta-xylosidase. Based on taxonomical research, this bacterium was identified as Bacillus stearothermophilus. Each extracellular enzyme was separated by hydrophobic chromatography by using a Toyopearl HW-65 column, followed by gel filtration with a Sephacryl S-200 column. Each enzyme in the culture was further purified to homogeneity (62-fold for xylanase and 72-fold for beta-xylosidase) by using a fast protein liquid chroma...

  19. Research on microorganism xylanases and their applications%微生物木聚糖酶及其应用

    Institute of Scientific and Technical Information of China (English)

    高艳秀; 陈复生; 丁长河

    2012-01-01

    Xylan is the major constituent of hemicelluloses. Due to the structural heterogeneity of the xylans, xylan-degrading enzyme systems include several hydrolytic enzymes. Xylanase(EC 3.2.1.8,1,4-β-D-xylanase)can hydrolyze β-1,4-glycosidic linkages of the xylan backbone to produce short chain xylooligosacchrides of various lengths. Hence, endo-β - xylanase is the crucial enzyme component of microbial xylanolytic enzyme systems. And the microorganism xylanases system, classification, source and distribution were summarized. The microorganism xylanases including their properties, production and their applications in food, papermaking, feed industries were reviewed.%木聚糖(Xylan)是植物半纤维素的主要成分,是一种复杂的多聚五碳糖.木聚糖酶(Xylanase,EC 3.2.1.8)以内切方式作用于木聚糖主链,产生不同链长的寡糖和少量的木糖,是木聚糖降解酶系中最为关键的酶.本文综述了微生物木聚糖酶系统、微生物木聚糖酶的分类及其来源分布、微生物木聚糖酶的特性、产生及在食品、造纸、饲料行业的应用.

  20. Production, purification and characterisation of alkali stable xylanase from Cellulosimicrobium sp. MTCC 10645

    Institute of Scientific and Technical Information of China (English)

    Rajashri D Kamble; Anandrao R Jadhav

    2012-01-01

    Objective: The aim of this experimental study was production, purification and characterization of alkali stable xylanase from locally isolated Cellulosimicrobium sp. MTCC 10645, which is an important industrial enzyme used in the pulp and paper industry. Methods: The enzyme was produced in Erlenmeyer flasks containing fresh basal salt medium supplemented with 1% oat spelt xylan. The enzyme was extracted and isolated using ammonium sulphate precipitation and dialysis. It was further purified using DEAE cellulose chromatography and purity was checked by SDS-PAGE. Effect of temperature and pH on activity and stability of enzyme was studied. The enzyme was laso studied for its substrate specificity and kinetic parameters. Results: The isolate was identified on the basis of cultural, morphological, physiological and biochemical properties as well as 16S rRNA sequencing. Among the carbon sources tested, birchwood xylan found prominent for increased level of xylanase i. e. 96.33 U/ml. The enzyme was purified by DEAE cellulose chromatography at NaCl concentration of 0.25 M and had a molecular mass of 78.0 kDa. Xylanase was purified sixteen fold with a specific activity of 246.6 U/mg. Xylanase activity was maximum at 50℃. The enzyme was thermostable retaining 8%of the original activity after incubation at 60℃ of 4 h. The enzyme was active over a pH range of 6.0-11.0, although its activity was optimal at pH 7.0. About 48.52% of the enzyme activity was retained after 4 h at pH 11.0. The enzyme was active on oat spelt and birchwood xylans but not on avicel, CMC, cellobiose, starch or p-nitrophenyl xylopyranoside. The xylanase had Km and Vmax values of 4.76 mg/ml and 232.5 μmol/min/mg, respectively when birchwood xylan used as substrate. Conclusions:The xylanase showed a unique pattern of xylan hydrolysis releasing a large amount of intermediate products (xylotriose and xylobiose) with small quantity of xylose. Some of these characteristics make this enzyme potentially

  1. Paddy Husk as Support for Solid State Fermentation to Produce Xylanase from Bacillus pumilus

    Institute of Scientific and Technical Information of China (English)

    Ranganathan KAPILAN; Vasanthy ARASARATNAM

    2011-01-01

    To optimize culture conditions for xylanase production by solid state fermentation (SSF) using Bacillus pumilus,with paddy husk as support,solid medium contained 200 g of paddy husk with 800 mL of liquid fermentation medium [xylan,20.0 g/L; peptone,2.0 g/L; yeast extract,2.5 g/L; K2HPO4,2.5 g/L; KH2PO4,1.0 g/L; NaCl,0.1 g/L; (NH4)2SO4,2.0 g/L,CaCl22H2O,0.005 g/L; MgCl2·6H2O,0.005 g/L; and FeCl3,0.005 g/L] at pH 9.0 was applied.The highest xylanase activity (142.0 +0.47 U/g DM] was obtained on the 6th day at 30℃.The optimized paddy husk to liquid fermentation medium ratio was 2∶9,and the optimized culture temperature was 40℃.When commercial Birchwood xylan was replaced with different concentrations of corncob,xylanase production was maximized (224.2 U/g DM) in the medium with 150 g/L corncob.Xylanase production was increased by sucrose,fructose and arabinose,whereas reduced by glucose,galactose,lactose and amylose.When organic nitrogen sources were replaced with locally available nitrogen sources such as groundnut powder or sesame seedcake powder or coconut seedcake powder or soy meal powder,the highest xylanase production (290.7 U/g DM) was obtained in the medium with soy meal powder and 16.0 g/L of soy meal powder was the optimum (326.5±0.34 U/g DM).Based on the optimization studies,B.pumilus produced 2.3 times higher xylanase activity.The medium cost was reduced from 2 458.3 to 178.3 SLR/kg and the total activity which could be obtained from 1 kg of the medium was increased from 48 624 to 220 253 Units.

  2. Cloning of xylanase gene of Streptomyces flavogriseus in Escherichia coli and bacteriophage lambda-induced lysis for the release of cloned enzyme.

    Science.gov (United States)

    Srivastava, R; Ali, S S; Srivastava, B S

    1991-03-01

    The xylanase gene of Streptomyces flavogriseus was cloned in pUC8 plasmid and expressed in Escherichia coli lysogenic for lambda cI857. lambda-Induced lysis of E. coli at 42 degrees C allowed efficient release of cloned enzyme activity in extracellular environment. The xylanase gene was located in the 0.8-kb HindIII fragment and coded for 18,000 Mr xylanase.

  3. Novel xylanases from Simplicillium obclavatum MTCC 9604: comparative analysis of production, purification and characterization of enzyme from submerged and solid state fermentation

    OpenAIRE

    Roy, Saugata; Dutta, Tanmay; Sarkar, Tuhin Subhra; Ghosh, Sanjay

    2013-01-01

    The production of extracellular xylanase by a newly isolated fungus Simplicillium obclavatum MTCC 9604 was studied in solid-state and submerged fermentation. Multiple xylanases and endoglucanases were produced by the strain during growth on wheat bran in solid state fermentation (SSF). A single xylanase isoform was found to be produced by the same fungus under submerged fermentation (SF) using wheat bran as sole carbon source. Enzyme activity, stability and the protein yield were much higher ...

  4. The expression of a xylanase targeted to ER-protein bodies provides a simple strategy to produce active insoluble enzyme polymers in tobacco plants.

    Directory of Open Access Journals (Sweden)

    Immaculada Llop-Tous

    Full Text Available BACKGROUND: Xylanases deserve particular attention due to their potential application in the feed, pulp bleaching and paper industries. We have developed here an efficient system for the production of an active xylanase in tobacco plants fused to a proline-rich domain (Zera of the maize storage protein γ-zein. Zera is a self-assembling domain able to form protein aggregates in vivo packed in newly formed endoplasmic reticulum-derived organelles known as protein bodies (PBs. METHODOLOGY/PRINCIPAL FINDINGS: Tobacco leaves were transiently transformed with a binary vector containing the Zera-xylanase coding region, which was optimized for plant expression, under the control of the 35S CaMV promoter. The fusion protein was efficiently expressed and stored in dense PBs, resulting in yields of up to 9% of total protein. Zera-xylanase was post-translationally modified with high-mannose-type glycans. Xylanase fused to Zera was biologically active not only when solubilized from PBs but also in its insoluble form. The resistance of insoluble Zera-xylanase to trypsin digestion demonstrated that the correct folding of xylanase in PBs was not impaired by Zera oligomerization. The activity of insoluble Zera-xylanase was enhanced when substrate accessibility was facilitated by physical treatments such as ultrasound. Moreover, we found that the thermostability of the enzyme was improved when Zera was fused to the C-terminus of xylanase. CONCLUSION/SIGNIFICANCE: In the present work we have successfully produced an active insoluble aggregate of xylanase fused to Zera in plants. Zera-xylanase chimeric protein accumulates within ER-derived protein bodies as active aggregates that can easily be recovered by a simple density-based downstream process. The production of insoluble active Zera-xylanase protein in tobacco outlines the potential of Zera as a fusion partner for producing enzymes of biotechnological relevance. Zera-PBs could thus become efficient and low

  5. Emerging role of N- and C-terminal interactions in stabilizing (β/α8 fold with special emphasis on Family 10 xylanases

    Directory of Open Access Journals (Sweden)

    Amit Bhardwaj

    2012-09-01

    Full Text Available Xylanases belong to an important class of industrial enzymes. Various xylanases have been purified and characterized from a plethora of organisms including bacteria, marine algae, plants, protozoans, insects, snails and crustaceans. Depending on the source, the enzymatic activity of xylanases varies considerably under various physico-chemical conditions such as temperature, pH, high salt and in the presence of proteases. Family 10 or glycosyl hydrolase 10 (GH10 xylanases are one of the well characterized and thoroughly studied classes of industrial enzymes. The TIM-barrel fold structure which is ubiquitous in nature is one of the characteristics of family 10 xylanases. Family 10 xylanases have been used as a “model system” due to their TIM-barrel fold to dissect and understand protein stability under various conditions. A better understanding of structure-stability-function relationships of family 10 xylanases allows one to apply these governing molecular rules to engineer other TIM-barrel fold proteins to improve their stability and retain function(s under adverse conditions. In this review, we discuss the implications of N-and C-terminal interactions, observed in family 10 xylanases on protein stability under extreme conditions. The role of metal binding and aromatic clusters in protein stability is also discussed. Studying and understanding family 10 xylanase structure and function, can contribute to our protein engineering knowledge.

  6. Industrial textile effluent decolourization in stirred and static batch cultures of a new fungal strain Chaetomium globosum IMA1 KJ472923.

    Science.gov (United States)

    Manai, Imène; Miladi, Baligh; El Mselmi, Abdellatif; Smaali, Issam; Ben Hassen, Aida; Hamdi, Moktar; Bouallagui, Hassib

    2016-04-01

    The treatment of an industrial textile effluent (ITE) was investigated by using a mono-culture of a novel fungal strain Chaetomium globosum IMA1. This filamentous fungus was selected based on its capacity for dye removal via the biodegradation mechanism. The respirometric analysis showed that C. globosum IMA1 was resistant to an indigo concentration up to 700 mg equivalent COD/L. The decolourization of the ITE by C. globosum was performed in static and stirred batch systems. The better lignin peroxidase (LiP), laccase and the manganese peroxidase (MnP) productions were 829.9 U/L, 83 U/L and 247.8 U/L, respectively since 3-5 days under a stirred condition. Therefore, the chemical oxygen demand (COD) and colors (OD620) removal yields reached 88.4% and 99.8%, respectively. Fourier transforms infrared spectroscopy (FTIR) analysis of the treated effluent showed that the decolourization was due to the degradation and the transformation of dye molecules. However, spectrophotometric examination showed that the complete dye removal was through fungal adsorption (8%), followed by degradation (92%). PMID:26775156

  7. Industrial textile effluent decolourization in stirred and static batch cultures of a new fungal strain Chaetomium globosum IMA1 KJ472923.

    Science.gov (United States)

    Manai, Imène; Miladi, Baligh; El Mselmi, Abdellatif; Smaali, Issam; Ben Hassen, Aida; Hamdi, Moktar; Bouallagui, Hassib

    2016-04-01

    The treatment of an industrial textile effluent (ITE) was investigated by using a mono-culture of a novel fungal strain Chaetomium globosum IMA1. This filamentous fungus was selected based on its capacity for dye removal via the biodegradation mechanism. The respirometric analysis showed that C. globosum IMA1 was resistant to an indigo concentration up to 700 mg equivalent COD/L. The decolourization of the ITE by C. globosum was performed in static and stirred batch systems. The better lignin peroxidase (LiP), laccase and the manganese peroxidase (MnP) productions were 829.9 U/L, 83 U/L and 247.8 U/L, respectively since 3-5 days under a stirred condition. Therefore, the chemical oxygen demand (COD) and colors (OD620) removal yields reached 88.4% and 99.8%, respectively. Fourier transforms infrared spectroscopy (FTIR) analysis of the treated effluent showed that the decolourization was due to the degradation and the transformation of dye molecules. However, spectrophotometric examination showed that the complete dye removal was through fungal adsorption (8%), followed by degradation (92%).

  8. Cloning and expression of an endo-1,4-β-xylanase from the coffee berry borer, Hypothenemus hampei

    Directory of Open Access Journals (Sweden)

    Padilla-Hurtado Beatriz

    2012-01-01

    Full Text Available Abstract Background The coffee berry borer, Hypothenemus hampei, reproduces and feeds exclusively on the mature endosperm of the coffee seed, which has a cell wall composed mainly of a heterogeneous mixture of hemicellulose polysaccharides, including arabinoxylans. Xylanases are digestive enzymes responsible for the degradation of xylan based polymers, hydrolyzing them into smaller molecules that are easier to assimilate by insects. We report the cloning, expression and enzymatic characterization of a xylanase gene that was identified in the digestive tract of the coffee berry borer. Methods The complete DNA sequence encoding a H. hampei xylanase (HhXyl was obtained using a genome walking technique in a cDNA library derived from the borer digestive tract. The XIP-I gene was amplified from wheat (Triticum aestivum variety Soisson. A Pichia pastoris expression system was used to express the recombinant form of these enzymes. The xylanase activity and XIP-I inhibitory activity was quantified by the 3,5-dinitrosalicylic (DNS. The biological effects of XIP-I on borer individuals were evaluated by providing an artificial diet enriched with the recombinant XIP-I protein to the insects. Results The borer xylanase sequence contains a 951 bp open reading frame that is predicted to encode a 317-amino acid protein, with an estimated molecular weight of 34.92 kDa and a pI of 4.84. Bioinformatic analysis revealed that HhXyl exhibits high sequence homology with endo-β-D-xylanases of Streptomyces bingchenggensis from glycosyl hydrolase 10 (GH10. The recombinant xylanase showed maximal activity at pH 5.5 and 37°C. XIP-I expressed as a recombinant protein inhibited HhXyl activity in vitro and caused individual H. hampei mortality in bioassays when included as a supplement in artificial diets. Conclusion A xylanase from the digestive tract of the coffee berry borer was identified and functionally characterized. A xylanase inhibitor protein, XIP-I, from wheat was

  9. Pseudomonas sp. xylanase for clarification of Mausambi and Orange fruit juice

    Science.gov (United States)

    Sharma, Pawan Kumar; Chand, Duni

    2012-07-01

    Xylanase can be usd for many Industrial applications and juice clarification is one of them. Pseudomonas sp. xylanase was used for fruit juice clarification in free State. Maximum amount of juice clarification was in case of Mausambi juice was observed at 40 C∞ and 52 hours, in case of free enzyme treated juice there is 46.9% increase in clarity and 1.7 fold increase in reducing sugars of the juice and enzyme dose was optimized as 8U with maximum flow rate of 6 ml/min at this dose. In case of orange juice in free enzyme treated juice maximum clarity was observed at 40 C∞ and 52 hours, juice was found to be 42.14 % clear with increase of 1.9 fold of reducing sugars, enzyme dose optimized was 8.06U with maximum flow rate of 0.86 ml/min.

  10. Cloning, overexpression, and characterization of a novel alkali-thermostable xylanase from Geobacillus sp. WBI.

    Science.gov (United States)

    Mitra, Suranjita; Mukhopadhyay, Bidhan Chandra; Mandal, Anisur Rahaman; Arukha, Ananta Prasad; Chakrabarty, Kuheli; Das, Gourab Kanti; Chakrabartty, Pran Krishna; Biswas, Swadesh Ranjan

    2015-04-01

    An endo-β-1,4-xylanase gene xynA of a thermophilic Geobacillus sp. WBI from "hot" compost was isolated by PCR amplification. The gene encoding 407 residues were overexpressed in E. coli and purified by Ni-NTA chromatography. The purified enzyme (47 kDa) had a broad pH optimum of 6.0 to 9.0, and was active between 50 and 90 °C. The enzyme retained 100% of its activity when incubated at 65 °C for 1 h under alkaline condition (pH 10.0) and retained 75% activity at pH 11.0. The K(m) and V(max) of the enzyme were 0.9 mg ml(-1) and 0.8 µmol ml(-1) min(-1), respectively. In molecular dynamics simulation at 338 K (65 °C), the enzyme was found to be stable. At an elevated temperature (450 K) specific α-helix and β-turns of the proteins were most denatured. The denaturation was less in WBI compared with its highest homolog G. stearothermophilus T-6 xylanase with difference of six residues. The results predict that these regions are responsible for the improved thermostability observed over related enzymes. The present work encourages further experimental demonstration to understand how these regions contribute thermostability to WBI xylanase. The study noted that WBI produces a xylanase with unique characteristics, specifically alkali-thermostability.

  11. Biosynthesis, purification and characterization of endoglucanase from a xylanase producing strain Aspergillus niger B03

    OpenAIRE

    Georgi Todorov Dobrev; Boriana Yordanova Zhekova

    2012-01-01

    An extracellular endoglucanase was isolated from the culture liquid of xylanase producing strain Aspergillus niger B03. The enzyme was purified to a homogenous form, using consecutive ultrafiltration, anion exchange chromatography, and gel filtration. Endoglucanase was a monomer protein with a molecular weight of 26,900 Da determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 28,800 Da determined by gel filtration. The optimal pH and temperature values for the enzyme ac...

  12. Screening of xylanase activity of Streptomyces albidoflavus PSM-3n isolated from Uttarakhand

    OpenAIRE

    Pushpendra Sharma; Vijay Kumar; Bindu Naik; Gajraj Singh Bisht

    2013-01-01

    Background: Awareness towards the environmental pollution had made the evolution of green technology by which enzymes got special attention in industries. The enzymes replaced chemical catalysts in manufacturing various chemicals, agricultural and pharmaceutical products. Material and methods: Actinomycetes were isolated and screened for their ability to produce xylanase. For the most promising isolate, selection of media, effect of pH, temperature, metal ions, and detergents on enzyme pro...

  13. Effects of disruption of xylanase-encoding genes on the xylanolytic system of Streptomyces lividans.

    Science.gov (United States)

    Arhin, F F; Shareck, F; Kluepfel, D; Morosoli, R

    1994-01-01

    Wild-type Streptomyces lividans produced the three xylanases (XlnA, XlnB, and XlnC) when xylan, xylan hydrolysates obtained by the action of XlnA, XlnB, and XlnC, or purified small xylo-oligosaccharides (xylobiose [X2], xylotriose [X3], xylotetraose [X4], and xylopentaose [X5]) were used as the carbon source. The three xylanase genes of S. lividans (xlnA, xlnB, and xlnC) were disrupted by using vectors that integrate into the respective genes. Disruption of one or more of the xln genes resulted in reduced growth rates and reduced total xylanase activities when the strain was grown in xylan. The greatest effect was observed when xlnA was disrupted. In medium containing xylan, disruption of xlnA did not affect expression of xlnB and xlnC; disruption of xlnB did not affect expression of xlnA but affected expression of xlnC; and disruption of xlnC did not affect expression of xlnA but affected expression of xlnB. A fraction of XlnB or XlnC hydrolytic products (those with a degree of polymerization greater than 11 [X11]) was found to stimulate expression of xlnB and xlnC in strains disrupted in xlnC and xlnB, respectively, whereas lower-molecular-weight fractions as well as purified small xylo-oligosaccharides did not. The stimulating molecule(s) lost its effect when it was hydrolyzed further by XlnA. A mechanism of transglycosylation reactions by the S. lividans xylanases is postulated to be involved in the regulation of xln genes. Images PMID:8051006

  14. Ultrasounds pretreatment of olive pomace to improve xylanase and cellulase production by solid-state fermentation

    OpenAIRE

    Leite, A; Salgado, José Manuel; Venâncio, Armando; Domínguez, José Manuel; Belo, Isabel

    2016-01-01

    Abstract Olive mills generate a large amount of waste that can be revaluated. This work aim to improve the production lignocellulolytic enzymes by solid-state fermentation using ultrasounds pretreated olive mill wastes. The composition of olive mill wastes (crude and exhausted olive pomace) was compared and several physicochemical characteristics were significantly different. The use of both wastes in SSF was evaluated and a screening of fungi for xylanase and cellulase production was carried...

  15. Two New Xylanases with Different Substrate Specificities from the Human Gut Bacterium Bacteroides intestinalis DSM 17393

    KAUST Repository

    Hong, Pei-Ying

    2014-01-24

    Xylan is an abundant plant cell wall polysaccharide and is a dominant component of dietary fiber. Bacteria in the distal human gastrointestinal tract produce xylanase enzymes to initiate the degradation of this complex heteropolymer. These xylanases typically derive from glycoside hydrolase (GH) families 10 and 11; however, analysis of the genome sequence of the xylan-degrading human gut bacterium Bacteroides intestinalis DSM 17393 revealed the presence of two putative GH8 xylanases. In the current study, we demonstrate that the two genes encode enzymes that differ in activity. The xyn8A gene encodes an endoxylanase (Xyn8A), and rex8A encodes a reducing-end xylose-releasing exo-oligoxylanase (Rex8A). Xyn8A hydrolyzed both xylopentaose (X5) and xylohexaose (X6) to a mixture of xylobiose (X2) and xylotriose (X3), while Rex8A hydrolyzed X3 through X6 to a mixture of xylose (X1) and X2. Moreover, rex8A is located downstream of a GH3 gene (xyl3A) that was demonstrated to exhibit β-xylosidase activity and would be able to further hydrolyze X2 to X1. Mutational analyses of putative active site residues of both Xyn8A and Rex8A confirm their importance in catalysis by these enzymes. Recent genome sequences of gut bacteria reveal an increase in GH8 Rex enzymes, especially among the Bacteroidetes, indicating that these genes contribute to xylan utilization in the human gut.

  16. Optimal secretion of alkali-tolerant xylanase in Bacillus subtilis by signal peptide screening.

    Science.gov (United States)

    Zhang, Weiwei; Yang, Mingming; Yang, Yuedong; Zhan, Jian; Zhou, Yaoqi; Zhao, Xin

    2016-10-01

    Xylanases are industrially important enzymes for xylan digestion. We experimentally screened over 114 Sec and 24 Tat pathway signal peptides, with two different promoters, for optimal production of an alkaline active xylanase (XynBYG) from Bacillus pumilus BYG in a Bacillus subtilis host. Though both promoters yielded highly consistent secretion levels (0.97 Pearson correlation coefficient), the Sec pathway was found to be more efficient than the Tat pathway for XynBYG secretion. Furthermore, the optimal signal peptide (phoB) for XynBYG secretion was found to be different from the optimal peptides for cutinase and esterase reported in previous studies. A partial least squares regression analysis further identified several statistically important variables: helical properties, amino acid composition bias, and the discrimination score in Signal P. These variables explain the observed 23 % variance in the secretion yield of XynBYG by the different signal peptides. The results also suggest that the helical propensity of a signal peptide plays a significant role in the beta-rich xylanase, but not in the helix-rich cutinase, suggesting a coupling of the conformations between the signal peptide and its cargo protein for optimal secretion. PMID:27225471

  17. The influence of sorbitol on the production of cellulases and xylanases in an airlift bioreactor.

    Science.gov (United States)

    Ritter, Carla Eliana Todero; Fontana, Roselei Claudete; Camassola, Marli; da Silveira, Maurício Moura; Dillon, Aldo José Pinheiro

    2013-11-01

    The production of cellulases and xylanases by Penicillium echinulatum in an airlift bioreactor was evaluated. In batch production, we tested media with isolated or associated cellulose and sorbitol. In fed-batch production, we tested cellulose addition at two different times, 30 h and 48 h. Higher liquid circulation velocities in the downcomer were observed in sorbitol 10 g L(-1) medium. In batch production, higher FPA (filter paper activity) and endoglucanase activities were obtained with cellulose (7.5 g L(-1)) and sorbitol (2.5 g L(-1)), 1.0 U mL(-1) (120 h) and 6.4 U m L(-1) (100 h), respectively. For xylanases, the best production condition was cellulose 10 g L(-1), which achieved 5.5 U mL(-1) in 64 h. The fed-batch process was favorable for obtaining xylanases, but not for FPA and endoglucanases, suggesting that in the case of cellulases, the inducer must be added early in the process.

  18. Ultrasounds pretreatment of olive pomace to improve xylanase and cellulase production by solid-state fermentation.

    Science.gov (United States)

    Leite, Paulina; Salgado, José Manuel; Venâncio, Armando; Domínguez, José Manuel; Belo, Isabel

    2016-08-01

    Olive mills generate a large amount of waste that can be revaluated. This work aim to improve the production lignocellulolytic enzymes by solid-state fermentation using ultrasounds pretreated olive mill wastes. The composition of olive mill wastes (crude and exhausted olive pomace) was compared and several physicochemical characteristics were significantly different. The use of both wastes in SSF was evaluated and a screening of fungi for xylanase and cellulase production was carried out. After screening, the use of exhausted olive pomace and Aspergillus niger led to the highest enzyme activities, so that they were used in the study of ultrasounds pre-treatment. The results showed that the sonication led to a 3-fold increase of xylanase activity and a decrease of cellulase activity. Moreover, the liquid fraction obtained from ultrasounds treatment was used to adjust the moisture of solid and a positive effect on xylanase (3.6-fold increase) and cellulase (1.2-fold increase) production was obtained. PMID:27209456

  19. Novel alkali-thermostable xylanase from Thielaviopsis basicola (MTCC 1467): Purification and kinetic characterization.

    Science.gov (United States)

    Goluguri, Baby Rani; Thulluri, Chiranjeevi; Addepally, Uma; Shetty, Prakasham Reddy

    2016-01-01

    A novel extracellular alkali-thermostable xylanase was purified to an apparent homogeneity from the submerged fermented culture filtrate of Thielaviopsis basicola MTCC 1467, wherein, the fungus was fed with rice straw as prime carbon source. SDS-PAGE analysis of the xylanase showcased molecular weight of ∼ 32 kDa. This extracellular protein macromolecule had maximum xylanolytic activity at pH 5.5 and 60°C, and was stable in the range of pH 5.0-10.0 for 5 days retaining >70% activity. The enzyme was stable at 30-50°C for 5h retaining >85% activity and further by retaining 70% activity at 60°C for 2h. The enzyme deactivation constants (kd) were in range of 0.41-1.3. The kinetic experiments specified that the enzyme had Km and Vmax values of 1.447 ± 0.22 mg mL(-1) and 60.04 ± 1.25 IU mL(-1), respectively, for xylan. The purified xylanase was significantly inhibited by Cu(2+) and Zn(2+) (∼ 58%), whilst Ca(2+) and Na(+) ions displayed partial inhibition (<8%) Intriguingly, the K(+) and Mn(2+) ions enhanced the activity by about ∼ 10%. Both SDS and EDTA reduced its activity by ∼ 20%. PMID:26526179

  20. Low-cost carbon sources for the production of a thermostable xylanase by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Elias Pião Benedetti

    2013-01-01

    Full Text Available A strain of the filamentous fungus Aspergillus niger was isolated and shown to possess extracellular xylanolytic activity. These enzymes have biotechnological potential and can be employed in various industries. This fungus produced its highest xylanase activity in a medium made up of 0.1% CaCO3 , 0.5% NaCl, 0.1% NH4 Cl, 0.5% corn steep liquor and 1% carbon source, at pH 8.0. A lowcost hemicellulose residue (powdered corncob proved to be an excellent inducer of the A. niger xylanolytic complex. Filtration of the crude culture medium with suspended kaolin was ideal for to clarify the extract and led to partial purification of the xylanolytic activity. The apparent molecular mass of the xylanase was about 32.3 kDa. Maximum enzyme activity occurred at pH 5.0 and 55-60ºC. Apparent Km was 10.41 ± 0.282 mg/mL and Vmax was 3.32 ± 0.053 U/mg protein, with birchwood xylan as the substrate. Activation energy was 4.55 kcal/mol and half-life of the crude enzyme at 60ºC was 30 minutes. Addition of 2% glucose to the culture medium supplemented with xylan repressed xylanase production, but in the presence of xylose the enzyme production was not affected.

  1. Computational design of an endo-1,4-[beta]-xylanase ligand binding site

    Energy Technology Data Exchange (ETDEWEB)

    Morin, Andrew; Kaufmann, Kristian W.; Fortenberry, Carie; Harp, Joel M.; Mizoue, Laura S.; Meiler, Jens (Vanderbilt)

    2012-09-05

    The field of computational protein design has experienced important recent success. However, the de novo computational design of high-affinity protein-ligand interfaces is still largely an open challenge. Using the Rosetta program, we attempted the in silico design of a high-affinity protein interface to a small peptide ligand. We chose the thermophilic endo-1,4-{beta}-xylanase from Nonomuraea flexuosa as the protein scaffold on which to perform our designs. Over the course of the study, 12 proteins derived from this scaffold were produced and assayed for binding to the target ligand. Unfortunately, none of the designed proteins displayed evidence of high-affinity binding. Structural characterization of four designed proteins revealed that although the predicted structure of the protein model was highly accurate, this structural accuracy did not translate into accurate prediction of binding affinity. Crystallographic analyses indicate that the lack of binding affinity is possibly due to unaccounted for protein dynamics in the 'thumb' region of our design scaffold intrinsic to the family 11 {beta}-xylanase fold. Further computational analysis revealed two specific, single amino acid substitutions responsible for an observed change in backbone conformation, and decreased dynamic stability of the catalytic cleft. These findings offer new insight into the dynamic and structural determinants of the {beta}-xylanase proteins.

  2. Partial purification and characterization of Xylanase from Trichoderma viride produced under SSF

    Directory of Open Access Journals (Sweden)

    M Irfan

    2012-03-01

    Full Text Available Summary: In the present study xylanase enzyme was produced from Trichoderma viride in solid state fermentation using sugarcane bagasse as a substrate. The whole fermentation process was carried out in 250ml Erlenmeyer flask at 30oC for seven days of fermentation period. The enzyme was partially purified by ammonium sulphate (60% fractionation followed by dialysis. The partially purified enzyme was further characterized showing optimum pH and temperature of 5.0 and 50oC respectively. Metal profile of the enzyme showed that it was stimulated by FeSO4 (134%, CaCl2 (129%, BaCl2 (105%, MgSO4 (113%, MnCl2 (102% or AgCl (107% and it was strongly inhibited by EDTA (26% or HgSO4 (32%. Industrial Relevance: In the present study, xylanase enzyme was produced and characterized from Trichoderma viride in solid state fermentation using cheap substrate. This enzyme is very helpful in industrial sector especially in pulp and paper industry, food industry and also in bioethanol production. Pilot scale production of this enzyme in industries can reduce the import cost of the enzyme and make the whole process cost effective. Keywords: Partial purification; Characterization; Xylanase; Trichoderma viride; SSF

  3. Xylanase production by a thermo-tolerant Bacillus species under solid-state and submerged fermentation

    Directory of Open Access Journals (Sweden)

    Uma Gupta

    2009-12-01

    Full Text Available Effects of xylose on xylanase production by a thermophilic Bacillus sp showed diverse patterns on corn cob (CC and wheat bran (WB as sole carbon sources in solid- state fermentation (SSF and submerged fermentation (SmF. Supplementation of these media with either mineral salt solution (MSS or yeast extract peptone (YEP also exerted variable effects. While under SSF, xylose stimulated xylanase synthesis by 44.01%, on wheat bran supplemented with MSS, it decreased the enzyme activity by 12.89% with YEP supplementation. In SmF, however the enzyme synthesis was stimulated by xylose on supplementation with both MSS and YEP by 41.38% and 27.47%, respectively. On corn cob under SSF, xylose repression was significant both with MSS (26.92% and YEP (23.90% supplementation. Repression by xylose also took place on corn cob and YEP (19.69% under SmF, while significant stimulation (28.55% was observed by MSS supplementation. The possible role of media composition and fermentation conditions in the regulation of xylanase synthesis by xylose is discussed.

  4. Does release of encapsulated nutrients have an important role in the efficacy of xylanase in broilers?

    Science.gov (United States)

    Khadem, A; Lourenço, M; Delezie, E; Maertens, L; Goderis, A; Mombaerts, R; Höfte, M; Eeckhaut, V; Van Immerseel, F; Janssens, G P J

    2016-05-01

    The non-starch polysaccharides (NSPs) in cell walls can act as a barrier for digestion of intracellular nutrients. This effect is called "cage effect." Part of the success of fibrolytic enzymes in broiler feed is assumed to be attributed to cage effect reduction. Further, changes in viscosity and potential prebiotic action should also be considered. The aim of this study was to gain insight into the relative importance of the cage effect in xylanase efficacy in broilers. Using a 2×2 factorial design, 24 pens with 30 Ross 308 male chicks were fed corn-soy based diets consisting of normal and freeze-thawed (5 d at -18°C) corn, both with and without xylanase. The freeze-thaw method was used to eliminate the cage effect, whereas a corn-based diet was used to exclude viscosity effects. Body weights (BW), feed intake (FI), and feed conversion ratio (FCR) were determined at d 13, 26, and 39. A balance study was executed at the end of the growing phase. These birds were euthanized at d 34 (non-fasted) to determine the viscosity of digesta, blood metabolites, intestinal morphology, and microbiota composition. During the finisher period, there was a significant interaction between enzyme supplementation and freeze-thawing for FCR, in which FCR was improved by freeze-thawed corn and tended to be improved by normal corn+enzyme compared with the control group. The improvement in performance (finisher period) of freeze-thawed corn and xylanase coincided with increased gut absorption of glucose (based on postprandial plasma concentrations) and increased number of Clostridiumcluster IV in the caecum, and agreed with the higher gut villus height. In addition, xylanase inclusion significantly increased the postprandial plasma glycine and triglycerides concentration, and led to elevated bacterial gene copies of butyryl CoA:acetate CoA-transferase, suggesting a prebiotic effect of xylanase addition through more than just the cage effect reduction. The applied model managed to rule

  5. The influence of some factors on β-1,4-xylanase activity of the filamentous fungus Trichoderma reesei QM9414

    Directory of Open Access Journals (Sweden)

    Alexandru Manoliu

    2012-03-01

    Full Text Available The mesophyllic fungus Trichoderma reesei (anamorph to Hypocrea jecorina is an important biotechnological tool, known for its ability to secrete large quantities of hydrolytic enzymes. Renewable biomass, such as agricultural and forest wastes are used to produce microbial enzymes in various industrial processes such as food, feed and bioethanol industries. In raw biomass materials, such as wheat straws, barley straws and maize stalks, the main polysaccharide is cellulose which is closely associated with hemicelluloses like xylan, manan and xyloguclan. In consequence, the hydrolysis of these materials requires the concerted action of several enzymes, namely cellulases and xylanases. Endo-xylanase (endo-1,4--xylanase, EC 3.2.1.8 is the key enzyme involved in xylan hydrolysis, the mainhemicellulosic component of plant cell walls. The metabolic activity and enzyme productivity of Trichoderma reesei isinfluenced by various environmental conditions. In this context, we analysed the effect of pH, cultivation period, thenature of the substrate used and the nitrogen source on enzymatic activity. The maximum xylanase yield was recorded at a initial pH of 4 (116.189 IU/ml for barley and 5 for wheat (88.578 IU/ml, respectively maize (116.583 IU/ml. The bestsubstrate for endo-xylanase activity was maize stalks (90.446 IU/ml at a a concentration of 30g/L.

  6. Production of Xylanase from Arthrobacter sp. MTCC 6915 Using Saw Dust As Substrate under Solid State Fermentation

    Directory of Open Access Journals (Sweden)

    Sevanan Murugan

    2011-01-01

    Full Text Available Saw dust was used as substrate for xylanase production from Arthrobacter sp. MTCC 6915. The study of period of incubation, temperature, pH, carbon, and nitrogen sources for xylanase production was optimized. Xylanase production was found to be optimum at an incubation period of 96 hrs (117.0 U/mL, temperature 30°C (105.0 U/mL, and pH 9.0 (102.9 U/mL. The results showed that the xylanase production was found to be higher in the presence of carboxymethylcellulose (176.4 U/mL and dextrose (126.0 U/mL. It was also observed that peptone (170.1 U/mL and beef extract (161.7 U/mL supported maximum xylanase production.The enzyme was characterized and found to be fairly active at pH 9 (764.4 U/mL and temperature 60°C (819 U/mL. Even in the present study, a major difference in the production temperature (30°C and optimal temperature (60°C of the enzyme activity was observed. However, the pH of the production media and the enzyme activity were found to be the same (pH 9.

  7. The Botrytis cinerea xylanase Xyn11A contributes to virulence with its necrotizing activity, not with its catalytic activity

    Directory of Open Access Journals (Sweden)

    González Celedonio

    2010-02-01

    Full Text Available Abstract Background The Botrytis cinerea xylanase Xyn11A has been previously shown to be required for full virulence of this organism despite its poor contribution to the secreted xylanase activity and the low xylan content of B. cinerea hosts. Intriguingly, xylanases from other fungi have been shown to have the property, independent of the xylan degrading activity, to induce necrosis when applied to plant tissues, so we decided to test the hypothesis that secreted Xyn11A contributes to virulence by promoting the necrosis of the plant tissue surrounding the infection, therefore facilitating the growth of this necrotroph. Results We show here that Xyn11A has necrotizing activity on plants and that this capacity is conserved in site-directed mutants of the protein lacking the catalytic activity. Besides, Xyn11A contributes to the infection process with the necrotizing and not with the xylan hydrolyzing activity, as the catalytically-impaired Xyn11A variants were able to complement the lower virulence of the xyn11A mutant. The necrotizing activity was mapped to a 30-amino acids peptide in the protein surface, and this region was also shown to mediate binding to tobacco spheroplasts by itself. Conclusions The main contribution of the xylanase Xyn11A to the infection process of B. cinerea is to induce necrosis of the infected plant tissue. A conserved 30-amino acids region on the enzyme surface, away from the xylanase active site, is responsible for this effect and mediates binding to plant cells.

  8. A Fusarium graminearum xylanase expressed during wheat infection is a necrotizing factor but is not essential for virulence.

    Science.gov (United States)

    Sella, Luca; Gazzetti, Katia; Faoro, Franco; Odorizzi, Silvana; D'Ovidio, Renato; Schäfer, Wilhelm; Favaron, Francesco

    2013-03-01

    Fusarium graminearum is the fungal pathogen mainly responsible for Fusarium head blight (FHB) of cereal crops, which attacks wheat spikes, reducing crop production and quality of grain by producing trichothecene mycotoxins. Several cytohistological studies showed that spike infection is associated with the production of cell wall degrading enzymes. Wheat tissue, as in other commelinoid monocot plants, is particularly rich in xylan which can be hydrolyzed by fungal endo-1,4-β-xylanase. The FG_03624 is one of the most expressed xylanase genes in wheat spikes 3 days after inoculation and was heterologously expressed in the yeast Pichia pastoris. The recombinant protein (22.7 kDa) possessed xylanase activity and induced cell death and hydrogen peroxide accumulation in wheat leaves infiltrated with 10 ng/μl or in wheat lemma surface treated with 20 ng/μl. This effect reflects that observed with other described fungal xylanases (from Trichoderma reesei, Trichoderma viride and Botrytis cinerea) with which the FG_03624 protein shares a stretch of amino acids reported as essential for elicitation of necrotic responses. Several F. graminearum mutants with the FG_03624 gene disrupted were obtained, and showed about 40% reduction of xylanase activity in comparison to the wild type when grown in culture with xylan as carbon source. However, they were fully virulent when assayed by single floret inoculation on wheat cvs. Bobwhite and Nandu. This is the first report of a xylanase able to induce hypersensitive-like symptoms on a monocot plant.

  9. Cloning, Expression, and Purification of Xylanase Gene from Bacillus licheniformis for Use in Saccharification of Plant Biomass.

    Science.gov (United States)

    Zafar, Asma; Aftab, Muhammad Nauman; Din, Zia Ud; Aftab, Saima; Iqbal, Irfana; Shahid, Anam; Tahir, Arifa; Haq, Ikram Ul

    2016-01-01

    The xylanase gene (xynA) of Bacillus licheniformis 9945A was cloned and expressed in Escherichia coli BL21(DE3) using pET-22b(+) as an expression vector. The recombinant xylanase enzyme was purified by ammonium sulfate precipitation, followed by single-step immobilized metal ion affinity chromatography with a 57.58-fold purification having 138.2 U/mg specific activity and recovery of 70.08 %. Molecular weight of the purified xylanase, 23 kDa, was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was stable for up to 70 °C with a broad pH range of 4-9 pH units. The enzyme activity was increased in the presence of metal ions especially Ca(+2) and decreased in the presence of EDTA, indicating that the xylanase was a metalloenzyme. However, an addition of 1-4 % Tween 80, β-mercaptoethanol, and DTT resulted in the increase of enzyme activity by 51, 52, and 5 %, respectively. Organic solvents with a concentration of 10-40 % slightly decreased the enzyme activity. The xylanase enzyme possesses the ability of bioconversion of plant biomasses like wheat straw, rice straw, and sugarcane bagasse. Among the different tested biomasses, the highest saccharification percentage was observed with 1 % sugarcane bagasse after 72 h of incubation at 50 °C with 20 units of enzyme. The results suggest that recombinant xylanase can be used in the bioconversion of natural biomasses into simple sugars which could be further used for the production of biofuel. PMID:26438315

  10. A proteomics-based study of endogenous and microbial xylanases and xylanase inhibitors associated with barley grains used for liquid feed

    DEFF Research Database (Denmark)

    Sultan, Abida

    The mature barley grain contains a complement of enzymes that are synthesized during seed development for degradation of seed storage reserves during germination. These enzyme activities (first wave enzymes) are considered important for maximizing nutrient digestibility in food and feed. Several...... approach was applied to profile and characterize the composition of the fungal community populating the surface of barley grains across different cultivars and their secretomes. It was revealed, the barley cultivars with high microbial xylanase activity levels were found to contain high numbers of storage...... strategies, such as liquid feed and supplementation of amino acids and microbial exogenous enzymes, are applied to improve protein absorption. A diverse commensal microbial community populates the cereal grains. The colonizing microflora constitute an integrated part of the seeds and interact...

  11. Kinetics and substrate selectivity of a Triticum aestivum xylanase inhibitor (TAXI) resistant D11F/R122D variant of Bacillus subtilis XynA xylanase

    DEFF Research Database (Denmark)

    Rasmussen, Louise Enggaard; Sørensen, Jens F.; Meyer, Anne S.

    2010-01-01

    ), water-unextractable arabinoxylan (WUAX), birchwood xylan, and wheat bran. Both the BsX and the BsX(mut) catalyzed the release of xylo-oligosaccharides with higher degree of polymerization from WUAX than from WEAX. At equimolar addition levels the activity of the BsX(mut) was lower than that of the Bs......X with respect to both the initial rate and the product yields obtained after prolonged reaction on the xylan substrates. The calculated substrate selectivity factors indicated that the BsX and the BsX(mut) both had higher catalytic rate on WUAX than on WEAX. Addition of a 100:1 (TAXI:xylanase) molar ratio...

  12. Characterization and comparison of Clostridium cellulovorans endoglucanases-xylanases EngB and EngD hyperexpressed in Escherichia coli.

    OpenAIRE

    Foong, F C; Doi, R H

    1992-01-01

    By the use of a T7 expression system, endoglucanases-xylanases EngB and EngD from Clostridium cellulovorans were hyperexpressed and purified from Escherichia coli. The two enzymes demonstrated both endoglucanase and xylanase activities. The substrate specificities of both endoglucanases were similar except that EngD had four-times-greater p-nitrophenyl beta-1,4-cellobiosidase activity. The two proteins were very homologous (80%) up to the Pro-Thr-Thr region which divided the protein into -NH2...

  13. Characterization of a purified thermostable xylanase from Caldicoprobacter algeriensis sp. nov. strain TH7C1(T)

    OpenAIRE

    Bouanane-Darenfed, A.; Boucherba, N.; Bouacem, K.; Gagaoua, M.; Joseph, M; Kebbouche-Gana, S.; Nateche, F.; Hacene, H.; Ollivier, Bernard; Cayol, J. L.; Fardeau, Marie-Laure

    2016-01-01

    The present study investigates the purification and biochemical characterization of an extracellular thermostable xylanase (called XYN35) from Caldicoprobacter algeriensis sp. nov., strain TH7C1(T), a thermophilic, anaerobic strain isolated from the hydrothermal hot spring of Guelma (Algeria). The maximum xylanase activity recorded after 24 h of incubation at 70 degrees C and in an optimized medium containing 10 g/L mix birchwood-and oats spelt-xylan was 250 U/mL. The pure protein was obtaine...

  14. One-step purification and characterization of cellulase-free xylanase produced by alkalophilic Bacillus subtilis ash

    OpenAIRE

    Sanghi, Ashwani; Garg, Neelam; Gupta, V. K.; Mittal, Ashwani; R.C. Kuhad

    2010-01-01

    The present study describes the one-step purification and characterization of an extracellular cellulase-free xylanase from a newly isolated alkalophilic and moderately thermophilic strain of Bacillus subtilis ASH. Xylanase was purified to homogeneity by 10.5-fold with ~43% recovery using ion-exchange chromatography through CM-Sephadex C-50. The purified enzyme revealed a single band on SDS-PAGE gel with a molecular mass of 23 kDa. It showed an optimum pH at 7.0 and was stable over the pH ran...

  15. Isothermal titration calorimetry and surface plasmon resonance allow quantifying substrate binding to different binding sites of Bacillus subtilis xylanase

    DEFF Research Database (Denmark)

    Cuyvers, Sven; Dornez, Emmie; Abou Hachem, Maher;

    2012-01-01

    Isothermal titration calorimetry and surface plasmon resonance were tested for their ability to study substrate binding to the active site (AS) and to the secondary binding site (SBS) of Bacillus subtilis xylanase A separately. To this end, three enzyme variants were compared. The first was a cat......Isothermal titration calorimetry and surface plasmon resonance were tested for their ability to study substrate binding to the active site (AS) and to the secondary binding site (SBS) of Bacillus subtilis xylanase A separately. To this end, three enzyme variants were compared. The first...

  16. ENHANCED PRODUCTION OF CELLULASE-FREE XYLANASE BY ALKALOPHILIC BACILLUS SUBTILIS ASH AND ITS APPLICATION IN BIOBLEACHING OF KRAFT PULP

    OpenAIRE

    Ashwani Sanghi; Neelam Garg; Kalika Kuhar; Kuhad, Ramesh C.; Gupta, Vijay K

    2009-01-01

    This paper reports high level production of a cellulase-free xylanase using wheat bran, a cost-effective substrate, under submerged fermentation by alkalophilic Bacillus subtilis ASH. Production of xylanase was observed even at alkaline pH up to 11.0 and temperature 60 °C, although the highest enzyme titer was recorded at neutral pH and 37 °C. The enzyme production under optimized fermentation was 1.5-fold greater than under unoptimized conditions. Pre-treatment of unbleached pulp of 10% cons...

  17. CLONING, PURIFICATION AND CHARACTERIZATION OF HALOTOLERANT XYLANASE FROM Geobacillus Thermodenitrificans C5

    Directory of Open Access Journals (Sweden)

    Muhammad Irfan

    2016-06-01

    Full Text Available High levels of extracellular xylanase activity (994.50 IU/ml produced by Geobacillus thermodenitrificans C5 originated gene was detected when it was expressed in E. coli BL21 host. Thermostable xylanase (GthC5Xyl was purified to homogeneity and showed a molecular mass of approximately 44 kDa according to SDS-PAGE. The specific activity of the purified GthC5Xyl was up to 1243.125IU/mg with a 9.89-fold purification. The activity of GthC5Xyl was stimulated by CoCl2, MnSO4, CuSO4, MnCl2 but was inhibited by FeSO4, Hg, CaSO4. GthC5Xyl showed resistant to SDS, Tween 20, Triton X-100, β- Mercaptoethanol, PMSF, DTT, NEM and DEPC, SDS, and EDTA. A greater affinity for oat spelt xylan was exhibited by GthC5Xyl with maximum enzymatic activity at 60°C and 6.0 pH. The activity portrayed by GthC5Xyl was found to be acellulytic with stability at high temperature (70°C-80°C and low pH (4.0 to 8.0. Xylobiose and xylopentose were the end products of proficient oat spelt xylanase hydrolysis by GthC5Xyl. High SDS resistance and broader stability of GthC5Xyl proves it to be worthy of impending application in numerous industrial processes especially textile, detergents and animal feed industry.

  18. Fungal cellulase/xylanase production and corresponding hydrolysis using pretreated corn stover as substrates.

    Science.gov (United States)

    Zhang, Liang; Wang, Xiaoqing; Ruan, Zhenhua; Liu, Ying; Niu, Xiaorui; Yue, Zhengbo; Li, Zhimin; Liao, Wei; Liu, Yan

    2014-01-01

    Three pretreated corn stover (ammonia fiber expansion, dilute acid, and dilute alkali) were used as carbon source to culture Trichoderma reesei Rut C-30 for cellulase and xylanase production. The results indicated that the cultures on ammonia fiber expansion and alkali pretreated corn stover had better enzyme production than the acid pretreated ones. The consequent enzymatic hydrolysis was performed applying fungal enzymes on pretreated corn stover samples. Tukey's statistical comparisons exhibited that there were significant differences on enzymatic hydrolysis among different combination of fungal enzymes and pretreated corn stover. The higher sugar yields were achieved by the enzymatic hydrolysis of dilute alkali pretreated corn stover.

  19. Purification and characterization of thermoalkalophilic xylanase isolated from the Enterobacter sp. MTCC 5112

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    main types of hemicelluloses are xylan and glucomannan [38]. Xylan has a complex structure consisting of ? -1,4 linked xylose residues in the backbone to which short side chains of o-acetyl, ? -L arabinofuranosyl, D- ? glucuronic and phenolic acid... for industrial applications then the enzyme need to be thermophilic and alkalophilic in nature. However, most of the xylanases known to date are optimally active at temperatures below 50 ?C and are active in acidic or neutral pH [37,30,39]. Conversely, only a...

  20. Application of xylanases from Amazon Forest fungal species in bleaching of eucalyptus kraft pulps

    Directory of Open Access Journals (Sweden)

    Roseli Garcia Medeiros

    2007-03-01

    Full Text Available Crude xylanase preparations from Penicillium corylophilum, Aspergillus niger and Trichoderma longibrachiatum were used to treat Eucalyptus kraft pulp, prior to chlorine dioxide and alkaline bleaching sequences. The enzyme pretreatment improved brightness and delignification of non-delignified and oxygen-bleached samples of eucalyptus kraft pulp. Xylanase preparations from T. longibrachiatum and P. corylophilum were more effective to reduce pulp kappa number. A small reduction in viscosity was obtained when the oxygen-bleached pulp was treated with xylanase preparation from A. niger. For all enzyme samples, the best release of chromophoric material from the pulp was at 237 nm. The enzyme preparation from P. corylophilum was responsible for the highest release of reducing sugar at a dosage interval of 10-20 IU/g dry weight pulp. Scanning electron microscopy studies of oxygen-bleached pulp after xylanase treatment revealed morphological changes, including holes, cracks, filament forming and peeling.Amostras de xilanases de extratos brutos de Penicillium corylophilum, Aspergillus niger e Trichoderma longibrachiatum foram utilizadas no branqueamento de polpa kraft de eucalipto antes das seqüências alcalina e dióxido de cloro. O pré-tratamento enzimático melhorou a alvura e o processo de deslignificação de amostras de polpa kraft de eucalipto não-tratada e tratada com oxigênio. Amostras de xilanases de T. longibrachiatum e P. corylophilum foram mais efetivas na redução do número kappa da polpa. A polpa tratada com oxigênio sofreu uma pequena redução na sua viscosidade quando incubada com amostra de xilanase de A. niger. Para todas as amostras de xilanases, a maior liberação de cromóforos da polpa foi a 237 nm. A amostra de xilanase de P. corylophilum liberou maior quantidade de açúcar redutor da polpa, utilizando dosagem de 10-20 UI/g de peso seco da polpa. Estudos de microscopia eletrônica de varredura revelaram várias altera

  1. Low-cost carbon sources for the production of a thermostable xylanase by Aspergillus niger

    OpenAIRE

    Ana Cláudia Elias Pião Benedetti; Eliana Dantas da Costa; Caio Casale Aragon; Andréa Francisco dos Santos; Antônio José Goulart; Derlene Attili-Angelis; Rubens Monti

    2013-01-01

    A strain of the filamentous fungus Aspergillus niger was isolated and shown to possess extracellular xylanolytic activity. These enzymes have biotechnological potential and can be employed in various industries. This fungus produced its highest xylanase activity in a medium made up of 0.1% CaCO3 , 0.5% NaCl, 0.1% NH4 Cl, 0.5% corn steep liquor and 1% carbon source, at pH 8.0. A lowcost hemicellulose residue (powdered corncob) proved to be an excellent inducer of the A. ni...

  2. Partial purification and characterization of Xylanase from Trichoderma viride produced under SSF

    OpenAIRE

    Irfan, M.; Q. Syed

    2012-01-01

    Summary: In the present study xylanase enzyme was produced from Trichoderma viride in solid state fermentation using sugarcane bagasse as a substrate. The whole fermentation process was carried out in 250ml Erlenmeyer flask at 30oC for seven days of fermentation period. The enzyme was partially purified by ammonium sulphate (60%) fractionation followed by dialysis. The partially purified enzyme was further characterized showing optimum pH and temperature of 5.0 and 50oC respectively. Metal pr...

  3. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw.

    Science.gov (United States)

    Li, Yanfei; Ge, Xiaoyan; Sun, Zongping; Zhang, Junhua

    2015-06-01

    The competitive adsorption between cellulases and additives on lignin in the hydrolysis of lignocelluloses has been confirmed, whereas the effect of additives on the interaction between xylanase and lignin is not clear. In this work, the effects of additives, poly(ethylene glycol) 2000, poly(ethylene glycol) 6000, Tween 20, and Tween 80, on the xylanase adsorption/desorption onto/from acid-insoluble lignin from corn stover (CS-lignin) and wheat straw (WS-lignin) were investigated. The results indicated that the additives could adsorb onto isolated lignin and reduce the xylanase adsorption onto lignin. Compared to CS-lignin, more additives could adsorb onto WS-lignin, making less xylanase adsorbed onto WS-lignin. In addition, the additives could enhance desorption of xylanase from lignin, which might be due to the competitive adsorption between xylanase and additives on lignin. The released xylanase from lignin still exhibited hydrolytic capacity in the hydrolysis of isolated xylan and xylan in corn stover.

  4. Structural Analysis of Xylanase from Marine Thermophilic Geobacillus stearothermophilus in Tanjung Api, Poso, Indonesia

    Directory of Open Access Journals (Sweden)

    BUDI SAKSONO

    2010-12-01

    Full Text Available A xylanase gene, xynA, has been cloned from thermophilic strain Geobacillus stearothermophilus, which was isolated from marine Tanjung Api, Indonesia. The polymerase chain reaction product of 1266 bp of xynA gene consisted of 1221 bp open reading frame and encoded 407 amino acids including 30 residues of signal peptide. The sequence exhibited highest identity of 98.7% in the level of amino acid, with an extracellular endo-1,4-β-xylanase from G. stearothermophilus T-6 (E-GSX T-6 of the glycoside hydrolase family 10 (GH10. A comparative study between the local strain G. stearothermophilus (GSX L and E-GSX T-6 on homology of amino acid sequence indicated five differents amino acids in the gene. They were Threonine/Alanine (T/A, Asparagine/Aspartate (N/D, Lysine/Asparagine (K/N, Isoleucine/Methionine (I/M, Serine/Threonine (S/T at the position 220, 227, 228, 233, and 245, respectively. Protein structural analysis of those differences suggested that those amino acids may play role in biochemical properties such as enzyme stability, in particular its thermostability.

  5. Contribution of ethanol-tolerant xylanase G2 from Aspergillus oryzae on Japanese sake brewing.

    Science.gov (United States)

    Sato, Yuichiro; Fukuda, Hisashi; Zhou, Yan; Mikami, Shigeaki

    2010-12-01

    We purified three xylanase isozymes (XynF1, XynF3 and XynG2) from a solid-state Aspergillus oryzae RIB128 culture using chromatography. The results of our sake-brewing experiment, in which we used exogenously supplemented enzymes, revealed that only XynG2 improved the alcohol yield and the material utilization. The alcohol yield of the XynG2 batch displayed an increase of 4.4% in comparison to the control, and the amount of sake cake decreased by 4.6%. The contribution of XynG2 was further confirmed through our brewing experiment in which we used the yeast heterogeneously expressing fungal xylanase isozymes. Interestingly XynG1, an enzyme with a XynG2-like sequence that is more vulnerable to ethanol, did not improve the sake-mash fermentation. The stability of XynG2 in ethanol was prominent, and it retained most of its original activity after we exposed it to 80% ethanol for 30min, whereas the stability of the other isozymes in ethanol, including XynG1, was much lower (20-25% ethanol). We concluded, therefore, that the improvement of material utilization achieved with XynG2 is primarily attributable to its characteristically high stability in ethanol, thereby, effectively degrading rice endosperm cell walls under high-alcohol conditions such as a sake-mash environment. PMID:20727822

  6. Cellulase and Xylanase Production by Penicillium echinulatum in Submerged Media Containing Cellulose Amended with Sorbitol

    Directory of Open Access Journals (Sweden)

    Carla Eliana Todero Ritter

    2013-01-01

    Full Text Available The present work investigated the use of sorbitol as a soluble carbon source, in association with cellulose, to produce cellulases and xylanases in submerged cultures of Penicillium echinulatum 9A02S1. Because cellulose is an insoluble carbon source, in cellulase production, there are some problems with rheology and oxygen transfer. The submerged fermentations containing media composed of 0, 0.25, 0.5, 0.75, and 1% (w/v sorbitol and cellulose that were added at different times during the cultivation; 0.2% (w/v soy bran; 0.1% (w/v wheat bran; and a solution of salts. The highest filter paper activity (FPA ( IU·mL−1 was obtained on the seventh day in the medium containing 0.5% (w/v sorbitol and 0.5% (w/v cellulose added 24 h after the start of cultivation. However, the CMCases showed an activity peak on the sixth day ( IU·mL−1 in the medium containing 0.75% (w/v sorbitol and 0.75% (w/v cellulose added after 12 h of cultivation. The xylanases showed the highest activity in the medium with 0.75% (w/v sorbitol and 0.25% (w/v cellulose added 36 h after the start of cultivation. This strategy enables the reduction of the cellulose concentration, which in high concentrations can cause rheological and oxygen transfer problems.

  7. Purification and characterization of the xylanase produced by Jonesia denitrificans BN-13.

    Science.gov (United States)

    Boucherba, Nawel; Gagaoua, Mohammed; Copinet, Estelle; Bettache, Azeddine; Duchiron, Francis; Benallaoua, Said

    2014-03-01

    Jonesia denitrificans BN-13 produces six xylanases: Xyl1, Xyl2, Xyl3, Xyl4, Xyl5, and Xyl6; the Xyl4 was purified and characterized after two consecutive purification steps using ultrafiltration and anion exchange chromatography. The xylanase-specific activity was found to be 77 unit (U)/mg. The molecular weight of the Xyl4 estimated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed a monomeric isoenzyme of about 42 kDa. It showed an optimum pH value of 7.0 and a temperature of 50 °C. It was stable at 50 °C for 9.34 h. The enzyme showed to be activated by Mn(+2), β-mercaptoethanol, and dithiothreitol (DTT) with a high affinity towards birchwood xylan (with a K(m) of 1 mg ml(-1)) and hydrolysis of oat-spelt xylan with a K(m) of 1.85 mg ml(-1). The ability of binding to cellulose and/or xylan was also investigated. PMID:24425300

  8. Endo-xylanase and endo-cellulase-assisted extraction of pectin from apple pomace.

    Science.gov (United States)

    Wikiera, Agnieszka; Mika, Magdalena; Starzyńska-Janiszewska, Anna; Stodolak, Bożena

    2016-05-20

    Pectins were extracted from apple pomace with monoactive preparation of endo-xylanase and endo-cellulase. The process was conducted for 10 h in conditions of pH 5.0 at 40 °C, with constant shaking. Endo-xylanase application resulted in the highest extraction efficiency of pectins (19.8%). The obtained polymer was characterised by a very high molecular mass, high level of neutral sugars - mainly arabinose, galactose and glucose, and very high DM (73.4). It also contained the highest level of protein and phenols. Pectin extracted with endo-cellulase had 1.5 fold lower molecular mass but contained significantly more GalA (70.5%) of a high degree of methylation (66.3%). The simultaneous application of both enzymatic preparations resulted in their cooperation, leading to a decrease of both the extraction efficiency and the molecular mass of pectin. However, this pectin was distinguished by the highest GalA (74.7%) and rhamnose contents.

  9. Cellulase and xylanase activity during the decomposition of three aquatic macrophytes in a tropical oxbow lagoon.

    Science.gov (United States)

    Sciessere, L; Cunha-Santino, M B; Bianchini, I

    2011-07-01

    Due to the connection between enzymatic activity and degradation of different fractions of organic matter, enzyme assays can be used to estimate degradation rates of particulate and dissolved organic carbon in freshwater systems. The aim of this study was to quantify and model the enzymatic degradation involving the decomposition of macrophytes, describing temporal activity of cellulases (EC 3.2.1.4 and EC 3.2.1.91) and xylanase (EC 3.2.1.8) during in situ decomposition of three aquatic macrophytes (Salvinia sp., Eichhornia azurea and Cyperus giganteus) on the surface and water-sediment interface (w-s interface) of an oxbow lagoon (Óleo lagoon) within a natural Brazilian Savanna Reserve. Overall, the enzymatic degradation of aquatic macrophytes in Óleo lagoon occurred during the whole year and was initiated together with leaching. Xylanase production was ca. 5 times higher than cellulase values due to easy access to this compound by cellulolytic microorganisms. Enzymatic production and detritus mass decay were similar on the surface and w-s interface. Salvinia sp. was the most recalcitrant detritus, with low mass decay and enzymatic activity. E. azurea and C. giganteus decomposition rates and enzymatic production were high and similar. Due to the physicochemical homogeneity observed in the Óleo lagoon, the differences between the decay rates of each species are mostly related with detritus chemical quality. PMID:24031706

  10. Improvement of thermostability and activity of Trichoderma reesei endo-xylanase Xyn III on insoluble substrates.

    Science.gov (United States)

    Matsuzawa, Tomohiko; Kaneko, Satoshi; Yaoi, Katsuro

    2016-09-01

    Trichoderma reesei Xyn III, an endo-β-1,4-xylanase belonging to glycoside hydrolase family 10 (GH10), is vital for the saccharification of xylans in plant biomass. However, its enzymatic thermostability and hydrolytic activity on insoluble substrates are low. To overcome these difficulties, the thermostability of Xyn III was improved using random mutagenesis and directed evolution, and its hydrolytic activity on insoluble substrates was improved by creating a chimeric protein. In the screening of thermostable Xyn III mutants from a random mutagenesis library, we identified two amino acid residues, Gln286 and Asn340, which are important for the thermostability of Xyn III. The Xyn III Gln286Ala/Asn340Tyr mutant showed xylanase activity even after heat treatment at 60 °C for 30 min or 50 °C for 96 h, indicating a dramatic enhancement in thermostability. In addition, we found that the addition of a xylan-binding domain (XBD) to the C-terminal of Xyn III improved its hydrolytic activity on insoluble xylan. PMID:27138202

  11. Xylanase Activity of Streptomyces violascences BF 3.10 on Xylan Corncobs and its Xylooligosaccharide Production

    Directory of Open Access Journals (Sweden)

    W. Salupi

    2015-04-01

    Full Text Available Corn is one of the important carbohydrate sources in Indonesia that is mainly used for food and industrial materials. In addition, the byproducts of corn, such as corncobs, have been reported as xylan-containing materials that can be utilized as substrate in xylooligosaccharides (XOS production. XOS are natural prebiotic fibers that can enhance the performance of animal’s digestive system. The main objective of this study was to exploit xylan from corncobs to produce XOS. The research consisted of extraction and production of xylan from corncobs and the synthesis of XOS from corncob-produced xylan. The corncob and Streptomyces violascens BF 3.10 xylanase is a collection of PPSHB IPB Laboratory. Corncobs xylan extracted by using alkaline method and reducting sugar was analyzed by dinitrosalicylic acid method. The xylan extraction from corncobs could produce 7.93% (w/w of xylan. The activity of S. violascens BF 3.10 xylanase on the substrate of concorb-produced xylan was 6.4 U/mL at the optimum temperature of 60 °C in 50 mM phosphate buffer with pH 5.5. The thin layer chromatography analysis indicated that 1% (w/v corn-cob xylan could produce XOS with degree of polymerization (DP 3.92. XOS, with DP ranging from 2-4, could be used as a livestock feed mixture to stimulate the growth of normal microbes in the gastrointestinal tract of livestock.

  12. Fusion of carbohydrate binding modules from Thermotoga neapolitana with a family 10 xylanase from Bacillus halodurans S7.

    Science.gov (United States)

    Mamo, Gashaw; Hatti-Kaul, Rajni; Mattiasson, Bo

    2007-01-01

    Xylanase A of Thermotoga neapolitana contains binding domains both at the N- and C-terminal ends of the catalytic domain. In the N-terminal position it contains two carbohydrate-binding modules (CBM) which belong to family 22. These CBMs bind xylan but not to cellulose. The gene encoding the mature peptide of these CBMs was fused with an alkaline active GH10 xylanase from Bacillus halodurans S7 and expressed in Escherichia coli. The (His)(6) tagged hybrid protein was purified by immobilized metal affinity chromatography and characterized. Xylan binding by the chimeric protein was influenced by NaCl concentration and pH of the binding medium. Binding increased with increasing salt concentration up to 200 mM. Higher extent of binding was observed under acidic conditions. The fusion of the CBM structures enhanced the hydrolytic efficiency of the xylanase against insoluble xylan, but decreased the stability of the enzyme. The optimum temperature and pH for the activity of the xylanase did not change.

  13. Engineering increased thermostability in the GH-10 endo-1,4-ß-xylanase from Thermoascus aurantiacus CBMAI 756

    Science.gov (United States)

    The GH10 endo-xylanase from Thermoascus aurantiacus CBMAI 756 (XynA) is industrially attractive due to its considerable thermostability and high specific activity. Considering the possibility of a further improvement in thermostability, eleven mutants were created in the present study via site-direc...

  14. Crystallization and preliminary crystallographic analysis of endo-1,4-beta-xylanase I from Aspergillus niger

    NARCIS (Netherlands)

    Krengel, U; Rozeboom, HJ; Kalk, KH; Dijkstra, BW

    1996-01-01

    A family G xylanase from Aspergillus niger has been crystallized using the vapor-diffusion method. Several crystal forms could be obtained using various sodium salts as precipitants. Three of the crystal forms belong to space groups P2(1), P2(1)2(1)2(1) and P4(3) and have cell parameters of approxim

  15. Constitutive expression of the xylanase inhibitor TAXI-III delays Fusarium head blight symptoms in durum wheat transgenic plants.

    Science.gov (United States)

    Moscetti, Ilaria; Tundo, Silvio; Janni, Michela; Sella, Luca; Gazzetti, Katia; Tauzin, Alexandra; Giardina, Thierry; Masci, Stefania; Favaron, Francesco; D'Ovidio, Renato

    2013-12-01

    Cereals contain xylanase inhibitor (XI) proteins which inhibit microbial xylanases and are considered part of the defense mechanisms to counteract microbial pathogens. Nevertheless, in planta evidence for this role has not been reported yet. Therefore, we produced a number of transgenic plants constitutively overexpressing TAXI-III, a member of the TAXI type XI that is induced by pathogen infection. Results showed that TAXI-III endows the transgenic wheat with new inhibition capacities. We also showed that TAXI-III is correctly secreted into the apoplast and possesses the expected inhibition parameters against microbial xylanases. The new inhibition properties of the transgenic plants correlate with a significant delay of Fusarium head blight disease symptoms caused by Fusarium graminearum but do not significantly influence leaf spot symptoms caused by Bipolaris sorokiniana. We showed that this contrasting result can be due to the different capacity of TAXI-III to inhibit the xylanase activity of these two fungal pathogens. These results provide, for the first time, clear evidence in planta that XI are involved in plant defense against fungal pathogens and show the potential to manipulate TAXI-III accumulation to improve wheat resistance against F. graminearum.

  16. Production and purification of an Endo-1,4-b-Xylanase from Humicola grisea var. thermoidea by electroelution

    OpenAIRE

    Monti Rubens; Cardello Leonardo; Custódio Marcos F.; Goulart Antonio J.; Sayama Adriana H.; Contiero Jonas

    2003-01-01

    Humicola grisea var. thermoidea produces two forms of extracellular xylanase. The component form 1 was purified using the electroelution method, due to the very small production of this extracellular enzyme. The apparent molecular mass was 61.8 kDa by SDS-PAGE.

  17. Isolation, Purification, and Characterization of Xylanase Produced by a New Species of Bacillus in Solid State Fermentation

    Directory of Open Access Journals (Sweden)

    Rajashri D. Kamble

    2012-01-01

    Full Text Available A thermoalkalophilic new species of Bacillus, similar to Bacillus arseniciselenatis DSM 15340, produced extracellular xylanase under solid state fermentation when wheat bran is used as carbon source. The extracellular xylanase was isolated by ammonium sulfate (80% precipitation and purified using ion exchange chromatography. The molecular weight of xylanase was ~29.8 ;kDa. The optimum temperature and pH for the enzyme activity were 50°C and pH 8.0. The enzyme was active on birchwood xylan and little active on p-nitrophenyl xylopyranoside but not on Avicel, CMC, cellobiose, and starch, showing its absolute substrate specificity. For birchwood xylan, the enzyme gave a Km 5.26 ;mg/mL and Vmax 277.7 ;μmol/min/mg, respectively. In addition, the xylanase was also capable of producing high-quality xylo-oligosaccharides, which indicated its application potential not only in pulp biobleaching processes but also in the nutraceutical industry.

  18. ENHANCED PRODUCTION OF CELLULASE-FREE XYLANASE BY ALKALOPHILIC BACILLUS SUBTILIS ASH AND ITS APPLICATION IN BIOBLEACHING OF KRAFT PULP

    Directory of Open Access Journals (Sweden)

    Ashwani Sanghi

    2009-08-01

    Full Text Available This paper reports high level production of a cellulase-free xylanase using wheat bran, a cost-effective substrate, under submerged fermentation by alkalophilic Bacillus subtilis ASH. Production of xylanase was observed even at alkaline pH up to 11.0 and temperature 60 °C, although the highest enzyme titer was recorded at neutral pH and 37 °C. The enzyme production under optimized fermentation was 1.5-fold greater than under unoptimized conditions. Pre-treatment of unbleached pulp of 10% consistency with crude xylanase (6 IU/g o.d. pulp at 60 ºC for 2 h increased the final brightness by 4.9%. The enzyme treatment reduced the chlorine consumption by 28.6% with the same brightness as in the control. A reduction in kappa number and increase in viscosity was observed after enzyme pre-treatment. Scanning electron microscopy revealed loosening and swelling of pulp fibers. The strength properties viz. grammage, fiber thickness, beating degree, tensile index, breaking length, tear index and double fold of the treated pulp were improved as compared to the control pulp. This study reveals the potential of B. subtilis ASH xylanase as a biobleaching agent for the paper and pulp industry.

  19. Cloning and in-silico analysis of beta-1,3-xylanase from psychrophilic yeast, Glaciozyma antarctica PI12

    Science.gov (United States)

    Nor, Nooraisyah Mohamad; Bakar, Farah Diba Abu; Mahadi, Nor Muhammad; Murad, Abdul Munir Abdul

    2015-09-01

    A beta-1,3-xylanase (EC 3.2.1.32) gene from psychrophilic yeast, Glaciozyma antarctica has been identified via genome data mining. The enzyme was grouped into GH26 family based on Carbohydrate Active Enzyme (CaZY) database. The molecular weight of this protein was predicted to be 42 kDa and is expected to be soluble for expression. The presence of signal peptide suggested that this enzyme may be released extracellularly into the marine environment of the host's habitat. This supports the theory that such enzymatic activity is required for degradation of nutrients of polysaccharide origins into simpler carbohydrates outside the environment before it could be taken up inside the cell. The sequence for this protein showed very little conservation (< 30%) with other beta-1,3-xylanases from available databases. Based on the phylogenetic analysis, this protein also showed distant relationship to other xylanases from eukaryotic origin. The protein may have undergone major substitution in its gene sequence order to adapt to the cold climate. This is the first report of beta-1,3-xylanase gene isolated from a psychrophilic yeast.

  20. Energy and nutrient utilization of broiler chickens fed corn-soybean meal and corn-based diets supplemented with xylanase.

    Science.gov (United States)

    Stefanello, C; Vieira, S L; Carvalho, P S; Sorbara, J O B; Cowieson, A J

    2016-08-01

    A study was conducted to evaluate the effects of increased levels of a β-xylanase on energy and nutrient utilization of broiler chickens fed corn-soy diets. A total of 480 slow feathering Cobb × Cobb 500 male broilers were randomly distributed to 10 treatments having 8 replicates of 6 birds each. Birds were fed a common starter diet to d 14 post hatch (3,050 kcal/kg AMEn, 21.7% CP, 1.05% Ca, and 0.53% nPP). The experimental diets were provided afterwards until 25 d. Two experimental diets, a conventional corn/soy-based basal diet (CS) and the basal diet in which 40% of the diet was displaced by corn (CN), were fed as-is or supplemented with 50, 100, 150, or 200 fungal β-xylanase units (FXU)/kg. Dietary treatments were distributed factorially as a 2 × 5 arrangement. Samples of feed, excreta, and ileal digesta were analyzed for determination of ileal digestible energy (IDE), metabolizable energy, and total tract retention of protein and lipid. No interactions between diet and xylanase were observed. The CS diets had higher (P energy utilization and nutrient digestibility when compared to the CN diets. AMEn and IDE were improved (P energy utilization and digestibility of crude protein and dry matter increased with xylanase supplementation in corn/soy-based diets. When xylanase was tested in the CS diet, 92 and 124 FXU/kg maximized the energy release effect; however, the maximum energy response in the CN diet or corn was not achieved until 200 FXU/kg.

  1. Utilization of Agro-industrial Wastes for the Simultaneous Production of Amylase and Xylanase by Thermophilic Actinomycetes

    Directory of Open Access Journals (Sweden)

    Renu Singh

    2012-12-01

    Full Text Available Agro-industrial wastes such as sugarcane bagasse, wheat bran, rice bran, corn cob and wheat straw are cheapest and abundantly available natural carbon sources. The present study was aimed to production of amylase and xylanase simultaneously using agro-industrial waste as the sole carbon source. Seven thermophilic strains of actinomycete were isolated from the mushroom compost. Among of these, strain designated MSC702 having high potential to utilize agro-industrial wastes for the production of amylase and xylanase. Strain MSC702 was identified as novel species of Streptomyces through morphological characterization and 16S rRNA gene sequence. Enzyme production was determined using 1% (w/v of various agro-industrial waste in production medium containing (g/100mL: K2HPO4(0.1, (NH42SO4(0.1, NaCl (0.1, MgSO4(0.1 at pH 7.0 after incubation of 48 h at 50°C. The amylase activity (373.89 IU/mL and xylanase activity (30.15 IU/mL was maximum in rice bran. The decreasing order of amylase and xylanase activity in different type of agro-industrial wastes were found rice bran (RB > corn cob (CC > wheat bran (WB > wheat straw (WS > sugarcane bagasse (SB and rice bran (RB > wheat bran (WB > wheat straw (WS > sugarcane bagasse (SB > corn cob (CC, respectively. Mixed effect of different agro-industrial wastes was examined in different ratios. Enzyme yield of amylase and xylanase was ~1.3 and ~2.0 fold higher with RB: WB in 1:2 ratio.

  2. GH10 xylanase D from Penicillium funiculosum: biochemical studies and xylooligosaccharide production

    Directory of Open Access Journals (Sweden)

    Giardina Thierry

    2011-04-01

    Full Text Available Abstract Background The filamentous fungus Penicillium funiculosum produces a range of glycoside hydrolases (GH. The XynD gene, encoding the sole P. funiculosum GH10 xylanase described so far, was cloned into the pPICZαA vector and expressed in methylotrophe yeast Pichia pastoris, in order to compare the results obtained with the P. funiculosum GH11 xylanases data. Results High level expression of recombinant XynD was obtained with a secretion of around 60 mg.L-1. The protein was purified to homogeneity using one purification step. The apparent size on SDS-PAGE was around 64 kDa and was 46 kDa by mass spectrometry thus higher than the expected molecular mass of 41 kDa. The recombinant protein was N- and O-glycosylated, as demonstrated using glycoprotein staining and deglycosylation reactions, which explained the discrepancy in molecular mass. Enzyme-catalysed hydrolysis of low viscosity arabinoxylan (LVAX was maximal at pH 5.0 with Km(app and kcat/Km(app of 3.7 ± 0.2 (mg.mL-1 and 132 (s-1mg-1.mL, respectively. The activity of XynD was optimal at 80°C and the recombinant enzyme has shown an interesting high thermal stability at 70°C for at least 180 min without loss of activity. The enzyme had an endo-mode of action on xylan forming mainly xylobiose and short-chain xylooligosaccharides (XOS. The initial rate data from the hydrolysis of short XOS indicated that the catalytic efficiency increased slightly with increasing their chain length with a small difference of the XynD catalytic efficiency against the different XOS. Conclusion Because of its attractive properties XynD might be considered for biotechnological applications. Moreover, XOS hydrolysis suggested that XynD possess four catalytic subsites with a high energy of interaction with the substrate and a fifth subsite with a small energy of interaction, according to the GH10 xylanase literature data.

  3. 嗜热多拟青霉发酵产物杀虫活性的初步研究%Preliminary Study on Insecticidal Activity of Zymotic Metabolites from Polypaecilum thermophilum D.M.Wang et D.C.Li

    Institute of Scientific and Technical Information of China (English)

    王冬梅

    2011-01-01

    以纯化的嗜热多拟青霉液体发酵培养,测定其代谢产物对棉蚜和温室白粉虱的毒杀效果.用水培棉苗法培养棉蚜,盆栽番茄培养温室白粉虱,采用菌株发酵产物浸渍法进行生物测定.结果表明:该代谢产物表现出较高的毒杀作用,室内生物测定72 h对棉蚜和温室白粉虱的校正死亡率分别为80.5%和66.3%.%The purifided Polypaecilum thermophilum D. M. Wang et D. C. Li was cultured by fermenta tion , and the effects of its zymotic metabolites on Aphis gossypii raised on water - planting cotton seedlings and Trialeurodes vaporariorum raised on potted tomato plants were studied. The bioassay was conducted through dipping leaves in fungi zymotic metabolites. The results showed that the zymotic metabolites had higher toxicity to Aphis gossypii and Trialeurodes vaporariorum with adjusted mortality of 80.5% and 66.3% respectively after bioassay for 72 hours.

  4. Optimization of Xylanase Production through Response Surface Methodology by Fusarium sp. BVKT R2 Isolated from Forest Soil and Its Application in Saccharification

    Science.gov (United States)

    Ramanjaneyulu, Golla; Rajasekhar Reddy, Bontha

    2016-01-01

    Xylanses are hydrolytic enzymes with wide applications in several industries like biofuels, paper and pulp, deinking, food, and feed. The present study was aimed at hitting at high yield xylanase producing fungi from natural resources. Two highest xylanase producing fungal isolates—Q12 and L1 were picked from collection of 450 fungal cultures for the utilization of xylan. These fungal isolates—Q12 and L1 were identified basing on ITS gene sequencing analysis as Fusarium sp. BVKT R2 (KT119615) and Fusarium strain BRR R6 (KT119619), respectively with construction of phylogenetic trees. Fusarium sp. BVKT R2 was further optimized for maximum xylanase production and the interaction effects between variables on production of xylanase were studied through response surface methodology. The optimal conditions for maximal production of xylanase were sorbitol 1.5%, yeast extract 1.5%, pH of 5.0, Temperature of 32.5°C, and agitation of 175 rpm. Under optimal conditions, the yields of xylanase production by Fusarium sp. BVKT R2 was as high as 4560 U/ml in SmF. Incubation of different lignocellulosic biomasses with crude enzyme of Fusarium sp. BVKT R2 at 37°C for 72 h could achieve about 45% saccharification. The results suggest that Fusarium sp. BVKT R2 has potential applications in saccharification process of biomass. PMID:27713726

  5. Production of xylooligosaccharides in SSF by Bacillus subtilis KCX006 producing β-xylosidase-free endo-xylanase and multiple xylan debranching enzymes.

    Science.gov (United States)

    Reddy, Shyam Sunder; Krishnan, Chandraraj

    2016-01-01

    Xylanase and xylooligosaccharides (XOS) are employed in food and feed industries. Though xylanase production from lignocellulosic materials (LCMs) by solid-state fermentation (SSF) is well known, the XOS formed during growth is not recovered due to its conversion to xylose by β-xylosidase and subsequent bacterial metabolism. A new strain, Bacillus subtilis KCX006, was exceptionally found to synthesize β-xylosidase-free endo-xylanase and multiple xylan debranching enzymes constitutively in the presence of LCMs. Absence of β-xylosidase resulted in accumulation of XOS during growth of KCX006 on LCMs. Therefore, this strain was used for simultaneous production of xylanase and XOS from agro-residues in solid-state fermentation (SSF). Partial purification of XOS from culture supernatant using activated charcoal followed by high-performance liquid chromatography (HPLC) analysis showed xylobiose to xylotetraose formed as the major products. Among various LCM substrates, wheat bran and groundnut oil-cake supported highest xylanase and XOS production at 2158 IU/gdw and 24.92 mg/gdw, respectively. The levels of xylanase and XOS were improved by 1.5-fold (3102 IU/gdw) and 1.9-fold (48 mg/gdw), respectively, by optimization of culture conditions. PMID:25310011

  6. Suitable conditions for xylanases activities from Bacillus sp. GA2(1 and Bacillus sp. GA1(6 and their properties for agricultural residues hydrolysis

    Directory of Open Access Journals (Sweden)

    Sudathip Chantorn

    2016-04-01

    Full Text Available Bacillus sp. GA2(1 and Bacillus sp. GA1(6 were isolated from soybean field in Khon Kaen province, Thailand. Crude enzymes from both isolates showed the activities of cellulase, xylanase, and mannanase at 37°C for 24 h. The highest xylanase activities of Bacillus sp. GA2(1 and Bacillus sp. GA1(6 were 1.58±0.25 and 0.82±0.16 U/ml, respectively. The relative xylanase activities from both strains were more than 60% at pH 5.0 to 8.0. The optimum temperature of xylanases was 50°C in both strains. The residual xylanase activities from both strains were more than 70% at 60°C for 60 min. Five agricultural wastes (AWs, namely coffee residue, soybean meal, potato peel, sugarcane bagasse, and corn cobs, were used as substrates for hydrolysis properties. The highest reducing sugar content of 101±1.32 µg/ml was obtained from soybean meal hydrolysate produced by Bacillus sp. GA2(1 xylanase.

  7. Inexpensive, rapid procedure for bulk purification of cellulase-free. beta. -1,4-D-xylanase of high specific activity

    Energy Technology Data Exchange (ETDEWEB)

    Tan, L.U.L.; Yu, E.K.C.; Louis-Seize, G.W.; Saddler, J.N.

    1987-01-01

    A process has been developed for the bulk purification of cellulase-free ..beta..-14-D-xylanase from the fungus Tirchoderma harzianum E58. The process involved the primary step of ultrafiltering the culture filtrate via a 10,000-molecular-weight cut-off membrane to separate the cellulase (retentate) and xylanase (permeate) fractions. The cellulase component was concentrated by 40- to 60-fold, resulting in an enzyme complex that could effectively hydrolyze high concentrations of cellulose and xylan to glucose and xylose. The xylanase was concentrated and solvent exchanged by adsorption to a cationic exchanger, SP-ZetaPrep 250, followed by elution with a pH change in the buffer to give a purified and concentrated xylanase complex dissolved in a low-salt buffer. The resultant xylanase system was pure by the criteria of sodium dodecyl sulfate polyacrylamide electrophoresis, had a very high specific activity of 2400 IU/mg protein, was virtually free of filter paper activity, and had a ratio of contaminating filter paper activity of 2 x 10/sup -6/. Approximately 3.3 g protein, which contained in excess of 7 x 10/sup 6/ IU xylanase activity was obtained from 17 L original culture filtrate. The process scheme was designed to facilitate scale-up to an industrial level of production.

  8. Solid-state Fermentation of Xylanase from Penicillium canescens 10-10c in a Multi-layer-packed Bed Reactor

    Science.gov (United States)

    Assamoi, Antoine A.; Destain, Jacqueline; Delvigne, Frank; Lognay, Georges; Thonart, Philippe

    Xylanase is produced by Penicillium canescens 10-10c from soya oil cake in static conditions using solid-state fermentation. The impact of several parameters such as the nature and the size of inoculum, bed-loading, and aeration is evaluated during the fermentation process. Mycelial inoculum gives more production than conidial inoculum. Increasing the quantity of inoculum enhances slightly xylanase production. Forced aeration induces more sporulation of strain and reduces xylanase production. However, forced moistened air improves the production compared to production obtained with forced dry air. In addition, increasing bed-loading reduces the specific xylanase production likely due to the incapacity of the Penicillium strain to grow deeply in the fermented soya oil cake mass. Thus, the best cultivation conditions involve mycelial inoculum form, a bed loading of 1-cm height and passive aeration. The maximum xylanase activity is obtained after 7 days of fermentation and attains 10,200 U/g of soya oil cake. These levels are higher than those presented in the literature and, therefore, show all the potentialities of this stock and this technique for the production of xylanase.

  9. Effect of penicillium mutation by UV and gamma radiation on xylanase production

    International Nuclear Information System (INIS)

    Many microorganisms produce enzymes which have importance in industrial processes. Usually this production, is not sufficient for these needs at economical level. The bioindustry concentrates on increasing the production of these enzymes. This leads to the progress of this kind of industry, which use different biotechnology means, for example mutation and screening to choice more potent strain. In this study Ultra Violet and Gamma irradiation conducted on Penicillium canescen in order to produce new mutant strains, have the ability to produce more xylanase enzyme for industrial uses. Ultra Violet irradiation enable to select five mutant strains having more enzyme production ability. The best mutant strain PCUV12 (159 unit/ml) was 40% higher than the mother strain, at the dose 150.72 j/cm2. Gamma radiation produced new mutant strain PCGR6 which produced 26% more enzyme than the mother strain at dose 250 Gy.(author)

  10. On the sensitivity of protein data bank normal mode analysis: an application to GH10 xylanases

    Science.gov (United States)

    Tirion, Monique M.

    2015-12-01

    Protein data bank entries obtain distinct, reproducible flexibility characteristics determined by normal mode analyses of their three dimensional coordinate files. We study the effectiveness and sensitivity of this technique by analyzing the results on one class of glycosidases: family 10 xylanases. A conserved tryptophan that appears to affect access to the active site can be in one of two conformations according to x-ray crystallographic electron density data. The two alternate orientations of this active site tryptophan lead to distinct flexibility spectra, with one orientation thwarting the oscillations seen in the other. The particular orientation of this sidechain furthermore affects the appearance of the motility of a distant, C terminal region we term the mallet. The mallet region is known to separate members of this family of enzymes into two classes.

  11. Production of xylooligosaccharides from forest waste by membrane separation and Paenibacillus xylanase hydrolysis

    Directory of Open Access Journals (Sweden)

    Chun-Han Ko

    2013-02-01

    Full Text Available Xylooligosaccharides (XO, derived from the alkaline (NaOH extractant of Mikania micrantha, were produced using multiple staged membrane separation and enzymatic xylanolysis. Staged nanofiltration (NMX, ultrafiltration (EUMX, and centrifugation (EMX processes for the ethanol precipitates were conducted. NMX recovered 97.26% of total xylose and removed 73.18% of sodium ions. Concentrations of total xylose were raised from 10.98 to 51.85 mg/mL by the NMX process. Recovered xylan-containing solids were hydrolyzed by the recombinant Paenibacillus xylanase. 68% XO conversions from total xylose of NMX was achieved in 24 hours. Xylopentaose (DP 5 was the major product from NMX and EMX hydrolysis. Xylohexaose (DP 6 was the major product from EUMX hydrolysis. Results of the present study suggest the applicability for XO production by nanofiltration, as NMX gave higher XO yields compared to those from a conventional ethanol-related lignocellulosic waste conversion process.

  12. Cellulase and Xylanase Production by Penicillium echinulatum in Submerged Media Containing Cellulose Amended with Sorbitol.

    Science.gov (United States)

    Todero Ritter, Carla Eliana; Camassola, Marli; Zampieri, Denise; Silveira, Mauricio Moura; Dillon, Aldo José Pinheiro

    2013-01-01

    The present work investigated the use of sorbitol as a soluble carbon source, in association with cellulose, to produce cellulases and xylanases in submerged cultures of Penicillium echinulatum 9A02S1. Because cellulose is an insoluble carbon source, in cellulase production, there are some problems with rheology and oxygen transfer. The submerged fermentations containing media composed of 0, 0.25, 0.5, 0.75, and 1% (w/v) sorbitol and cellulose that were added at different times during the cultivation; 0.2% (w/v) soy bran; 0.1% (w/v) wheat bran; and a solution of salts. The highest filter paper activity (FPA) (1.95  ±  0.04 IU·mL(-1)) was obtained on the seventh day in the medium containing 0.5% (w/v) sorbitol and 0.5% (w/v) cellulose added 24 h after the start of cultivation. However, the CMCases showed an activity peak on the sixth day (9.99 ± 0.75 IU·mL(-1)) in the medium containing 0.75% (w/v) sorbitol and 0.75% (w/v) cellulose added after 12 h of cultivation. The xylanases showed the highest activity in the medium with 0.75% (w/v) sorbitol and 0.25% (w/v) cellulose added 36 h after the start of cultivation. This strategy enables the reduction of the cellulose concentration, which in high concentrations can cause rheological and oxygen transfer problems.

  13. Purification and characterization of a new Xylanase from Humicola grisea var. Thermoidea Produção, purificação e caracterização de uma nova Xilanase de Humicola grisea var. Thermoidea

    OpenAIRE

    Severino de Albuquerque Lucena-Neto; Edivaldo Ximenes Ferreira-Filho

    2004-01-01

    The thermophilic fungus Humicola grisea var. thermoidea secretes extracellular xylanase when grown on solid and in liquid media containing wheat bran and banana plant residue as substrates, respectively. At 55ºC, xylanase from the culture filtrate of H. grisea var. thermoidea grown on banana stalk retained 50% of its activity after 28 h of incubation. A xylanase (X2) was isolated from solid state cultures with wheat bran as the carbon source. It was purified to apparent homogeneity by ultrafi...

  14. Insight into structure and assembly of the nuclear pore complex by utilizing the genome of a eukaryotic thermophile

    DEFF Research Database (Denmark)

    Amlacher, Stefan; Sarges, Phillip; Flemming, Dirk;

    2011-01-01

    Despite decades of research, the structure and assembly of the nuclear pore complex (NPC), which is composed of ~30 nucleoporins (Nups), remain elusive. Here, we report the genome of the thermophilic fungus Chaetomium thermophilum (ct) and identify the complete repertoire of Nups therein. The the...... of a thermophilic eukaryote for studying complex molecular machines....

  15. Production of xylan degrading endo-1, 4-β-xylanase from thermophilic Geobacillus stearothermophilus KIBGE-IB29

    Directory of Open Access Journals (Sweden)

    Zainab Bibi

    2014-10-01

    Full Text Available Xylan degrading bacterial strain was isolated from soil and identified as Geobacillus stearothermophilus KIBGE-IB29 on the basis of morphological, biochemical and 16S rDNA sequence analysis. Optimization of medium and culture conditions in submerged fermentation was investigated for maximum endo-1, 4-β-xylanase production. High yield of xylan degrading endo-1, 4-β-xylanase was achieved at 60 °C and pH-6.0 with 24 h of fermentation. Maximum enzyme was produced using 0.5% xylan as a carbon source, 0.5% peptone, 0.2% yeast extract and 0.1% meat extract as nitrogen sources. Di-potassium hydrogen phosphate (0.25%, calcium chloride (0.01%, potassium hydrogen phosphate (0.05% and ammonium sulfate (0.05% were also incorporated in the fermentation medium to enhance the enzyme production.

  16. Evaluation of operational parameters on the precipitation of endoglucanase and xylanase produced by solid state fermentation of Aspergillus niger

    Directory of Open Access Journals (Sweden)

    C. S. Farinas

    2011-03-01

    Full Text Available In order to develop cost effective processes for converting biomass into biofuels, it is essential to improve enzyme production yields, stability and specific activity. In this context, the aim of this work was to evaluate the concentration of two enzymes involved in the hydrolysis of biomass, endoglucanase and xylanase, through precipitation. Statistical experimental design was used to evaluate the influence of precipitant agent concentration (ammonium sulfate and ethanol, aging time, and temperature on enzyme activity recovery. Precipitant agent concentration and aging time showed a statistically significant effect at the 95% confidence level, on both enzyme activity recoveries. The recovery of endoglucanase with ammonium sulfate and ethanol reached values up to 65 and 61%, respectively. For xylanase, the recovery rates were lower, 27 and 25% with ammonium sulfate and ethanol, respectively. The results obtained allowed the selection of the variables relevant to improving enzyme activity recovery within operational conditions suitable for industrial applications.

  17. Partial purification and properties of cellulase-free alkaline xylanase produced by Rhizopus stolonifer in solid-state fermentation

    OpenAIRE

    Antonio José Goulart; Eleonora Cano Carmona; Rubens Monti

    2005-01-01

    Rhizopus stolonifer was cultivated in wheat bran to produce a cellulase-free alkaline xylanase. The purified enzyme obtained after molecular exclusion chromatography in Sephacryl S-200 HR showed optimum temperature as 45º C and hydrolysis pHs optima as pH 6.0 and 9.0. Xylanase presented higher Vmax at pH 9.0 (0.87 µmol/mg protein) than at pH 6.0 and minor Km at pH 6.0 (7.42 mg/mL) than at pH 9.0.Rhizopus stolonifer foi cultivado em meio de farelo de trigo para produzir uma xilanase alcalina c...

  18. Properties of an alkali-thermo stable xylanase from Geobacillus thermodenitrificans A333 and applicability in xylooligosaccharides generation.

    Science.gov (United States)

    Marcolongo, Loredana; La Cara, Francesco; Morana, Alessandra; Di Salle, Anna; Del Monaco, Giovanni; Paixão, Susana M; Alves, Luis; Ionata, Elena

    2015-04-01

    An extracellular thermo-alkali-stable and cellulase-free xylanase from Geobacillus thermodenitrificans A333 was purified to homogeneity by ion exchange and size exclusion chromatography. Its molecular mass was 44 kDa as estimated in native and denaturing conditions by gel filtration and SDS-PAGE analysis, respectively. The xylanase (GtXyn) exhibited maximum activity at 70 °C and pH 7.5. It was stable over broad ranges of temperature and pH retaining 88 % of activity at 60 °C and up to 97 % in the pH range 7.5-10.0 after 24 h. Moreover, the enzyme was active up to 3.0 M sodium chloride concentration, exhibiting at that value 70 % residual activity after 1 h. The presence of other metal ions did not affect the activity with the sole exceptions of K(+) that showed a stimulating effect, and Fe(2+), Co(2+) and Hg(2+), which inhibited the enzyme. The xylanase was activated by non-ionic surfactants and was stable in organic solvents remaining fully active over 24 h of incubation in 40 % ethanol at 25 °C. Furthermore, the enzyme was resistant to most of the neutral and alkaline proteases tested. The enzyme was active only on xylan, showing no marked preference towards xylans from different origins. The hydrolysis of beechwood xylan and agriculture-based biomass materials yielded xylooligosaccharides with a polymerization degree ranging from 2 to 6 units and xylobiose and xylotriose as main products. These properties indicate G. thermodenitrificans A333 xylanase as a promising candidate for several biotechnological applications, such as xylooligosaccharides preparation.

  19. One-step purification and characterization of cellulase-free xylanase produced by alkalophilic Bacillus subtilis ash

    Directory of Open Access Journals (Sweden)

    Ashwani Sanghi

    2010-06-01

    Full Text Available The present study describes the one-step purification and characterization of an extracellular cellulase-free xylanase from a newly isolated alkalophilic and moderately thermophilic strain of Bacillus subtilis ASH. Xylanase was purified to homogeneity by 10.5-fold with ~43% recovery using ion-exchange chromatography through CM-Sephadex C-50. The purified enzyme revealed a single band on SDS-PAGE gel with a molecular mass of 23 kDa. It showed an optimum pH at 7.0 and was stable over the pH range 6.0-9.0. The optimum temperature for enzyme activity was 55 ºC. The purified xylanase did not lose any activity up to 45 ºC, however, it retained 80% and 51% of its activity after pre-incubation at 55 ºC and 60 ºC, respectively. The enzyme obeyed Michaelis-Menton kinetics towards birch wood xylan with apparent Km 3.33 mg/ml and Vmax 100 IU/ml. The enzyme was strongly inhibited by Hg2+ and Cu2+ while enhanced by Co2+ and Mn2+. The purified enzyme could be stored at 4 ºC for six weeks without any loss of catalytic activity. The faster and economical purification of the cellulase-free xylanase from B. subtilis ASH by one-step procedure together with its appreciable stability at high temperature and alkaline pH makes it potentially effective for industrial applications.

  20. Characterization of a purified thermostable xylanase from Caldicoprobacter algeriensis sp. nov. strain TH7C1(T).

    Science.gov (United States)

    Amel, Bouanane-Darenfed; Nawel, Boucherba; Khelifa, Bouacem; Mohammed, Gagaoua; Manon, Joseph; Salima, Kebbouche-Gana; Farida, Nateche; Hocine, Hacene; Bernard, Ollivier; Jean-Luc, Cayol; Marie-Laure, Fardeau

    2016-01-01

    The present study investigates the purification and biochemical characterization of an extracellular thermostable xylanase (called XYN35) from Caldicoprobacter algeriensis sp. nov., strain TH7C1(T), a thermophilic, anaerobic strain isolated from the hydrothermal hot spring of Guelma (Algeria). The maximum xylanase activity recorded after 24 h of incubation at 70 °C and in an optimized medium containing 10 g/L mix birchwood- and oats spelt-xylan was 250 U/mL. The pure protein was obtained after heat treatment (1 h at 70 °C), followed by sequential column chromatographies on Sephacryl S-200 gel filtration and Mono-S Sepharose anion-exchange. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis indicated that the purified enzyme is a monomer with a molecular mass of 35,075.10 Da. The results from amino-acid sequence analysis revealed high homology between the 21 NH2-terminal residues of XYN35 and those of bacterial xylanases. The enzyme showed optimum activity at pH 11 and 70 °C. While XYN35 was activated by Ca(2+), Mn(2+), and Mg(2+), it was completely inhibited by Hg(2+) and Cd(2+). The xylanase showed higher specific activity on soluble oat-spelt xylan, followed by beechwood xylan. This enzyme was also noted to obey the Michaelis-Menten kinetics, with Km and kcat values on oat-spelt xylan being 1.33 mg/mL and 400 min(-1), respectively. Thin-layer chromatography soluble oat-spelt xylan (TLC) analysis showed that the final hydrolyzed products of the enzyme from birchwood xylan were xylose, xylobiose, and xylotriose. Taken together, the results indicated that the XYN35 enzyme has a number of attractive biochemical properties that make it a potential promising candidate for future application in the pulp bleaching industry. PMID:26687892

  1. Identification of glutamic acid 78 as the active site nucleophile in Bacillus subtilis xylanase using electrospray tandem mass spectrometry.

    Science.gov (United States)

    Miao, S; Ziser, L; Aebersold, R; Withers, S G

    1994-06-14

    A new mechanism-based inactivator of beta-1,4-xylanases, 2',4'-dinitrophenyl 2-deoxy-2-fluoro-beta-xylobioside, has been synthesized and used to trap the covalent intermediate formed during catalysis by Bacillus subtilis xylanase. Electrospray mass spectrometry confirmed the 1:1 stoichiometry of the incorporation of inactivator into the enzyme. Inactivation of xylanase followed the expected pseudo-first-order kinetic behavior, and kinetic parameters were determined. The intermediate trapped was relatively stable toward hydrolytic turnover (t1/2 = 350 min). However, turnover could be facilitated by transglycosylation following the addition of the acceptor benzyl thio-beta-xylobioside, thus demonstrating the catalytic competence of the trapped intermediate. Reactivation kinetic parameters for this process of kre = 0.03 min-1 and Kre = 46 mM were determined. The nucleophilic amino acid was identified as Glu78 by a tandem mass spectrometric technique which does not require the use of radiolabels. The peptic digest of the labeled enzyme was separated by high-performance liquid chromatography and the eluent fed into a tandem mass spectrometer via an electrospray ionization device. The labeled peptide was identified as one of m/z = 826 (doubly charged) which fragmented in the collision chamber between the mass analyzers with loss of the mass of a 2-fluoroxylobiosyl unit. Confirmation of the peptide identity was obtained both by tandem mass spectrometric sequencing and by Edman degradation of the purified peptide. Glu78 is completely conserved in all members of this xylanase family and indeed is shown to be located in the active site in the recently determined X-ray crystal structure.

  2. STUDIES ON XYLANASE AND LACCASE ENZYMATIC PREBLEACHING TO REDUCE CHLORINE-BASED CHEMICALS DURING CEH AND ECF BLEACHING

    Directory of Open Access Journals (Sweden)

    Vasanta V. Thakur,

    2012-02-01

    Full Text Available The biobleaching efficiency of xylanase and laccase enzymes was studied on kraft pulps from wood and nonwood based raw materials employed in the Indian paper industry. Treatment of these pulps with xylanase enzyme could result in improved properties, showing 2.0% ISO gain in pulp brightness and/or reducing the demand of chlorine-based bleach chemicals by up to 15% with simultaneous reduction of 20 to 25% in AOX generation in bleach effluents. Further, mill-scale trial results revealed that enzymatic prebleaching can be successfully employed with xylanases to reach the same bleach boosting efficacy. Laccase bleaching was also studied on hardwood pulp at a pH around 8.0, where most of the pulp mills in India are operating, in contrast to earlier studies on laccase enzyme bleaching, which were conducted at acidic pHs, i.e. 4.0 to 5.0. In case of laccase bleaching, interesting results were found wherein a bleach-boosting effect was observed even at pH 8.0. Further studies carried out with HOBT as mediator in comparison to the commonly used and expensive ABTS laccase mediator system (LMS resulted in improvement of the bleaching efficiency with reduction in demand of chlorine dioxide by more than 35%. Potential for further reduction was indicated by the brightness gain, when compared with a control using the DE(pD bleach sequence.

  3. Effect of Temperature on Xylanase II from Trichoderma reesei QM 9414: A Calorimetric, Catalytic, and Conformational Study

    Directory of Open Access Journals (Sweden)

    Gloria López

    2014-01-01

    Full Text Available The secondary structure of xylanase II from Trichoderma reesei is lost in an apparent irreversible cooperative process as temperature is increased with a midpoint transition of 58.8 ± 0.1°C. The shift of the spectral centre of mass above 50°C is also apparently cooperative with midpoint transition of 56.3 ± 0.2°C, but the existence of two isofluorescent points in the fluorescence emission spectra suggests a non-two-state process. Further corroboration comes from differential scanning calorimetry experiments. At protein concentrations ≤0.56 mg·mL−1 the calorimetric transition is reversible and the data were fitted to a non-two-state model and deconvoluted into six transitions, whereas at concentrations greater than 0.56 mg·mL−1 the calorimetric transition is irreversible with an exothermic contribution to the thermogram. The apparent Tm increased linearly with the scan rate according to first order inactivation kinetics. The effect of additives on the calorimetric transition of xylanase is dependent on their nature. The addition of sorbitol transforms reversible transitions into irreversible transitions while stabilizing the protein as the apparent Tm increases linearly with sorbitol concentration. d-Glucono-1,5-lactone, a noncompetitive inhibitor in xylanase kinetics, and soluble xylan change irreversible processes into reversible processes at high protein concentration.

  4. Recombination of thermo-alkalistable, high xylooligosaccharides producing endo-xylanase from Thermobifida fusca and expression in Pichia pastoris.

    Science.gov (United States)

    Wang, Qian; Du, Wen; Weng, Xiao-Yan; Liu, Ming-Qi; Wang, Jia-Kun; Liu, Jian-Xin

    2015-02-01

    For xylooligosaccharide (XO) production, endo-xylanase from Thermobifida fusca was modified by error-prone PCR and DNA shuffling. The G4SM1 mutant (S62T, S144C, N198D, and A217V) showed the most improved hydrolytic activity and was two copies expressed in Pichia pastoris under the control of GAP promoter. The maximum xylanase activity in culture supernatants was 165 ± 5.5 U/ml, and the secreted protein concentration reached 493 mg/l in a 2-l baffled shake flask. After 6× His-tagged protein purification, the specific activity of G4SM1 was 2036 ± 45.8 U/mg, 2.12 times greater than that of wild-type enzyme. Additionally, G4SM1 was stable over a wide pH range from 5.0 to 9.0. Meanwhile, half-life of G4SM1 thermal inactivation at 70 °C increased 8.5-fold. Three-dimensional structures suggest that two amino acid substitutions, S62T and S144C, located at catalytic domain may be responsible for the enhanced activity and thermostability of xylanase. Xylobiose was the dominant end product of xylan hydrolysis by G4SM1. Due to its attractive biochemical properties, G4SM1 has potential value in commercial XO production. PMID:25384545

  5. High-level expression and characterization of a thermostable xylanase mutant from Trichoderma reesei in Pichia pastoris.

    Science.gov (United States)

    Li, Yang-yuan; Zhong, Kai-xin; Hu, Ai-hong; Liu, Dan-ni; Chen, Li-zhi; Xu, Shu-de

    2015-04-01

    A gene encoding xylanase 2 mutant from Trichoderma reesei (T2C/T28C, named mxyn2) was cloned into the Pichia pastoris X33 strain using the vector pPICZαA. Recombinant Mxyn2p was functionally expressed in P. pastoris X33 and secreted into the supernatant. Real time qPCR demonstrated that an increase in gene copy number correlated with higher levels of expression. Supernatant from methanol induced cells was concentrated by ultrafiltration with a 10kDa cut off membrane, and purified with ion exchange chromatography using SP Sepharose Fast Flow chromatography. Recombinant Mxyn2p protein had the highest activity at 75°C, while recombinant protein encoded by the "wild type" xylanase gene xyn2, also expressed in Pichia, was 20°C lower. The Mxyn2p enzyme retained more than 70% of its activity after incubation at 80°C for 10min. The effects of the optimal pH and temperature for higher expression levels in P. pastoris were also determined, 6.0 and 22°C, respectively. The maximum xylanase activity of Mxyn2p was 13,000nkat/mg (9.88g/l) in fed-batch cultivation after 168h induction with methanol in a 50l bioreactor. PMID:25434687

  6. A novel low molecular weight endo-xylanase from Streptomyces sp. CS628 cultivated in wheat bran.

    Science.gov (United States)

    Rahman, Md Arifur; Choi, Yun Hee; Pradeep, G C; Choi, Yoon Seok; Choi, Eun Joo; Cho, Seung Sik; Yoo, Jin Cheol

    2014-07-01

    An extracellular low molecular weight xylanase (Xyn628) from Streptomyces sp. CS628 was isolated from Korean soil sample, produced in wheat bran medium, purified, and biochemically characterized. Xyn628 was purified 4.8-fold with a 33.78 % yield using Sepharose CL-6B column chromatography. The purified xylanase was ~18.1 kDa estimated by SDS-PAGE and xylan zymography. N-terminal amino acid sequences of Xyn628 were AYIKEVVSRAYM. The enzyme was found to be stable in a broad range of pH (5.0-13.0) and up to 60 °C and have optimal pH and temperature of pH 11.0 and 60 °C, respectively. Xyn628 activities were remarkable affected by various detergents, chelators, modulators, and metal ions. The xylanase produced xylobiose and xylotriose as principal hydrolyzed end products from the xylan. It was found to degrade agro-waste materials like corn cob and wheat bran by Xyn628 (20 U/g) as shown by electron microscopy. As being simple in purification, low molecular weight, alkaline, thermostable, and ability to produce xylooligosaccharides show that Xyn628 has potential applications in bioindustries as a biobleaching agent or/and xylooligosaccharides production with an appropriate utilization of agro-waste. PMID:24817510

  7. Cloning and expression of a novel, moderately thermostable xylanase-encoding gene (Cflxyn11A) from Cellulomonas flavigena.

    Science.gov (United States)

    Amaya-Delgado, Lorena; Mejía-Castillo, Teresa; Santiago-Hernández, Alejandro; Vega-Estrada, Jesús; Amelia, Farrés-G-S; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto; Montes-Horcasitas, María Del Carmen; Hidalgo-Lara, María Eugenia

    2010-07-01

    The Cfl xyn11A gene, encoding the endo-1,4-beta-xylanase Cfl Xyn11A from Cellulomonas flavigena, was isolated from a genomic DNA library. The open reading frame of the Cfl xyn11A gene was 999 base pairs long and encoded a polypeptide (Cfl Xyn11A) of 332 amino acids with a calculated molecular mass of 35,110Da. The Cfl xyn11A gene was expressed in Escherichia coli and the recombinant enzyme, with an estimated molecular weight of 31kDa was purified and xylanase activity was measured. Cfl Xyn11A showed optimal activity at pH 6.5 and 55 degrees C. The enzyme demonstrated moderate thermal stability as Cfl Xyn11A maintained 50% of its activity when incubated at 55 degrees C for 1h or at 45 degrees C for 6h. This is the first report describing the cloning, expression and functional characterization of an endo-1,4-beta-xylanase-encoding gene from C. flavigena. Cfl Xyn11A may be suitable for industrial applications in the food and feed industries, or in the pre-treatment of lignocellulosic biomass required to improve the yields of fermentable sugars for bioethanol production. PMID:20231092

  8. A xylanase from Streptomyces sp. FA1: heterologous expression, characterization, and its application in Chinese steamed bread.

    Science.gov (United States)

    Xu, Yang; Wu, Jing; Zheng, Kaixuan; Wu, Dan

    2016-05-01

    Xylanases (EC 3.2.1.8) are hydrolytic enzymes that have found widespread application in the food, feed, and paper-pulp industries. Streptomyces sp. FA1 xynA was expressed as a secreted protein in Pichia pastoris, and the xylanase was applied to the production of Chinese steamed bread for the first time. The optimal pH and the optimal temperature of XynA were 5.5 and 60 °C, respectively. Using beechwood as substrate, the K m and V max were 2.408 mg mL(-1) and 299.3 µmol min(-1) mg(-1), respectively. Under optimal conditions, a 3.6-L bioreactor produced 1374 U mL(-1) of XynA activity at a protein concentration of 6.3 g L(-1) after 132 h of fermentation. Use of recombinant XynA led to a greater increase in the specific volume of the CSB than could be achieved using commercial xylanase under optimal conditions. This study provides the basis for the application of the enzyme in the baking industry. PMID:26803505

  9. Expression of an alkalo-tolerant fungal xylanase enhanced by directed evolution in Pichia pastoris and Escherichia coli.

    Science.gov (United States)

    McHunu, Nokuthula Peace; Singh, Suren; Permaul, Kugen

    2009-04-20

    The alkaline stability of the xylanase from Thermomyces lanuginosus was further improved by directed evolution using error-prone PCR mutagenesis. Positive clones were selected by their ability to produce zones of clearing on pH 9 and 12 xylan agar plates. Variant NC38 was able to withstand harsh alkaline conditions retaining 84% activity after exposure at pH 10 for 90 min at 60 degrees C, while the parent enzyme had 22% activity after 60 min. The alkaline stable variant NC38 was cloned into pBGP1 under the control GAP promoter and pET22b(+) for expression in Pichia pastoris and Escherichia coli BL21, respectively. Best extracellular expression of the recombinant xylanase was observed in P. pastoris (261.7+/-0.61 U ml(-1)) whereas intracellular activity was observed in E. coli (47.9+/-0.28 U ml(-1)) was low. Total activity obtained in P. pastoris was 545-fold higher than E. coli. The mutated alkaline stable xylanase from P. pastoris was secreted into the culture medium with little or no contamination by host proteins, which favours the application of this enzyme in the pulp and paper industry. PMID:19428727

  10. CLONING, EXPRESSION, AND CHARACTERIZATION OF AN ALKALOPHILLIC ENDO-1,4-BETA-XYLANASE FROM PAENIBACILLUS SP. HPL-002

    Directory of Open Access Journals (Sweden)

    No-Joong Park,

    2011-12-01

    Full Text Available The biochemical properties of a purified enzyme of a new alkalophillic endo-1,4-beta-xylanase gene, KRICT PX2 (GU967374, which was isolated from Paenibacillus sp. HPL-002 (KCTC11410BP and expressed in E. coli, were investigated. The specific activity of the purified xylanase was 51.26 μmol/min/mg proteins. The Km and Vmax values of the protein for birch wood xylan were also verified to have 0.061 μM and 55.3 μmol/min/mg proteins, respectively. The optimum pH and temperature for the activity of the enzyme were pH 8~9 and 50oC, respectively, and, the activity was stably maintained at 40oC. Most metallic salts, ethylenediamine tetra-acetic acid, 2-mercaptoethanol, phenylmethane-sulphonyl fluoride, and furfural, have no impact on the enzyme’s activity at 1 mM. The simulated 3-D structure of this xylanase is similar to Xyn10B from Paenibacillus barcinonensis. Further research on the degradation of different-origin xylans and enzyme production will be necessary for practical applications.

  11. Cellulase and xylanase productions by isolated Amazon Bacillus strains using soybean industrial residue based solid-state cultivation

    Directory of Open Access Journals (Sweden)

    Heck Júlio X.

    2002-01-01

    Full Text Available In Brazil, a large amount of a fibrous residue is generated as result of soybean (Glycine max protein production. This material, which is rich in hemicellulose and cellulose, can be used in solid state cultivations for the production of valuable metabolites and enzymes. In this work, we studied the bioconversion of this residue by bacteria strains isolated from water and soil collected in the Amazon region. Five strains among 87 isolated bacteria selected for their ability to produce either celullases or xylanases were cultivated on the aforementioned residue. From strain BL62, identified as Bacillus subtilis, it was obtained a preparation showing the highest specific cellulase activity, 1.08 UI/mg protein within 24 hours of growth. Concerning xylanase, the isolate BL53, also identified as Bacillus subtilis, showed the highest specific activity for this enzyme, 5.19 UI/mg protein within 72 hours of cultivation. It has also been observed the production of proteases that were associated with the loss of cellulase and xylanase activities. These results indicated that the selected microorganisms, and the cultivation process, have great biotechnological potential.

  12. Determination of the modes of action and synergies of xylanases by analysis of xylooligosaccharide profiles over time using fluorescence-assisted carbohydrate electrophoresis.

    Science.gov (United States)

    Gong, Weili; Zhang, Huaiqiang; Tian, Li; Liu, Shijia; Wu, Xiuyun; Li, Fuli; Wang, Lushan

    2016-07-01

    The structure of xylan, which has a 1,4-linked β-xylose backbone with various substituents, is much more heterogeneous and complex than that of cellulose. Because of this, complete degradation of xylan needs a large number of enzymes that includes GH10, GH11, and GH3 family xylanases together with auxiliary enzymes. Fluorescence-assisted carbohydrate electrophoresis (FACE) is able to accurately differentiate unsubstituted and substituted xylooligosaccharides (XOS) in the heterogeneous products generated by different xylanases and allows changes in concentrations of specific XOS to be analyzed quantitatively. Based on a quantitative analysis of XOS profiles over time using FACE, we have demonstrated that GH10 and GH11 family xylanases immediately degrade xylan into sizeable XOS, which are converted into smaller XOS in a much lower speed. The shortest substituted XOS produced by hydrolysis of the substituted xylan backbone by GH10 and GH11 family xylanases were MeGlcA(2) Xyl3 and MeGlcA(2) Xyl4 , respectively. The unsubstituted xylan backbone was degraded into xylose, xylobiose, and xylotriose by both GH10 and GH11 family xylanases; the product profiles are not family-specific but, instead, depend on different subsite binding affinities in the active sites of individual enzymes. Synergystic action between xylanases and β-xylosidase degraded MeGlcA(2) Xyl4 into xylose and MeGlcA(2) Xyl3 but further degradation of MeGlcA(2) Xyl3 required additional enzymes. Synergy between xylanases and β-xylosidase was also found to significantly accelerate the conversion of XOS into xylose. PMID:27060349

  13. Preservation of Bacillus pumilus PU4-2 xylanases by immobilization technique into pollard and cation addition

    Directory of Open Access Journals (Sweden)

    T Haryati

    2010-03-01

    Full Text Available Utilization of by-product from agriculture as alternative source of feedstuff has been widely practiced. However their usage is limited due to high fiber content and low nutrient digestibility. The use of specific hydrolizing enzymes, xylanases are gaining importance because of their wide application in various industrial sectors especially in bioconversion of hemicellulosic material. This experiment was done to evaluate the effect of cation addition and immobilization of enzyme into pollard on stability of B. pumilus xylanase. The enzyme extract was purified by precipitation with 75% ammonium sulphate. Four kinds of cation (Ca2+, Fe3+, Mg2+, Zn2+ were added to the purified enzyme, at concentration of 1m M and stored at 4 and 27˚C. For immobilization process, the optimum enzyme concentration that will be added to pollard has been evaluated by analysis of xylanase activity and their recovery. The specific activity of enzyme after precipitation increased 1.8 times, from 420.3 to 765.2 U/mg protein. All cations act as activator which relative activity become 130.6; 139.0; 103.8 and 163.5% respectively. Concentration of 0.5mM Ca2+ and Fe3+ were most able to keep xylanases activity stable at 4˚C. The optimum composition of enzymes and pollard was 1.5 ml for 5 gram of pollard with recovery of xylanases activity of 82.2%. In immobilized enzyme, the activity of enzyme without cation addition is higher than that with addition of Ca2+ and Fe3+. Activity of enzyme stored at 4˚C is more stable than that at 27˚C. Immobilized enzyme is more stable for storage, which lasted for 7 weeks at 27˚C and 12 weeks at 4˚C compared to liquid enzyme which lasted for only 7 days at 27˚C and 13 days at 4˚C.

  14. Decolorization of four dyes by a mixed culture of Trametes sp. SQO1 and Chaetomium sp. RO1%Trametes sp.SQ01和Chaetomium sp.R01混合培养对四种染料的脱色

    Institute of Scientific and Technical Information of China (English)

    杨秀清; 王婧人; 赵晓霞; 薛瑞

    2011-01-01

    Four dyes including Congo red, acid red, orange G and bromphenol blue were decolorized by a mixed fungal culture of Trametes sp. SQO 1 and Chaetomium sp. R0I, which were newly developed in our laboratory. The results indicated that MnP activity in the mixed culture of strain S001 and R0I increased approximately 5.5 times over that obtained from a pure culture of SQOI. The amount and timing of strain R01 had a marked effect on MnP production by SQOI. If the inoculum of strain ROI was too high or too low, the MnP activity decreased in the mixed culture. As the inoculation time of strain R01 was delayed, MnP activity was gradually reduced. MnP production was inhibited by about 40% ~75% by the four dyes in mixed culture of SQOI and R01. The decolorization rates of mixed culture of strain SQ01 and R01 were increased by 20% ~ 50% compared to that of the monoculture of SQOI. After 3 days, 75% ~94% of four dyes were decolorized by mixed culture of SQ01 and R01 ,while the decolorization rate was only about 41% 75% by strain SQ01 cultured alone. The time-point of dye addition remarkably influenced the efficiency of decolorization by the mixed culture. The decolorization rates of dyes added to the medium after 4 days of mixed cultivation were significantly higher as compared to dyes added at the outset of mixed cultivation. In addition to biodegradation, biosorption also played an important role in the decoiorization process. The biosorption of orange G, bromphenol blue and acid red accounted for 2% ,5% and 15% of the total color removal,respectively. However,the biosorption rate of congo red reached up to 60%.To date, this is the first report of decolorizing dyes by mixed fungal cultures. The high efficiency of the decolorization ability indicates that the mixed culture has broad application prospects in dye decolorization treatment.%利用本实验室新构建的白腐菌Trametes sp.SQ01和毛壳菌Chaetomium sp.R01混合培养体系,对刚

  15. Assay Methods and Unit Definitions of Xylanase Activity%木聚糖酶酶活性测定方法及酶活性单位定义

    Institute of Scientific and Technical Information of China (English)

    王晓丹; 郭丽琼; 赵力超; 林俊芳

    2009-01-01

    The definition and determination of xylanase activity was unified in this article. Through summarizing and comparing the present knowledge on different procedure for the determination of xylanase activity,one unit of xylanase activity was defined as the quantity of enzyme required to liberate 1 (xmol of reducing sugar ( as xylose) per minute at the measure conditions . This DNS method of expressing xylanase activity is scientifically sound and we suggest that this method be utilized as the universal and standard method of determining xylanase activity.%为统一木聚糖酶酶活性的单位定义及测定方法进行了实验.通过对现有酶活性的单位定义及测定方法的比较分析,得出木聚糖酶的酶活性单位定义为:在特定条件下,每分钟水解木聚糖形成1μmol木糖(还原糖)所需酶量为1个酶活力单位(U),并且采用还原糖法中的DNS法作为测定木聚糖酶酶活性的方法,该法具有合理性和科学性,建议以此作为木聚糖酶酶活性测定及酶活性单位定义的统一方法.

  16. OPTIMIZATION OF CELLULASE-FREE XYLANASE PRODUCED BY A POTENTIAL THERMOALKALOPHILIC PAENIBACILLUS SP.N1 ISOLATED FROM HOT SPRINGS OF NORTHERN HIMALAYAS IN INDIA

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar Verma

    2012-08-01

    Full Text Available Hot spring bacteria are found a novel source of highly active xylanase enzyme with significant activity at high temperature. Among bacteria, Paenibacillus sp.N1 isolated from hot water spring of Manikaran, H.P., India showed highest 24.60 IU.ml-1 of cellulase-free xylanase on Reese medium. Growth conditions including medium, incubation time, pH, temperature, inoculum size, aminoacids, carbon sources, nitrogen sources and additives that affect the xylanase production by Paenibacillus sp.N1 were studied sequentially using the classical “change-one factor at a time” method. The optimal cultivation conditions predicated from canonical analysis of this model were achieved by using basal salt medium on 3rd day, pH 9.0, temperature 50ºC with inoculum size of 12.5%, phenylalanine as aminoacid, xylose as carbon source, (NH42HPO4 as nitrogen source and Tween 20 as detergent added with an approximate yield of 52.30 IU.ml-1 escalating the over level of xylanase production by 113.38%. A rare combination of all characters i.e. thermoalkalophilic nature and high units of cellulase-free xylanase produced from a new Paenibacillus sp.N1 make it of special industrial interest.

  17. A highly thermostable alkaline cellulase-free xylanase from thermoalkalophilic Bacillus sp. JB 99 suitable for paper and pulp industry: purification and characterization.

    Science.gov (United States)

    Shrinivas, Dengeti; Savitha, Gunashekaran; Raviranjan, Kumar; Naik, Gajanan Ramchandra

    2010-11-01

    A highly thermostable alkaline xylanase was purified to homogeneity from culture supernatant of Bacillus sp. JB 99 using DEAE-Sepharose and Sephadex G-100 gel filtration with 25.7-fold increase in activity and 43.5% recovery. The molecular weight of the purified xylanase was found to be 20 kDA by SDS-PAGE and zymogram analysis. The enzyme was optimally active at 70 °C, pH 8.0 and stable over pH range of 6.0-10.0.The relative activity at 9.0 and 10.0 were 90% and 85% of that of pH 8.0, respectively. The enzyme showed high thermal stability at 60 °C with 95% of its activity after 5 h. The K (m) and V (max) of enzyme for oat spelt xylan were 4.8 mg/ml and 218.6 µM min(-1) mg(-1), respectively. Analysis of N-terminal amino acid sequence revealed that the xylanase belongs to glycosyl hydrolase family 11 from thermoalkalophilic Bacillus sp. with basic pI. Substrate specificity showed a high activity on xylan-containing substrate and cellulase-free nature. The hydrolyzed product pattern of oat spelt xylan on thin-layer chromatography suggested xylanase as an endoxylanase. Due to these properties, xylanase from Bacillus sp. JB 99 was found to be highly compatible for paper and pulp industry.

  18. Cloning and constitutive expression of His-tagged xylanase GH 11 from Penicillium occitanis Pol6 in Pichia pastoris X33: purification and characterization.

    Science.gov (United States)

    Driss, Dorra; Bhiri, Fatma; Ghorbel, Raoudha; Chaabouni, Semia Ellouz

    2012-05-01

    High-level constitutive expression of xylanase GH11 from Penicillium occitanis Pol6 termed PoXyn2 was achieved using the methylotrophic yeast Pichia pastoris. The PoXyn2 cDNA encoding for a mature xylanase of 320 amino acids was subcloned into the pGAPZαA vector, to construct recombinant xylanse with six histidine residues at the N-terminal and further integrated into the genome of P. pastoris X-33 under the control of the glyceraldehyde 3-phosphate dehydrogenase (GAP) constitutive promoter. Activity assay and SDS-PAGE demonstrate that the His-tagged xylanase was extracellularly expressed in P. pastoris and purified to homogeneity by a simple, one-step purification protocol using immobilized metal affinity chromatography (Ni-NTA resin). The purified PoXyn2 showed a single band on SDS-PAGE with an apparent molecular weight of 30 kDa. The xylanase activity was optimal at pH 3.0 and 50°C. The specific activity measured for Oat Spelt Xylan was 8549.85 U mg(-1). The apparent The K(M) and V(max) values were 8.33±0.7 mg ml(-1)and 58.82±0.9 μmol min(-1) ml(-1), respectively, as measured on Oat Spelt Xylan. This is the first report demonstrating the possibility of mass production of P. occitanis xylanase using P. pastoris. PMID:22402470

  19. Purification and characterization of cellulase-free low molecular weight endo β-1,4 xylanase from an alkalophilic Cellulosimicrobium cellulans CKMX1 isolated from mushroom compost.

    Science.gov (United States)

    Walia, Abhishek; Mehta, Preeti; Chauhan, Anjali; Kulshrestha, Saurabh; Shirkot, C K

    2014-10-01

    Alkalophilic Cellulosimicrobium cellulans CKMX1 isolated from mushroom compost is first report on actinomycetes that has the ability to produce thermostable cellulase-free xylanase, which is an important industrial enzyme used in the pulp and paper industry. Strain CKMX1 was characterized by metabolic fingerprinting, whole-cell fatty acids methyl ester analysis and 16Sr DNA and found to be C. cellulans CKMX1.The enzyme was purified by gel permeation and anion exchange chromatography and had a molecular mass of 29 kDa. Xylanase activity was optimum at pH 8.0 and 55 °C. The enzyme was somewhat thermostable, retaining 50 % of the original activity after incubation at 50 °C for 30 min. The xylanase had K m and V max values of 2.64 mg/ml and 2,000 µmol/min/mg protein in oat spelt xylan, respectively. All metal ions except HgCl2, CoCl2 as well as CdCl2 were well tolerated and did not adversely affect xylanase activity. The deduced internal amino acid sequence of C. cellulans CKMX1 xylanase by matrix assisted laser desorption ionization-time of flight mass spectrometry resembled the sequence of β-1,4-endoxylanase, which is a member of glycoside hydrolase family 11. Some of the novel characteristics that make this enzyme potentially effective in xylan biodegradation could be useful for pulp and paper biobleaching are discussed in this manuscript. PMID:24908422

  20. Effects of microbial xylanase on digestibility of dry matter, organic matter, neutral detergent fiber, and energy and the concentrations of digestible and metabolizable energy in rice coproducts fed to weanling pigs.

    Science.gov (United States)

    Casas, G A; Stein, H H

    2016-05-01

    The objective of this experiment was to test the hypothesis that the apparent total tract digestibility (ATTD) of DM, OM, fiber, and GE by weanling pigs and the concentration of DE and ME in full-fat rice bran (FFRB), defatted rice bran (DFRB), brown rice, and broken rice is improved if microbial xylanase is added to the diet. Eighty pigs (13.6 ± 0.8 kg initial BW) were allotted to 10 diets with 8 replicate pigs per diet in a randomized complete block design with 2 blocks of 40 pigs. A basal diet based on corn and soybean meal and 4 diets containing corn, soybean meal, and each of the 4 rice coproducts were formulated. The rice coproducts and corn and soybean meal were the only sources of energy in the diets. Five additional diets that were similar to the initial 5 diets with the exception that they also contained 16,000 units of xylanase (Econase XT-25; AB Vista, Marlborough, UK) were also formulated. All diets also contained 1,500 units of microbial phytase (Quantum Blue 5G; AB Vista). The DE and ME and the ATTD of DM, OM, fiber, and GE in diets and ingredients were calculated using the direct method and the difference method, respectively. Results indicated that the concentrations of DE and ME (DM basis) in FFRB and DFRB increased ( < 0.05) if xylanase was used. Broken rice had a greater ( < 0.05) concentration of DE and ME than FFRB and DFRB if no xylanase was added to the diets, but if xylanase was used, no differences in ME among FFRB, brown rice, and broken rice were observed. The ATTD of DM was greater ( < 0.05) in ingredients with xylanase than in ingredients without xylanase and there was a tendency ( = 0.067) for the ATTD of OM to be greater if xylanase was used. The ATTD of NDF in FFRB was greater ( < 0.05) when xylanase was added than if no xylanase was used, whereas the ATTD of NDF in DFRB was not affected by the addition of xylanase. In conclusion, if no xylanase was used, broken rice and brown rice have greater concentrations of DE and ME than FFRB

  1. Ethanol/Water Pulps From Sugar Cane Straw and Their Biobleaching With Xylanase from Bacillus pumilus

    Science.gov (United States)

    Moriya, Regina Y.; Gonçalves, Adilson R.; Duarte, Marta C. T.

    The influence of independent variables (temperature and time) on the cooking of sugar cane straw with ethanol/water mixtures was studied to determine operating conditions that obtain pulp with high cellulose contents and a low lignin content. An experimental 22 design was applied for temperatures of 185 and 215°C, and time of 1 and 2.5 h with the ethanol/water mixture concentration and constant straw-to-solvent ratio. The system was scaled-up at 200°C cooking temperature for 2 h with 50% ethanol-water concentration, and 1∶10 (w/v) straw-to-solvent ratio to obtain a pulp with 3.14 cP viscosity, 58.09 kappa-number, and the chemical composition of the pulps were 3.2% pentosan and 31.5% lignin. Xylanase from Bacillus pumilus was then applied at a loading of 5-150 IU/g dry pulp in the sugar cane straw ethanol/water pulp at 50°C for 2 and 20 h. To ethanol/water pulps, the best enzyme dosage was found to be 20 IU/g dry pulp at 20 h, and a high enzyme dosage of 150 IU/g dry pulp did not decrease the kappa-number of the pulp.

  2. Ethanol from a biorefinery waste stream: Saccharification of amylase, protease and xylanase treated wheat bran.

    Science.gov (United States)

    Wood, Ian P; Cook, Nicola M; Wilson, David R; Ryden, Peter; Robertson, James A; Waldron, Keith W

    2016-05-01

    Biorefining aims to exploit the full value of plant material by sequentially extracting and valorising its components. Many studies focus on the saccharification of virgin biomass sources, but it may be more efficient to pre-extract high-value components before hydrolysis to fermentable sugars. In the current study, a bran residue from de-starched, protein depleted and xylanase treated wheat bran has been subjected to hydrothermal pretreatment, saccharification and fermentation procedures to convert the residue to ethanol. The most effective pretreatment conditions (>190 °C, 10 min) and saccharification conditions were identified following bench-scale liquid hot water pretreatment. Pre-extraction of enzymatically-hydrolysable starch and xylan reduced the release of furfural production, particularly when lower pretreatment severities were used. Pilot-scale steam explosion of the lignocellulosic residue followed by cellulase treatment and conversion to ethanol at a high substrate concentration (19%) gave an ethanol titre of ≈ 25 g/L or a yield of 93% of the theoretical maximum.

  3. Ethanol from a biorefinery waste stream: Saccharification of amylase, protease and xylanase treated wheat bran.

    Science.gov (United States)

    Wood, Ian P; Cook, Nicola M; Wilson, David R; Ryden, Peter; Robertson, James A; Waldron, Keith W

    2016-05-01

    Biorefining aims to exploit the full value of plant material by sequentially extracting and valorising its components. Many studies focus on the saccharification of virgin biomass sources, but it may be more efficient to pre-extract high-value components before hydrolysis to fermentable sugars. In the current study, a bran residue from de-starched, protein depleted and xylanase treated wheat bran has been subjected to hydrothermal pretreatment, saccharification and fermentation procedures to convert the residue to ethanol. The most effective pretreatment conditions (>190 °C, 10 min) and saccharification conditions were identified following bench-scale liquid hot water pretreatment. Pre-extraction of enzymatically-hydrolysable starch and xylan reduced the release of furfural production, particularly when lower pretreatment severities were used. Pilot-scale steam explosion of the lignocellulosic residue followed by cellulase treatment and conversion to ethanol at a high substrate concentration (19%) gave an ethanol titre of ≈ 25 g/L or a yield of 93% of the theoretical maximum. PMID:26769514

  4. Expression of A. niger US368 xylanase in E. coli: purification, characterization and copper activation.

    Science.gov (United States)

    Elgharbi, Fatma; Hlima, Hajer Ben; Farhat-Khemakhem, Ameny; Ayadi-Zouari, Dorra; Bejar, Samir; Hmida-Sayari, Aïda

    2015-03-01

    The XAn11 cDNA was cloned in pET-28a(+) and the recombinant plasmid was transformed in Escherichia coli. The His-tagged r-XAn11 was purified using Ni-NTA affinity and anion exchange chromatography. The enzyme showed a specific activity of 415.1 U mg(-1) and a molecular mass of 25 kDa. It had an optimal activity at pH 5 and 50°C. It was stable in a wide range of pH and in the presence of some detergents and organic solvents. In the presence of 3mM Cu2+, the relative activity of the His-tagged r-XAn11 was enhanced by 54%. This is the first work reporting that copper is a strong activator for xylanase activity making this enzyme very attractive for future industrial applications. Molecular modeling suggests that the contact region between the catalytic site and the N-terminal His-tag fusion peptide could be responsible for the different behavior of the native and recombinant enzyme toward copper. PMID:25530001

  5. Biosynthesis, purification and characterization of endoglucanase from a xylanase producing strain Aspergillus niger B03

    Directory of Open Access Journals (Sweden)

    Georgi Todorov Dobrev

    2012-03-01

    Full Text Available An extracellular endoglucanase was isolated from the culture liquid of xylanase producing strain Aspergillus niger B03. The enzyme was purified to a homogenous form, using consecutive ultrafiltration, anion exchange chromatography, and gel filtration. Endoglucanase was a monomer protein with a molecular weight of 26,900 Da determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 28,800 Da determined by gel filtration. The optimal pH and temperature values for the enzyme action were 3.5 and 65ºC respectively. Endoglucanase was stable at 40ºC, pH 3.0 for 210 min. The substrate specificity of the enzyme was determined with carboxymethyl cellulose, filter paper, and different glycosides. Endoglucanase displayed maximum activity in the case of carboxymethyl cellulose, with a Km value of 21.01 mg/mL. The substrate specificity and the pattern of substrate degradation suggested that the enzyme is an endoglucanase. Endoglucanase showed a synergism with endoxylanase in corn cobs hydrolysis.

  6. Crystallization and preliminary X-ray analysis of a cold-active endo-β-1,4-d-xylanase from glycoside hydrolase family 8

    International Nuclear Information System (INIS)

    The crystallization and preliminary X-ray analysis of a cold-active endo-β-1,4-d-xylanase is described. The crystals diffracted to 2.7 Å resolution. Endo-β-1,4-d-xylanases are used in a multitude of industrial applications. Native crystals of a cold-adapted xylanase from glycoside hydrolase family 8 were obtained by the vapour-diffusion technique. The crystals belonged to space group I222, with unit-cell parameters a = 46.6, b = 110.8, c = 150.2 Å at 100 K, and diffracted to 2.7 Å resolution at a synchrotron source. The asymmetric unit is likely to contain one molecule, with a VM of 2.07 Å3 Da−1, corresponding to a solvent content of ∼40%

  7. Exogenous dietary xylanase ameliorates viscosity-induced anti-nutritional effects in wheat-based diets for White Pekin ducks (Anas platyrinchos domesticus).

    Science.gov (United States)

    Adeola, Olayiwola; Bedford, Michael R

    2004-07-01

    Nutrient utilisation and growth performance responses of White Pekin ducks (Anas platyrinchos domesticus) offered diets containing low- or high-viscosity wheat supplemented with xylanase were investigated in two studies. In Expt 1, six diets consisting of low-viscosity wheat or high-viscosity wheat supplemented with 0.0, 1.5 or 3.0 g xylanase (2590 units/g)/kg diet were used in a true metabolisable energy (TME) bioassay with eight 8-week-old ducks per diet group. In Expt 2, eight pens of ten 3-d-old ducks per pen for each of six wheat-based diets arranged in a 2 x 3 factorial of low-viscosity or high-viscosity wheat and 0.0, 1.5 or 3.0 g xylanase/kg were used in a 42 d growth study. High-viscosity wheat depressed (Pducks.

  8. Aspects microbiologiques de la production par fermentation solide des endo-beta-1,4-xylanases de moisissures : le cas de Penicillium canescens

    Directory of Open Access Journals (Sweden)

    Assamoi AA.

    2009-01-01

    Full Text Available Microbial aspects of endo-β-1,4-xylanase production in solid-state fermentation by Penicillia: the case of Penicillium canescens. Production of xylanases by Penicillium canescens 10-10c is the research object in Walloon Center of Industrial Biology. Previous works used submerged or liquid fermentation. The actual works are oriented more and more towards solid fermentation from agricultural or agro-alimentary residues. In addition to the valorization of these residues, solid-state fermentation reaches an increasingly significant interest in various other fields like the biological breakdown of the solid residues, the bioremediation of the organic pollutants in the grounds and the reduction of the air pollution by the biofiltration. Xylanase is an industrial enzyme used in general in extraction and clarification processes. P. canescens can produce an activity of it, particularly in its balanced forms of xylanases, beta-xylosidase and arabinosidase, and not contaminated by cellulolytic and amylolytic activities. It is a hyper producing strain of xylanase. The production rate is one of the highest in literature (535 U.ml-1 and 9,632 U.g-1 in Erlenmeyer flasks, in submerged and solid state fermentation, respectively. The biobleaching activity of the cellulose pulp by the purified enzyme is higher than a commercial preparation of xylanases from Trichoderma longibrachiatum used industrially. It has a complete hydrolysis degree of 40% (on glucuronoxylan and 35% (on arabinoxylan at 55°C and at pH of 5.9. These characteristics lead to many industrial applications of this enzyme. That is why the optimization of its production by the solid-state fermentation at the laboratory scale in order to define a policy for the industrial transposition later is carried out. This article presents a summary of the scientific literature on this subject.

  9. The enhancement of enzymatic hydrolysis of lignocellulosic substrates by the addition of accessory enzymes such as xylanase: is it an additive or synergistic effect?

    Directory of Open Access Journals (Sweden)

    Saddler Jack N

    2011-10-01

    Full Text Available Abstract Background We and other workers have shown that accessory enzymes, such as β-glucosidase, xylanase, and cellulase cofactors, such as GH61, can considerably enhance the hydrolysis effectiveness of cellulase cocktails when added to pretreated lignocellulosic substrates. It is generally acknowledged that, among the several factors that hamper our current ability to attain efficient lignocellulosic biomass conversion yields at low enzyme loadings, a major problem lies in our incomplete understanding of the cooperative action of the different enzymes acting on pretreated lignocellulosic substrates. Results The reported work assessed the interaction between cellulase and xylanase enzymes and their potential to improve the hydrolysis efficiency of various pretreated lignocellulosic substrates when added at low protein loadings. When xylanases were added to the minimum amount of cellulase enzymes required to achieve 70% cellulose hydrolysis of steam pretreated corn stover (SPCS, or used to partially replace the equivalent cellulase dose, both approaches resulted in enhanced enzymatic hydrolysis. However, the xylanase supplementation approach increased the total protein loading required to achieve significant improvements in hydrolysis (an additive effect, whereas the partial replacement of cellulases with xylanase resulted in similar improvements in hydrolysis without increasing enzyme loading (a synergistic effect. The enhancement resulting from xylanase-aided synergism was higher when enzymes were added simultaneously at the beginning of hydrolysis. This co-hydrolysis of the xylan also influenced the gross fiber characteristics (for example, fiber swelling resulting in increased accessibility of the cellulose to the cellulase enzymes. These apparent increases in accessibility enhanced the steam pretreated corn stover digestibility, resulting in three times faster cellulose and xylan hydrolysis, a seven-fold decrease in cellulase loading and

  10. 球毛壳菌60S核糖体蛋白L10a基因克隆与特性分析%Cloning and Characterization Analysis of 60S Ribosomal Protein L10a Gene from Chaetomium globosum

    Institute of Scientific and Technical Information of China (English)

    刘志华; 杨谦

    2006-01-01

    用粗糙脉孢菌(Neurospora crassa)XP_322380和赤霉菌(Gibberella zeae)PH-1(EAA76971)的60S核糖体蛋白L10a基因(60S ribosomal protein L10a,RPL10a)蛋白序列对球毛壳菌(Chaetomium globosum)ESTs序列数据库进行tBlastn检索,获得了球毛壳菌RPL10a cDNA序列.cDNA序列长765 bp,开放阅读框654 bp,编码217个氨基酸组成的多肽,蛋白分子量为23.9 kD.BlastP分析表明该基因氨基酸序列与粗糙脉胞菌相似最高为89%;与玉蜀黍黑粉菌(Ustilago maydis)相似性最低为78%.cDNA序列及推测的氨基酸序列在GenBank登录(登录号分别为AY669070,AAT74578).

  11. Enzymatic saccharification of sugar cane bagasse by continuous xylanase and cellulase production from cellulomonas flavigena PR-22.

    Science.gov (United States)

    Rojas-Rejón, Óscar A; Poggi-Varaldo, Héctor M; Ramos-Valdivia, Ana C; Ponce-Noyola, Teresa; Cristiani-Urbina, Eliseo; Martínez, Alfredo; de la Torre, Mayra

    2016-03-01

    Cellulase (CMCase) and xylanase enzyme production and saccharification of sugar cane bagasse were coupled into two stages and named enzyme production and sugar cane bagasse saccharification. The performance of Cellulomonas flavigena (Cf) PR-22 cultured in a bubble column reactor (BCR) was compared to that in a stirred tank reactor (STR). Cells cultured in the BCR presented higher yields and productivity of both CMCase and xylanase activities than those grown in the STR configuration. A continuous culture with Cf PR-22 was run in the BCR using 1% alkali-pretreated sugar cane bagasse and mineral media, at dilution rates ranging from 0.04 to 0.22 1/h. The highest enzymatic productivity values were found at 0.08 1/h with 1846.4 ± 126.4 and 101.6 ± 5.6 U/L·h for xylanase and CMCase, respectively. Effluent from the BCR in steady state was transferred to an enzymatic reactor operated in fed-batch mode with an initial load of 75 g of pretreated sugar cane bagasse; saccharification was then performed in an STR at 55°C and 300 rpm for 90 h. The constant addition of fresh enzyme as well as the increase in time of contact with the substrate increased the total soluble sugar concentration 83% compared to the value obtained in a batch enzymatic reactor. This advantageous strategy may be used for industrial enzyme pretreatment and saccharification of lignocellulosic wastes to be used in bioethanol and chemicals production from lignocellulose. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:321-326, 2016. PMID:26701152

  12. Heterologous Expression of Family 10 Xylanases from Acidothermus cellulolyticus Enhances the Exoproteome of Caldicellulosiruptor bescii and Growth on Xylan Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun-Ki; Chung, Daehwan; Himmel, Michael E.; Bomble, Yannick J.; Westpheling, Janet

    2016-08-22

    The ability to deconstruct plant biomass without conventional pretreatment has made members of the genus Caldicellulosiruptor the target of investigation for the consolidated processing of lignocellulosic biomass to biofuels and bioproducts. These Gram-positive bacteria are hyperthermophilic anaerobes and the most thermophilic cellulolytic organisms so far described. They use both C5 and C6 sugars simultaneously and have the ability to grow well on xylan, a major component of plant cell walls. This is an important advantage for their use to efficiently convert biomass at yields sufficient for an industrial process. For commodity chemicals, yield from substrate is perhaps the most important economic factor. In an attempt to improve even further the ability of C. bescii to use xylan, we introduced two xylanases from Acidothermus cellulolyticus. Acel_0180 includes tandem carbohydrate-binding modules (CBM2 and CBM3) located at the C-terminus, one of which, CBM2, is not present in C. bescii. Also, the sequences of Xyn10A and Acel_0180 have very little homology with the GH10 domains present in C. bescii. For these reasons, we selected these xylanases as potential candidates for synergistic interaction with those in the C. bescii exoproteome. Heterologous expression of two xylanases from Acidothermus cellulolyticus in Caldicellulosiruptor bescii resulted in a modest, but significant increase in the activity of the exoproteome of C. bescii on xylan substrates. Even though the increase in extracellular activity was modest, the ability of C. bescii to grow on these substrates was dramatically improved suggesting that the xylan substrate/microbe interaction substantially increased deconstruction over the secreted free enzymes alone. We anticipate that the ability to efficiently use xylan, a major component of plant cell walls for conversion of plant biomass to products of interest, will allow the conversion of renewable, sustainable, and inexpensive plant feedstocks to

  13. Cellulose and hemicellulose-degrading enzymes in Fusarium commune transcriptome and functional characterization of three identified xylanases.

    Science.gov (United States)

    Huang, Yuhong; Busk, Peter Kamp; Lange, Lene

    2015-06-01

    Specific enzymes from plant-pathogenic microbes demonstrate high effectiveness for natural lignocellulosic biomass degradation and utilization. The secreted lignocellulolytic enzymes of Fusarium species have not been investigated comprehensively, however. In this study we compared cellulose and hemicellulose-degrading enzymes of classical fungal enzyme producers with those of Fusarium species. The results indicated that Fusarium species are robust cellulose and hemicellulose degraders. Wheat bran, carboxymethylcellulose and xylan-based growth media induced a broad spectrum of lignocellulolytic enzymes in Fusarium commune. Prediction of the cellulose and hemicellulose-degrading enzymes in the F. commune transcriptome using peptide pattern recognition revealed 147 genes encoding glycoside hydrolases and six genes encoding lytic polysaccharide monooxygenases (AA9 and AA11), including all relevant cellulose decomposing enzymes (GH3, GH5, GH6, GH7, GH9, GH45 and AA9), and abundant hemicellulases. We further applied peptide pattern recognition to reveal nine and seven subfamilies of GH10 and GH11 family enzymes, respectively. The uncharacterized XYL10A, XYL10B and XYL11 enzymes of F. commune were classified, respectively, into GH10 subfamily 1, subfamily 3 and GH11 subfamily 1. These xylanases were successfully expressed in the PichiaPink™ system with the following properties: the purified recombinant XYL10A had interesting high specific activity; XYL10B was active at alkaline conditions with both endo-1,4-β-d-xylanase and β-xylosidase activities; and XYL11 was a true xylanase characterized by high substrate specificity. These results indicate that F. commune with genetic modification is a promising source of enzymes for the decomposition of lignocellulosic biomass.

  14. Conformation analysis of a surface loop that controls active site access in the GH11 xylanase A from Bacillus subtilis.

    Science.gov (United States)

    Vieira, Davi Serradella; Ward, Richard John

    2012-04-01

    Xylanases (EC 3.2.1.8 endo-1,4-glycosyl hydrolase) catalyze the hydrolysis of xylan, an abundant hemicellulose of plant cell walls. Access to the catalytic site of GH11 xylanases is regulated by movement of a short β-hairpin, the so-called thumb region, which can adopt open or closed conformations. A crystallographic study has shown that the D11F/R122D mutant of the GH11 xylanase A from Bacillus subtilis (BsXA) displays a stable "open" conformation, and here we report a molecular dynamics simulation study comparing this mutant with the native enzyme over a range of temperatures. The mutant open conformation was stable at 300 and 328 K, however it showed a transition to the closed state at 338 K. Analysis of dihedral angles identified thumb region residues Y113 and T123 as key hinge points which determine the open-closed transition at 338 K. Although the D11F/R122D mutations result in a reduction in local inter-intramolecular hydrogen bonding, the global energies of the open and closed conformations in the native enzyme are equivalent, suggesting that the two conformations are equally accessible. These results indicate that the thumb region shows a broader degree of energetically permissible conformations which regulate the access to the active site region. The R122D mutation contributes to the stability of the open conformation, but is not essential for thumb dynamics, i.e., the wild type enzyme can also adapt to the open conformation.

  15. Purification and characterization of a new xylanase (APX-II) from the fungus Aureobasidium pullulans Y-2311-1.

    OpenAIRE

    Li, X.L.; Z. Q. Zhang; Dean, J F; Eriksson, K E; Ljungdahl, L G

    1993-01-01

    Aureobasidium pullulans Y-2311-1 produced four major xylanases (EC 3.2.1.8) with pI values of 4.0, 7.3, 7.9, and 9.4 as revealed by isoelectric focusing and zymogram analysis when grown for 4 days on 1.0% oat spelt xylan. The enzyme with a pI of 9.4 was purified by ammonium sulfate precipitation, chromatography on a DEAE-Sephadex A-50 column, and gel filtration with a Sephadex G-75 column. The enzyme had a mass of about 25 kDa as determined by both sodium dodecyl sulfate-polyacrylamide gel el...

  16. Effect of temperature on the production of cellulases, xylanases and lytic enzymes by selected Trichoderma reesei mutants

    OpenAIRE

    Piotr Janas; Zdzisław Targoński

    2014-01-01

    The effect of temperature in the rangę of 26-38°C on the production of cellulases, xylanases and lytic enzymes by four mutant strains of Trichoderma reesei was analysed. On the basis of these investigations three thermosensitive strains (M-7. RUT C 30 and VTT-D-78085) which showed reduced excretion of the above mentioned enzymes as well as protein and a thermoresistant mutant (VTT-D-79I24) which grew within a temperature range of 26-34°C were characterized. Higher temperature caused an increa...

  17. A xylanase gene directly cloned from the genomic DNA of alkaline wastewater sludge showing application potential in the paper industry.

    Science.gov (United States)

    Zhao, Yanyu; Luo, Huiying; Meng, Kun; Shi, Pengjun; Wang, Guozeng; Yang, Peilong; Yuan, Tiezheng; Yao, Bin

    2011-09-01

    A xylanase gene, aws-2x, was directly cloned from the genomic DNA of the alkaline wastewater sludge using degenerated PCR and modified TAIL-PCR. The deduced amino acid sequence of AWS-2x shared the highest identity (60%) with the xylanase from Chryseobacterium gleum belonging to the glycosyl hydrolase GH family 10. Recombinant AWS-2x was expressed in Escherichia coli BL21 (DE3) and purified to electrophoretic homogeneity. The enzyme showed maximal activity at pH 7.5 and 55 °C, maintained more than 50% of maximal activity when assayed at pH 9.0, and was stable over a wide pH range from 4.0 to 11.0. The specific activity of AWS-2x towards hardwood xylan (beechwood and birchwood xylan) was significantly higher than that to cereal xylan (oat spelt xylan and wheat arabinoxylan). These properties make AWS-2x a potential candidate for application in the pulp and paper industry.

  18. Characterizing and improving the thermostability of purified xylanase from Aspergillus niger DFR-5 grown on solid-state-medium

    Directory of Open Access Journals (Sweden)

    Ajay Pal

    2010-12-01

    Full Text Available  The thermostability of absolutely purified xylanase from Aspergillus niger DFR-5 was improved using polyols. Supplementation of sorbitol at 2M concentration was found to increase the half-life and D-value of xylanase at elevated temperatures (45-70ºC. Thermodynamic parameters associated with the process were analyzed revealing that the stability at higher temperatures was due to the increased enthalpy (∆Hº and free energy (∆Gº change of enzyme denaturation in the presence of sorbitol. The negative values of ∆Sº (-150.093 Jmol-1K-1 at 70ºC clearly indicated that enzyme underwent a significant process of aggregation during denaturation. The enzyme required divalent cations for maximum activity and inhibited by chelator. The diminution of activity by various thiol-binding agents and enhancement by reducing agents like β-ME confirmed the essentiality of cysteine for catalysis. The enzyme had a half-life and D-value of 277 and 921 days when stored at 4 ºC.

  19. THE INFLUENCE OF ASOCIATED SUPPLEMENT OF ALFA AMYLASE AND XYLANASE ON THE RHEOLOGY OF DOUGH CONCEARNING ITS CONSTITOGRAPHICAL PARAMETERS

    Directory of Open Access Journals (Sweden)

    RODICA CHEREJI

    2013-07-01

    Full Text Available In this paper we determined the influence of associated supplement of alfa amylase and xylanase on the rheology of dough concearning its constitographical parameters : maximum pressure (Pr max, (mb and the absorbed water (Wa, %. The analysis on the consistograph were conducted for constant hydration at the consistency of 500 UF. Determinations were made on 4 types of flour and optimal dosages were found for each enzyme, after which we prepared the optimal dosage of the enzymes in the compund for flour F1 and F2 : P1-840000 U. SKB/100 kg flour +8100 U. FXU /100 kg flour, P2-840000 U. SKB/100 kg flour+16200 U. FXU, /100 kg flour , P3-840000 U. SKB/100 kg flour+24300 U. FXU/100 kg flour , and for F3 and F4 thus: P1-280000 U. SKB/100 kg flour +8100 U. FXU /100 kg flour, P2- 280000 U. SKB/100 kg flour+16200 U. FXU/100 kg flour, P3-280000 U. SKB/100 kg flour+24300 U. FXU/100 kg flour. Fungous α-amylase and xylanase were used in these concentrations to establish which one is more apropriate to be added in flour to obtain superior quality of bread: finer texture of the crumb, prolongation of the freashness of the bread, improvind the colour and flavour, emproving the slicing ability.

  20. Heterologous expression, purification, crystallization and preliminary X-ray analysis of Trichoderma reesei xylanase II and four variants

    International Nuclear Information System (INIS)

    The wild-type protein and four active-site mutants of xylanase II from Trichoderma reesei that catalyzes the hydrolysis of glycosidic bonds in xylan have successfully been crystallized. The crystallization of several structures including ligand-free and protein ligand complexes containing the substrate (xylohexaose) or product (xylotriose) are detailed. Xylanase II from Trichoderma reesei catalyzes the hydrolysis of glycosidic bonds in xylan. Crystallographic studies of this commercially important enzyme have been initiated to investigate its reaction mechanism, substrate binding and dependence on basic pH conditions. The wild-type protein was heterologously expressed in an Escherichia coli host using the defined medium and four active-site amino acids were replaced to abolish its activity (E177Q and E86Q) or to change its pH optimum (N44D and N44H). Cation-exchange and size-exclusion chromatography were used to obtain >90% protein purity. The ligand-free proteins and variant complexes containing substrate (xylohexaose) or product (xylotriose) were crystallized in several different space groups and diffracted to high resolutions (from 1.07 to 1.55 Å)

  1. Production, purification, and characterization of a cellulase-free thermostable endo-xylanase from Thermoanaerobacterium thermosaccharolyticum DSM 571.

    Science.gov (United States)

    Li, Xun; Shi, Hao; Ding, Huaihai; Zhang, Yu; Wang, Fei

    2014-12-01

    This is the first report describing the cloning, expression, and characterization of a putative thermostable, cellulase-free xylanase (XYN) from the thermophilic bacterium Thermoanaerobacterium thermosaccharolyticum DSM 571. The temperature and pH values for optimal enzyme activity of XYN were found to be 65 °C and pH 6.5, respectively. The XYN activity was apparently enhanced by Co(2+), Mn(2+), and Tween 60 and significantly inactivated by Al(3+), Cu(2+), Zn(2+), and SDS. The K m and V max values of XYN for the hydrolysis of beechwood xylan were 2.1 mg/ml and 222.1 U/mg, respectively. The k cat values of XYN for beechwood xylan at the optimal temperature and pH values were 481.4 s(-1). XYN represents an attractive candidate for use in the large-scale production of xylooligosaccharides (XOs) from forest residues because it is an endo-xylanase capable of degrading xylan. PMID:25261357

  2. Engineering the hydrophobic residues of a GH11 xylanase impacts its adsorption onto lignin and its thermostability.

    Science.gov (United States)

    Rakotoarivonina, Harivony; Hermant, Béatrice; Aubry, Nathalie; Rémond, Caroline

    2015-12-01

    This study aimed to characterise the parameters governing the non-specific adsorption of a xylanase from Thermobacillus xylanilyticus (Tx-Xyn11) onto lignin isolated from maize stems. Such adsorption may be due to hydrophobic interactions between Tx-Xyn11 and lignin. Our strategy was to mutate hydrophobic residues present on the surface of Tx- Xyn11 into non-hydrophobic residues. Three mutants (P1, P2, and P3) with altered hydrophobic regions were produced and characterised. The thermostability of the P1 mutant was largely decreased compared with the thermostable Tx-Xyn11. The rate of adsorbed enzyme onto lignin was reduced to a similar extent for the P1 and P2 mutants, whereas the adsorption of the P3 mutant was less affected compared with that of Tx-Xyn11. When considered separately, the hydrophobic residues did not affect xylanase adsorption onto lignin. The addition of Tween 20 also led to the decreased adsorption of Tx-Xyn11 onto lignin. These results suggest that hydrophobic interactions are a key parameter in the interaction of Tx-Xyn11 with isolated lignin.

  3. Generation of transgenic wheat (Triticum aestivum L.) accumulating heterologous endo-xylanase or ferulic acid esterase in the endosperm

    Energy Technology Data Exchange (ETDEWEB)

    Harholt, Jesper; Bach, Inga C; Lind-Bouquin, Solveig; Nunan, Kylie J.; Madrid, Susan M.; Brinch-Pedersen, Henrik; Holm, Preben B.; Scheller, Henrik V.

    2009-12-08

    Endo-xylanase (from Bacillus subtilis) or ferulic acid esterase (from Aspergillus niger) were expressed in wheat under the control of the endosperm specific 1DX5 glutenin promoter. Constructs both with and without the endoplasmic reticulum retention signal KDEL were used. Transgenic plants were recovered in all four cases but no qualitative differences could be observed whether KDEL was added or not. Endo-xylanase activity in transgenic grains was increased between two and three fold relative to wild type. The grains were shriveled and had a 25-33% decrease in mass. Extensive analysis of the cell walls showed a 10-15% increase in arabinose to xylose ratio, a 50% increase in the proportion of water extractable arabinoxylan, and a shift in the MW of the water extractable arabinoxylan from being mainly larger than 85 kD to being between 2 kD and 85 kD. Ferulic acid esterase expressing grains were also shriveled and the seed weight was decreased by 20-50%. No ferulic acid esterase activity could be detected in wild type grains whereas ferulic acid esterase activity was detected in transgenic lines. The grain cell walls had 15-40% increase in water unextractable arabinoxylan and a decrease in monomeric ferulic acid between 13 and 34%. In all the plants the observed changes are consistent with a plant response that serves to minimize the effect of the heterologously expressed enzymes by increasing arabinoxylan biosynthesis and cross-linking.

  4. Antioxidant capacity of arabinoxylan oligosaccharide fractions prepared from wheat aleurone using Trichoderma viride or Neocallimastix patriciarum xylanase.

    Science.gov (United States)

    Malunga, Lovemore Nkhata; Beta, Trust

    2015-01-15

    The effect of xylanase type (Trichoderma viride or Neocallimastix patriciarum) and graded ethanol fractionation on the antioxidant capacity (AOC) of arabinoxylan oligosaccharides (AXOS) obtained from wheat aleurone was investigated. AXOS yields were higher using N. patriciarum (62%) than T. viride (44%). The fraction (F100) collected at >80% ethanol concentration constituted 60% of total recovered AXOS. Degree of substitution ranged from 0.20 to 0.60 for ethanol graded fractions. Ferulic acid (FA) esterified to AXOS (8.0 μg/ mg) was 2-fold lower for the N. patriciarum treatment. The mean AOC (41.6, 183.1, and 394.9 μM TE/mg) of T. viride treated AXOS was >1.4-fold higher than N. patriciarum treatment using DPPH and ABTS and ORAC assays, respectively. Fraction F100 had highest AOC. AOC was influenced by the content of esterified FA (R(2)=0.94). The type of xylanase had a major influence on the AOC of the resultant AXOS rich in FA content.

  5. Effects of xylanase and citric acid on the performance, nutrient retention, and characteristics of gastrointestinal tract of broilers fed low-phosphorus wheat-based diets

    NARCIS (Netherlands)

    Esmaeilipour, O.; Shivazad, M.; Moravej, H.; Aminzadeh, S.; Rezaian, M.; Krimpen, van M.M.

    2011-01-01

    An experiment was conducted to study the effects of xylanase and citric acid on the performance, nutrient retention, jejunal viscosity, and size and pH of the gastrointestinal tract of broilers fed a low-P wheat-based diet. The experiment was conducted as a 2 × 3 factorial arrangement with 2 levels

  6. Effects of diet acidification and xylanase supplementation on performance, nutrient digestibility, duodenal histology and gut microflora of broilers fed wheat based diet

    NARCIS (Netherlands)

    Esmaeilipour, O.; Moravej, H.; Shivazad, M.; Rezaian, M.; Aminzadeh, S.; Krimpen, van M.M.

    2012-01-01

    1. The objective of this experiment was to study the influences of xylanase and citric acid on the performance, nutrient digestibility, digesta viscosity, duodenal histology, and gut microflora of broilers fed on a wheat based diet. 2. The experiment was carried out as a 2 x 3 factorial arrangement

  7. A new chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica affects Soybean Asian rust (Phakopsora pachyrhizi spore germination

    Directory of Open Access Journals (Sweden)

    Mehta Angela

    2011-02-01

    Full Text Available Abstract Background Asian rust (Phakopsora pachyrhizi is a common disease in Brazilian soybean fields and it is difficult to control. To identify a biochemical candidate with potential to combat this disease, a new chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica (CaclXIP leaves was cloned into the pGAPZα-B vector for expression in Pichia pastoris. Results A cDNA encoding a chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica (CaclXIP, was isolated from leaves. The amino acid sequence predicts a (β/α8 topology common to Class III Chitinases (glycoside hydrolase family 18 proteins; GH18, and shares similarity with other GH18 members, although it lacks the glutamic acid residue essential for catalysis, which is replaced by glutamine. CaclXIP was expressed as a recombinant protein in Pichia pastoris. Enzymatic assay showed that purified recombinant CaclXIP had only residual chitinolytic activity. However, it inhibited xylanases from Acrophialophora nainiana by approx. 60% when present at 12:1 (w/w enzyme:inhibitor ratio. Additionally, CaclXIP at 1.5 μg/μL inhibited the germination of spores of Phakopsora pachyrhizi by 45%. Conclusions Our data suggests that CaclXIP belongs to a class of naturally inactive chitinases that have evolved to act in plant cell defence as xylanase inhibitors. Its role on inhibiting germination of fungal spores makes it an eligible candidate gene for the control of Asian rust.

  8. Efficacy of xylanase purified from Aspergillus niger DFR-5 alone and in combination with pectinase and cellulase to improve yield and clarity of pineapple juice.

    Science.gov (United States)

    Pal, Ajay; Khanum, Farhath

    2011-10-01

    Pineapple is one of the fruits having xylan rich hemicellulose content more than pectin. Therefore, the efficacy of absolutely purified xylanase from A. niger DFR-5 alone and in combination with pectinase and cellulase on juice yield and clarity was studied. Xylanase provided maximum yield (71.3%) and clarity (64.7%) of juice in comparison to control responses (61.8% yield and 57.8% clarity). When used together, a synergistic effect of xylanase, pectinase and cellulase on process responses was observed indicating the necessity of a cock-tail of hydrolytic enzymes for complete cell wall degradation. Overall, an increase in juice yield by 52.9% was observed. The process was numerically optimized with the constraint of 'minimum' pectinase and cellulase and 'maximum' xylanase and incubation time for 'maximum' juice yield and clarity. The closeness of observed response (90.2% yield and 80.9% clarity) to the predicted one (89.6% yield and 80.3% clarity) indicated the validity of developed model. PMID:23572788

  9. Production of thermo-alkali-stable xylanase by a novel polyextremophilic Bacillus halodurans TSEV1 in cane molasses medium and its applicability in making whole wheat bread.

    Science.gov (United States)

    Kumar, Vikash; Satyanarayana, T

    2014-06-01

    A high titre of thermo-alkali-stable xylanase was attained in cane molasses medium. When the culture variables for endoxylanase production were optimized [cane molasses 7 %, soluble alkaline extract of wheat bran (SAE-WB) 37 % and ammonium chloride 0.30 %], a 4.5-fold enhancement in xylanase production (69 U ml(-1)) was achieved as compared to that in the unoptimized medium (15 U ml(-1)). The enzyme titre attained in shake flasks could be sustained in a 7-l laboratory bioreactor. An activity band corresponding to 40 kDa was visualized on SDS-PAGE zymogram analysis. The enzyme has broad range of pH and temperature for activity with optima at 9.0 and 80 °C, and stable between pH 4.0 and 11.0 with 85 % retention of activity. It has T 1/2 of 40 and 15 min at 70 and 80 °C. The enzyme is halotolerant since it displays activity in the presence of salt up to 15 %, and remains 100 % active in the absence of salt. The supplementation of whole wheat dough with xylanase improves antistaling property, reducing sugar content, bread volume with prebiotic xylooligosaccharides in bread. This is the first report on xylanase production in cane molasses medium with SAE-WB as the inducer and its applicability in whole wheat bread making that improves human health. PMID:24297158

  10. The effective expression of xylanase gene in Candida utilis by 18S rDNA targeted homologous recombination in pGLR9K.

    Science.gov (United States)

    Wei, Wang; Hong-Lan, Yang; HuiFang, Bao; Daoyuan, Zhang; Qi-mu-ge, Shan; Woof, Andrew J

    2010-07-01

    In order to test whether 18S rDNA can influence positively xylanase gene effective expression in the yeast of Candida utilis, a targeting vector pGLR9K-XA was constructed by adding an interested gene xynA from Streptomyces olivaceoviridis into the vector pGLR9K which is constructed by ourselves. pGLR9K contains the 18S rDNA, GAP promoter and CYH resistance gene sequence, all of which is from C. utilis. Then the vector pGLR9K-XA was transformed into C. utilis. To test the vector and transformed system, PCR, Southern blot and DNS methods were used. The results showed that xylanase gene can be detected in the chromosome DNA of recombinant C. utilis and the enzyme activity of xylanase is up to 60 IU ml(-1) in the study. It is suggested that this system can be used to express exogenous genes in C. utilis as a bioreactors. This is the first report that xylanase gene was expressed in C. utilis. PMID:19731075

  11. Preparation, Purification, and Secondary Structure Determination of Bacillus Circulans Xylanase. A Molecular Laboratory Incorporating Aspects of Molecular Biology, Biochemistry, and Biophysical Chemistry

    Science.gov (United States)

    Russo, Sal; Gentile, Lisa

    2006-01-01

    A project module designed for biochemistry or cellular and molecular biology student which involves determining the secondary structure of Bacillus circulans xylanase (BCX) by circular dichroism (CD) spectroscopy under conditions that compromise its stabilizing intramolecular forces is described. The lab model enhanced students knowledge of the…

  12. Biochemical and Thermodynamic Characterization of a Novel, Low Molecular Weight Xylanase from Bacillus Methylotrophicus CSB40 Isolated from Traditional Korean Food.

    Science.gov (United States)

    Panthi, Sandesh; Choi, Yoon Seok; Choi, Yun Hee; Kim, MiRi; Yoo, Jin Cheol

    2016-04-01

    A low molecular weight xylanase from Bacillus strain CSB40, isolated from traditional Korean food and produced in beechwood xylan, was biochemically and thermodynamically characterized. It was purified 8.12-fold with a 15.88 % yield using DEAE sepharose fast flow, and it was determined to have a mass of ∼27 kDa via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and xylan zymography. The purified xylanase was optimally active at 50 °C and pH 6 and stable over a wide range of pH (4.5-12.5). The N-terminal amino acid sequence of xylanase was GIQQGDDGKL. The activation energy for beechwood xylan hydrolysis was 29.39 kJmol(-1) with k cat value of 927.582 × 10(2) s(-1). K m and V max were 0.080 mg/ml and 794.63 mmol min(-1) mg(-1). The analysis of other thermodynamic parameters like ∆H, ∆G, ∆S, Q10, ∆GE-S, and ∆GE-T also supported the spontaneous formation of products, greater hydrolytic efficiency, and feasibility of enzymatic reaction, which also ratifies the novelty of this xylanase. The enzyme was strongly activated by Zn(2+) and inhibited by Cu(2+). The principal hydrolyzed end-products of this xylanase are xylobiose, xylotriose, and xylotetrose, which can be used in the pharmaceutical industry and as prebiotic in food. PMID:26780766

  13. Cloning of a novel xylanase gene from a newly isolated Fusarium sp. Q7-31 and its expression in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Zhan-Ling Xie

    2012-03-01

    Full Text Available A strain of Q7-31 was isolated from Qinghai-Tibet Plateau and was identified as Fusarium sp. based on its morphological characteristics and ITS rDNA gene sequence analysis. It has the highest capacity of degrading cell wall activity compared with other 11 strains. To do research on its xylanase activity of Fusarium sp. Q7-31 while the degrading the rice cell walls, the complete gene xyn8 that encodes endo-1, 4-β-xylanase secreted by Fusarium sp. Q7-31 was cloned and sequenced. The coding region of the gene is separated by two introns of 56bp and 55bp. It encodes 230 amino acid residues of a protein with a calculated molecular weight of 25.7 kDa. The animo acids sequence of xyn8 gene has higher similarity with those of family 11 of glycosyl hydrolases reported from other microorganisms. The nature peptide encodeing cDNA was subcloned into pGEX5x-1 expression vector. The recombinant plasmid was expressed in Escherichia coli BL21-CodonPlus (DE3-RIL, and xylanase activity was measured. The expression fusion protein was identified by SDS-PAGE and Western blotting, a new specific band of about 52kDa was identified when induced by IPTG. Enzyme activity assay verified the recombinants proteins as a xylanase. A maxium activity of 2.34U/ mg, the xylanase had optimal activity at pH 6.0 and temperature 40ºC .

  14. Improved Enzyme Catalytic Characteristics upon Glutaraldehyde Cross-Linking of Alginate Entrapped Xylanase Isolated from Aspergillus flavus MTCC 9390

    Science.gov (United States)

    Bhushan, Bharat; Pal, Ajay; Jain, Veena

    2015-01-01

    Purified fungal xylanase was entrapped in alginate beads. Its further cross-linking using glutaraldehyde resulted in large enzyme aggregates which may function as both a catalyst and a support material for numerous substrate molecules. Enzyme cross-linking presented a negative impact on enzyme leaching during repeated washings and recovery of enzyme activity was substantial after twelve cycles of usage. The entrapment followed by cross-linking doubled the total bound activity and also greatly improved the enzyme stability at extreme chemical environment. The wide pH stability, better thermo- and storage stability, lowered Km value, and protection from some metal ions are salient achievements of present immobilization. The study shows the efficacy, durability, and sustainability of immobilized catalytic system which could be efficiently used for various juice processing operations. PMID:26347814

  15. Xylanase production with xylan rich lignocellulosic wastes by a local soil isolate of Trichoderma viride Produção de xilanase com resíduos lignocelulósicos ricos em xilana por uma cepa local de Trichoderma viride isolada de solo

    OpenAIRE

    Meenakshi Goyal; Kalra, K. L.; V.K. Sareen; G. Soni

    2008-01-01

    In the present study, cultural and nutritional conditions for enhanced production of xylanase by a local soil isolate of Trichoderma viride, using various lignocellulosic substrates in submerged culture fermentation have been optimized. Of the lignocellulosics used, maize straw was the best inducer followed by jowar straw for xylanase production. The highest activity achieved was between 14 to 17 days of fermentation. A continuous increase in xylanase production was observed with increasing l...

  16. Production and Accumulation of Xylooligosaccharides with Long Chains by Growing Culture and Xylanase of a Mutant Strain of Bacillus pumilus X-6-19

    Institute of Scientific and Technical Information of China (English)

    Qingzhu Yuan; Tsuyoshi Adachi; Shinji Takenaka; Shuichiro Murakami; Machiko Tanaka; Kenji Aoki

    2008-01-01

    Bacillus pumilus X-6-9 isolated from soil and subsequently identified, produced xylooligosacchatides with long chainsfrom xylan and accumulated them in the culture. By improving the culture conditions and mutating the bacterium, a 3.2-fold increasein the production of the xylooligosaccharides was established, when compared to the original culture conditions of B. pumilus X-6-19.The addition of D-glucose to the culture of the mutant swain U-3 of B. pumilus X-6-9 repressed the synthesis of β-xylosidase, but notxylanase. Thus, it was revealed that strain U-3 was a good organism for the production and accumulation of xylooligosaccharideswith long chains from xylan by a microbial culture. Xylanase produced by strain U-3 was purified to homogeneity and characterized.The hydrolyzates generated by the purified xylanase contained xylobiose, xylotrinse, xylotewaose, and xylopentaose, but not xylose.

  17. The N-terminal cellulose-binding domain of EGXA increases thermal stability of xylanase and changes its specific activities on different substrates

    Institute of Scientific and Technical Information of China (English)

    Ming Ding; Yigang Teng; Qiuyu Yin; Jie Zhao; Fukun Zhao

    2008-01-01

    A full-length EGXA enzyme from a mollusk, Ampullaria crossean, was cloned into pFastBac vector and then heterogeneously expressed in insect Tn5 cells. Its natural N-terminal signal peptide worked well in the insect Tn5 cells.The recombinant EGXA was a 63 kDa protein and had active endo-β-1,4-glucanase (EC 3.2.1.4) and endo-β-1,4-xylanase (EC 3.2.1.8). The specific activity of endo-β-1,4-xylanase was higher than in the EGX, which was purified from the stomach tissues of Ampullaria crossen. The N-terminal cellulosebinding domain of EGXA made it bind to cellulose and xylan more efficiently. This cellulose-binding domain also increased the thermal stability of this recombinant enzyme and decreased the recombinant EGXA's specific activities on p-nitrophenyi-β-D-cellobioside and sodium carboxymethyl cellulose.

  18. Xylanase Increased the Ileal Digestibility of Non-Starch Polysaccharides and Concentration of Low Molecular Weight Non-Digestible Carbohydrates in Pigs Fed High Levels of wheat DDGS

    DEFF Research Database (Denmark)

    Pedersen, Mads Brøgger; Yu, Shukun; Arent, Susan;

    2015-01-01

    polysaccharides (NSP), low molecular weight (LMW) NDC, OM, CP, fat, starch, and marker. Compared with the control diet, addition of CAX, EX, and EXP increased the AID of arabinoxylan by 32 (P ...The objective was to study the effect of a commercially available xylanase (CAX), an experimental xylanase (EX), and EX in combination with protease (EXP) on the degradation of nondigestible carbohydrates (NDC) and apparent ileal digestibility (AID) of nutrients in wheat distillers dried grains...... with solubles (wDDGS). The control and 3 enzyme diets contained 96% wDDGS supplemented with vitamins, minerals, l-lysine, and chromic oxide as a digestibility marker in addition to enzyme premix. Eight ileal cannulated pigs were fed 4 experimental diets containing 96% wDDGS—a control diet or 1 of 3 diets...

  19. Individual and combined effects of water addition with xylanases and laccase on the loaf quality of composite wheat–cassava bread

    DEFF Research Database (Denmark)

    Serventi, Luca; Skibsted, Leif Horsfelt; Kidmose, Ulla

    2016-01-01

    The objective was to study how water addition and addition of enzymes like xylanases and a laccase will improve the loaf quality of composite wheat–cassava bread. The loaf quality was determined by sensory profiling, volume measurement and texture profile analysis. High intensity of sensory...... hardness was measured at 58 % water addition, likely due to insufficient plasticization of the gluten–starch network, while hardening and crumb structure collapse were observed at 76 % water addition. Enzyme evaluation revealed higher pore size upon treatment with the xylanase Panzea® BG (Panzea) compared...... of polyphenols and/or arabinoxylans. In confirmation to these findings, the combination of high water addition (70 %) and Panzea treatment generated larger and better structured bread....

  20. Effect of β-glucanase and xylanase supplementation of barley- and rye-based diets on caecal microbiota of broiler chickens

    DEFF Research Database (Denmark)

    Josefiak, Damian; Rutkowski, A; Kaczmarek, S;

    2010-01-01

    1. The aim was to investigate the effect of grain type (barley or rye) and exogenous enzymes (β-glucanase or xylanase) on the composition of chicken caecal microbiota as examined by classical culturing and molecular techniques (fluorescent in-situ hybridisation (FISH) and terminal-restriction fra......1. The aim was to investigate the effect of grain type (barley or rye) and exogenous enzymes (β-glucanase or xylanase) on the composition of chicken caecal microbiota as examined by classical culturing and molecular techniques (fluorescent in-situ hybridisation (FISH) and terminal......-restriction fragment-length polymorphism (T-RFLP)). 2. Plate counting revealed higher total numbers of anaerobic bacteria, lactic acid bacteria and yeasts in caecal contents of birds fed with rye-based diets than in birds fed with barley-based diets. 3. As assessed by FISH analysis, the most abundant bacterial groups...

  1. Control on the Wheat Non-Starch Polysaccharides (NSP)’ Anti-Nutritional Effect on Intestinal Wall, by Introducing Xylanase in Broiler Feed

    OpenAIRE

    Gabi Dumitrescu; Lavinia Ştef; Dan Drinceanu; Calin Julean; Ducu Stef; Liliana Petculescu Ciochina; Cosmin Pandur

    2011-01-01

    The experiment was performed in order to determine the protocol of xylanase utilization to fight against the antinutritional effect exerted by wheat non-starch polysaccharides (NSP) on intestinal wall in broilers. The experimental works were carried out on broilers, the hybrid Ross 308. We formed four experimental groups, as follows: the experimental group LE1, fed on forage without wheat in its structure, the experimental group LE2, fed on combined forage including wheat in a proportion of 4...

  2. 木聚糖酶对全麦粉品质的影响研究%EFFECTS OF XYLANASE ON THE QUALITY OF WHOLE WHEAT FLOUR

    Institute of Scientific and Technical Information of China (English)

    张成龙; 郑学玲; 刘翀

    2013-01-01

    研究了木聚糖酶对全麦粉基本理化指标、流变学特性及烘焙品质的影响.结果表明,随着木聚糖酶量的增加,全麦粉面团吸水率先升高后降低,形成时间先增加后减小,稳定时间降低,拉伸曲线面积和拉伸阻力均先减后增;经过木聚糖酶处理后,全麦面包的比容增大,硬度、黏着性和咀嚼性都降低.木聚糖酶添加量为0.1%时,全麦粉的品质有较好的改良效果.%We studied the effects of xylanase on the basic physicochemical indexes,rheological properties and baking qualities of whole wheat flour.The results showed that,as the addition amount of xylanase increased,the water absorption rate of the whole wheat flour dough decreased after increasing,the formation time was shortened after increasing,the settlement time was shortened,and both the tensile curve area and the tensile resistance increased after decreasing; the specific volume of whole wheat bread increased,and the hardness,adhesiveness and chewiness decreased after treatment with xylanase; and better improvement effect on the quality of the whole wheat flour was obtained when 0.1% xylanase was added.

  3. Control on the Wheat Non-Starch Polysaccharides (NSP’ Anti-Nutritional Effect on Intestinal Wall, by Introducing Xylanase in Broiler Feed

    Directory of Open Access Journals (Sweden)

    Gabi Dumitrescu

    2011-10-01

    Full Text Available The experiment was performed in order to determine the protocol of xylanase utilization to fight against the antinutritional effect exerted by wheat non-starch polysaccharides (NSP on intestinal wall in broilers. The experimental works were carried out on broilers, the hybrid Ross 308. We formed four experimental groups, as follows: the experimental group LE1, fed on forage without wheat in its structure, the experimental group LE2, fed on combined forage including wheat in a proportion of 40%, the experimental group LE3 including wheat in a proportion of 40% and xylanase, in an amount of 25 g / to, and the experimental group LE4, including wheat in a proportion of 40% and xylanase, in an amount of 100 g. At 3 and 6 weeks, successive to chicken killing, we sampled the intestinal wall and determined the main changes occurred. The histo-morpho-metric analysis of the four experimental groups led to the conclusions that: wheat administration in a proportion of 40% in the individuals in LE2 determines the development of vilositary muscle elements, decreased of intestinal villosities height, leucocitary migration, and also vascular ectasies and reduced hemorrhagic areas; xylanase addition in the wheat-based feed may be associated with the increase of intestinal villosities height, and especially at jejuna level the villosities seem slightly branched, a slight hypertrophy of the epithelial cells compared with the individuals in LE2, the increase of goblet cells frequency and hypertrophy of the capillary network. These microscopic aspects come together with more intens digestion and absorption processes, and especially in the experimental group 4.

  4. Optimization of β-Glucosidase, β-Xylosidase and Xylanase Production by Colletotrichum graminicola under Solid-State Fermentation and Application in Raw Sugarcane Trash Saccharification

    Directory of Open Access Journals (Sweden)

    Ana L. R. L. Zimbardi

    2013-01-01

    Full Text Available Efficient, low-cost enzymatic hydrolysis of lignocellulosic residues is essential for cost-effective production of bioethanol. The production of β-glucosidase, β-xylosidase and xylanase by Colletotrichum graminicola was optimized using Response Surface Methodology (RSM. Maximal production occurred in wheat bran. Sugarcane trash, peanut hulls and corncob enhanced β-glucosidase, β-xylosidase and xylanase production, respectively. Maximal levels after optimization reached 159.3 ± 12.7 U g−1, 128.1 ± 6.4 U g−1 and 378.1 ± 23.3 U g−1, respectively, but the enzymes were produced simultaneously at good levels under culture conditions optimized for each one of them. Optima of pH and temperature were 5.0 and 65 °C for the three enzymes, which maintained full activity for 72 h at 50 °C and for 120 min at 60 °C (β-glucosidase or 65 °C (β-xylosidase and xylanase. Mixed with Trichoderma reesei cellulases, C. graminicola crude extract hydrolyzed raw sugarcane trash with glucose yield of 33.1% after 48 h, demonstrating good potential to compose efficient cocktails for lignocellulosic materials hydrolysis.

  5. Supplementation with xylanase and β-xylosidase to reduce xylo-oligomer and xylan inhibition of enzymatic hydrolysis of cellulose and pretreated corn stover

    Directory of Open Access Journals (Sweden)

    Qing Qing

    2011-06-01

    Full Text Available Abstract Background Hemicellulose is often credited with being one of the important physical barriers to enzymatic hydrolysis of cellulose, and acts by blocking enzyme access to the cellulose surface. In addition, our recent research has suggested that hemicelluloses, particularly in the form of xylan and its oligomers, can more strongly inhibit cellulase activity than do glucose and cellobiose. Removal of hemicelluloses or elimination of their negative effects can therefore become especially pivotal to achieving higher cellulose conversion with lower enzyme doses. Results In this study, cellulase was supplemented with xylanase and β-xylosidase to boost conversion of both cellulose and hemicellulose in pretreated biomass through conversion of xylan and xylo-oligomers to the less inhibitory xylose. Although addition of xylanase and β-xylosidase did not necessarily enhance Avicel hydrolysis, glucan conversions increased by 27% and 8% for corn stover pretreated with ammonia fiber expansion (AFEX and dilute acid, respectively. In addition, adding hemicellulase several hours before adding cellulase was more beneficial than later addition, possibly as a result of a higher adsorption affinity of cellulase and xylanase to xylan than glucan. Conclusions This key finding elucidates a possible mechanism for cellulase inhibition by xylan and xylo-oligomers and emphasizes the need to optimize the enzyme formulation for each pretreated substrate. More research is needed to identify advanced enzyme systems designed to hydrolyze different substrates with maximum overall enzyme efficacy.

  6. Robust expression and secretion of Xylanase1 in Chlamydomonas reinhardtii by fusion to a selection gene and processing with the FMDV 2A peptide.

    Directory of Open Access Journals (Sweden)

    Beth A Rasala

    Full Text Available Microalgae have recently received attention as a potential low-cost host for the production of recombinant proteins and novel metabolites. However, a major obstacle to the development of algae as an industrial platform has been the poor expression of heterologous genes from the nuclear genome. Here we describe a nuclear expression strategy using the foot-and-mouth-disease-virus 2A self-cleavage peptide to transcriptionally fuse heterologous gene expression to antibiotic resistance in Chlamydomonas reinhardtii. We demonstrate that strains transformed with ble-2A-GFP are zeocin-resistant and accumulate high levels of GFP that is properly 'cleaved' at the FMDV 2A peptide resulting in monomeric, cytosolic GFP that is easily detectable by in-gel fluorescence analysis or fluorescent microscopy. Furthermore, we used our ble2A nuclear expression vector to engineer the heterologous expression of the industrial enzyme, xylanase. We demonstrate that linking xyn1 expression to ble2A expression on the same open reading frame led to a dramatic (~100-fold increase in xylanase activity in cells lysates compared to the unlinked construct. Finally, by inserting an endogenous secretion signal between the ble2A and xyn1 coding regions, we were able to target monomeric xylanase for secretion. The novel microalgae nuclear expression strategy described here enables the selection of transgenic lines that are efficiently expressing the heterologous gene-of-interest and should prove valuable for basic research as well as algal biotechnology.

  7. Robust expression and secretion of Xylanase1 in Chlamydomonas reinhardtii by fusion to a selection gene and processing with the FMDV 2A peptide.

    Science.gov (United States)

    Rasala, Beth A; Lee, Philip A; Shen, Zhouxin; Briggs, Steven P; Mendez, Michael; Mayfield, Stephen P

    2012-01-01

    Microalgae have recently received attention as a potential low-cost host for the production of recombinant proteins and novel metabolites. However, a major obstacle to the development of algae as an industrial platform has been the poor expression of heterologous genes from the nuclear genome. Here we describe a nuclear expression strategy using the foot-and-mouth-disease-virus 2A self-cleavage peptide to transcriptionally fuse heterologous gene expression to antibiotic resistance in Chlamydomonas reinhardtii. We demonstrate that strains transformed with ble-2A-GFP are zeocin-resistant and accumulate high levels of GFP that is properly 'cleaved' at the FMDV 2A peptide resulting in monomeric, cytosolic GFP that is easily detectable by in-gel fluorescence analysis or fluorescent microscopy. Furthermore, we used our ble2A nuclear expression vector to engineer the heterologous expression of the industrial enzyme, xylanase. We demonstrate that linking xyn1 expression to ble2A expression on the same open reading frame led to a dramatic (~100-fold) increase in xylanase activity in cells lysates compared to the unlinked construct. Finally, by inserting an endogenous secretion signal between the ble2A and xyn1 coding regions, we were able to target monomeric xylanase for secretion. The novel microalgae nuclear expression strategy described here enables the selection of transgenic lines that are efficiently expressing the heterologous gene-of-interest and should prove valuable for basic research as well as algal biotechnology. PMID:22937037

  8. GH10 XynA is the main xylanase identified in the crude enzymatic extract of Paenibacillus sp. A59 when grown on xylan or lignocellulosic biomass.

    Science.gov (United States)

    Ghio, Silvina; Insani, Ester M; Piccinni, Florencia E; Talia, Paola M; Grasso, Daniel H; Campos, Eleonora

    2016-01-01

    A novel bacterial isolate with polysaccharides degrading activity was identified as Paenibacillus sp., and named Paenibacillus sp. A59. Even though it is a strict mesophile, optimal xylanase activity of the crude enzymatic extract was achieved between 50°C and 70°C and more than 60% of the activity was retained after incubation for 48h at 50°C, indicating thermotolerance of the enzymes involved. The extract was also active on pre-treated sugarcane residue (SCR) and wheat straw, releasing xylobiose and xylose as the main products, therefore confirming its predominantly xylanolytic activity. By zymograms and mass spectrometry of crude enzymatic extracts of xylan or SCR cultures, a 32kDa GH10 beta- 1,4- endoxylanase with xylanase and no CMCase activity was identified. We named this enzyme XynA and it was the only xylanase identified under both conditions assayed, suggesting that it is a good candidate for recombinant expression and evaluation in hemicelluloses deconstruction applications. Also, a protein with two S-layer homology domains (SLH) and a large uncharacterized C-terminal domain as well as an ABC substrate binding protein were identified in crude extracts of SCR cultures. We propose that Paenibacillus sp. A59 uses a system similar to anaerobic and other Gram positive bacteria, with SLH-domain proteins anchoring polysaccharide-degrading enzymes close to the membrane and the substrate binding protein assisting translocation of simple sugars to the cell interior. PMID:27242139

  9. C-Terminal proline-rich sequence broadens the optimal temperature and pH ranges of recombinant xylanase from Geobacillus thermodenitrificans C5.

    Science.gov (United States)

    Irfan, Muhammad; Guler, Halil Ibrahim; Ozer, Aysegul; Sapmaz, Merve Tuncel; Belduz, Ali Osman; Hasan, Fariha; Shah, Aamer Ali

    2016-09-01

    Efficient utilization of hemicellulose entails high catalytic capacity containing xylanases. In this study, proline rich sequence was fused together with a C-terminal of xylanase gene from Geobacillus thermodenitrificans C5 and designated as GthC5ProXyl. Both GthC5Xyl and GthC5ProXyl were expressed in Escherichia coli BL21 host in order to determine effect of this modification. The C-terminal oligopeptide had noteworthy effects and instantaneously extended the optimal temperature and pH ranges and progressed the specific activity of GthC5Xyl. Compared with GthC5Xyl, GthC5ProXyl revealed improved specific activity, a higher temperature (70°C versus 60°C) and pH (8 versus 6) optimum, with broad ranges of temperature and pH (60-80°C and 6.0-9.0 versus 40-60°C and 5.0-8.0, respectively). The modified enzyme retained more than 80% activity after incubating in xylan for 3h at 80°C as compared to wild -type with only 45% residual activity. Our study demonstrated that proper introduction of proline residues on C-terminal surface of xylanase family might be very effective in improvement of enzyme thermostability. Moreover, this study reveals an engineering strategy to improve the catalytic performance of enzymes. PMID:27444327

  10. Cloning and expression of the xynA1 gene encoding a xylanase of the GH10 group in Caulobacter crescentus.

    Science.gov (United States)

    Graciano, Luciana; Corrêa, Juliana Moço; Vieira, Fabíola Giovanna Nesello; Bosetto, Adilson; Loth, Eduardo Alexandre; Kadowaki, Marina Kimiko; Gandra, Rinaldo Ferreira; Simão, Rita de Cássia Garcia

    2015-04-01

    Caulobacter crescentus (NA1000 strain) are aquatic bacteria that can live in environments of low nutritional quality and present numerous genes that encode enzymes involved in plant cell wall deconstruction, including five genes for β-xylosidases (xynB1-xynB5) and three genes for xylanases (xynA1-xynA3). The overall activity of xylanases in the presence of different agro-industrial residues was evaluated, and it was found that the residues from the processing of corn were the most efficient in inducing bacterial xylanases. The xynA1 gene (CCNA_02894) encoding a predicted xylanase of group 10 of glyco-hydrolases (GH10) that was efficiently overexpressed in Escherichia coli LMG194 using 0.02 % arabinose, after cloning into the vector pJet1.2blunt and subcloning into the expression vector pBAD/gIII, provided a fusion protein that contained carboxy-terminal His-tags, named XynA1. The characterization of pure XynA1 showed an enzymatic activity of 18.26 U mL(-1) and a specific activity of 2.22 U mg-(1) in the presence of xylan from beechwood as a substrate. XynA1 activity was inhibited by EDTA and metal ions such as Cu(2+) and Mg(2+). By contrast, β-mercaptoethanol, dithiothreitol (DTT), and Ca(2+) induced recombinant enzyme activity. Kinetic data for XynA1 revealed K M and V max values of 3.77 mg mL-(1) and 10.20 μM min-(1), respectively. Finally, the enzyme presented an optimum pH of 6 and an optimum temperature of 50 °C. In addition, 80 % of the activity of XynA1 was maintained at 50 °C for 4 h of incubation, suggesting a thermal stability for the biotechnological processes. This work is the first study concerning the cloning, overexpression, and enzymatic characterization of C. crescentus xylanase. PMID:25791579

  11. Cloning and expression of the xynA1 gene encoding a xylanase of the GH10 group in Caulobacter crescentus.

    Science.gov (United States)

    Graciano, Luciana; Corrêa, Juliana Moço; Vieira, Fabíola Giovanna Nesello; Bosetto, Adilson; Loth, Eduardo Alexandre; Kadowaki, Marina Kimiko; Gandra, Rinaldo Ferreira; Simão, Rita de Cássia Garcia

    2015-04-01

    Caulobacter crescentus (NA1000 strain) are aquatic bacteria that can live in environments of low nutritional quality and present numerous genes that encode enzymes involved in plant cell wall deconstruction, including five genes for β-xylosidases (xynB1-xynB5) and three genes for xylanases (xynA1-xynA3). The overall activity of xylanases in the presence of different agro-industrial residues was evaluated, and it was found that the residues from the processing of corn were the most efficient in inducing bacterial xylanases. The xynA1 gene (CCNA_02894) encoding a predicted xylanase of group 10 of glyco-hydrolases (GH10) that was efficiently overexpressed in Escherichia coli LMG194 using 0.02 % arabinose, after cloning into the vector pJet1.2blunt and subcloning into the expression vector pBAD/gIII, provided a fusion protein that contained carboxy-terminal His-tags, named XynA1. The characterization of pure XynA1 showed an enzymatic activity of 18.26 U mL(-1) and a specific activity of 2.22 U mg-(1) in the presence of xylan from beechwood as a substrate. XynA1 activity was inhibited by EDTA and metal ions such as Cu(2+) and Mg(2+). By contrast, β-mercaptoethanol, dithiothreitol (DTT), and Ca(2+) induced recombinant enzyme activity. Kinetic data for XynA1 revealed K M and V max values of 3.77 mg mL-(1) and 10.20 μM min-(1), respectively. Finally, the enzyme presented an optimum pH of 6 and an optimum temperature of 50 °C. In addition, 80 % of the activity of XynA1 was maintained at 50 °C for 4 h of incubation, suggesting a thermal stability for the biotechnological processes. This work is the first study concerning the cloning, overexpression, and enzymatic characterization of C. crescentus xylanase.

  12. Partial purification and properties of cellulase-free alkaline xylanase produced by Rhizopus stolonifer in solid-state fermentation

    Directory of Open Access Journals (Sweden)

    Antonio José Goulart

    2005-05-01

    Full Text Available Rhizopus stolonifer was cultivated in wheat bran to produce a cellulase-free alkaline xylanase. The purified enzyme obtained after molecular exclusion chromatography in Sephacryl S-200 HR showed optimum temperature as 45º C and hydrolysis pHs optima as pH 6.0 and 9.0. Xylanase presented higher Vmax at pH 9.0 (0.87 µmol/mg protein than at pH 6.0 and minor Km at pH 6.0 (7.42 mg/mL than at pH 9.0.Rhizopus stolonifer foi cultivado em meio de farelo de trigo para produzir uma xilanase alcalina celulase-free. Uma amostra parcialmente purificada desta enzima foi obtida após cromatografia de exclusão molecular em Sephacryl S-200 HR. A temperatura ótima de hidrólise determinada (45º C está dentro do intervalo citado na literatura (45º C a 60º C para xilanases microbianas. Quanto ao pH ótimo, a amostra obtida apresentou atividades máximas em pH 6,0 e 9,0. Estes dados diferem da literatura, uma vez que o pH ótimo citado para a maioria das xilanases estudadas varia entre 4,0 e 5,5. De acordo com os estudos cinéticos realizados, a xilanase apresentou maior Vmax em pH 9,0 (0,87 µmol/mg proteína e menor Km em pH 6,0 (7,42 mg/mL. Os dois pHs ótimos determinados podem indicar a presença de isoformas desta enzima. Estes dados são interessantes pelo fato de que enzimas xilanolíticas alcalinas celulase-free podem ser utilizadas para o biobranqueamento da polpa na indústria de papel.

  13. A high performance Trichoderma reesei strain that reveals the importance of xylanase III in cellulosic biomass conversion.

    Science.gov (United States)

    Nakazawa, Hikaru; Kawai, Tetsushi; Ida, Noriko; Shida, Yosuke; Shioya, Kouki; Kobayashi, Yoshinori; Okada, Hirofumi; Tani, Shuji; Sumitani, Jun-ichi; Kawaguchi, Takashi; Morikawa, Yasushi; Ogasawara, Wataru

    2016-01-01

    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 xylan, underscoring the importance of XYN III. To attain optimal saccharifying potential in T. reesei, we constructed two new strains, C1AB1 and E1AB1, in which aabg1 was expressed heterologously by means of the cbh1 or egl1 promoters, respectively, so that the endogenous XYN III synthesis remained intact. Due to the presence of wild-type xyn3 in T. reesei E1AB1, enzymes prepared from this strain were 20-30% more effective in the saccharification of alkaline-pretreated rice straw than enzyme extracts from X3AB1, and also outperformed recent commercial cellulase preparations. Our results demonstrate the importance of XYN III in the conversion of alkaline-pretreated cellulosic biomass by T. reesei.

  14. Novel Cold-adaptive Penicillium Strain FS010 Secreting Thermo-labile Xylanase Isolated from Yellow Sea

    Institute of Scientific and Technical Information of China (English)

    Yun-Hua HOU; Tian-Hong WANG; Hao LONG; Hui-Yuan ZHU

    2006-01-01

    A novel cold-adaptive xylanolytic Penicillium strain FS010 was isolated from Yellow Sea sediments. The marine fungus grew well from 4 to 20 ℃; a lower (0 ℃) or higher (37 ℃) temperature limits its growth. The strain was identified as Penicillium chrysogenum. Compared with mesophilic P. chrysogenum,the cold-adaptive fungus secreted the cold-active xylanase (XYL) showing high hydrolytic activities at low temperature (2-15 ℃) and high sensitivity to high temperature (>50 ℃). The XYL gene was isolated from the cold-adaptive P. chrysogenum FS010 and designated as xyl. The deduced amino acid sequence of the protein encoded by xyl showed high homology with the sequence of glycoside hydrolase family 10. The gene was subcloned into an expression vector pGEX-4T-1 and the encoded protein was overexpressed as a fusion protein with glutathione-S-transferase in Escherichia coli BL21. The expression product was purified and subjected to enzymatic characterization. The optimal temperature and pH for recombinantXYL was 25 ℃ and 5.5, respectively. Recombinant XYL showed nearly 80% of its maximal activity at 4 ℃ and was active in the pH range 3.0-9.5.

  15. Effect of fungal biofertilizer from Chaetomium globosum on growth and quality of strawberry%球毛壳菌生物菌肥对草莓生长和品质的影响

    Institute of Scientific and Technical Information of China (English)

    辛雅芬

    2013-01-01

    [Objective]The present study was conducted to investigate effect of different dosages of fungal biofertilizer from Chaetomium globosum on growth,yield and quality of strawberry to provide references for utilizing the fungal biofertilizer in the field in future.[Method]Zhangji strawberry and fungal biofertilizer from C.globosum were served as test materials.Percentage of colonization of endophytic fungus C.globosum ND35 was detected in strawberry.Effects of fungal biofertilizer with different dosages of C.globosum spores on biomassy,physiological quota of strawberry and production and quality of fruits were investigated and analyzed in the field and in laboratory.[Result]Endophytic fungus C.globosum ND35 was able to colonize within plant of strawberry.Colonization rate was positively related to spores dosages of fungal biofertilizer.Different treatment of fungal biofertilizer from C.globosum significantly influenced growth,yield and quality of strawberry.Applying fungal biofertilizer at 0.5 g/plant and 1.0 g/plant was able to promote growth and development of strawberry.[Conclusion]The 0.5-1.0 g/plant utilizing dosages of fungal biofertilizer from C.globosum was able to increase yield and improve quality of strawberry.%[目的]研究球毛壳菌生物菌肥不同用量对草莓植株生长、果实产量和品质的影响,为球毛壳菌生物菌肥在生产上的应用提供参考.[方法]在温室大棚中开展试验,按不同球毛壳菌生物菌肥施肥量(0.5、1.0、2.0 g/株)设3个处理,不施肥为对照处理,检测内生真菌球毛壳菌ND35在草莓上的定殖率;分析不同菌肥用量对草莓生物量和生理指标及果实产量和品质的影响.[结果]球毛壳菌ND35可以在草莓植株内定殖,其定殖率与菌肥用量正相关.不同处理的球毛壳菌生物菌肥对草莓植株生长、果实产量和品质具有显著影响,施用0.5 g/株和1.0 g/株的菌肥用量有利于草莓的生长和发育.[结论]0.5~1.0/株用量

  16. 纤维素和木聚糖复合诱导合成木聚糖酶的研究%STUDY ON THE PRODUCTION OF XYLANASES CO-INDUCED BY CELLULOSE-XYLAN

    Institute of Scientific and Technical Information of China (English)

    刘超纲; 勇强; 余世袁

    2001-01-01

    This paper deals with the inducing function of cellulose andcellulose-xylan mixture on xylanases production with Trichoderma reesei. It was found that xylanase could be induced by cellulose, whereas cellulose-xylan exhibited a kind of co-inducing function to xylanases, which could greatly improve xylanase activity. Compared to pure xylan(5 g/L) xylanase activity could be increased by 45% by using xylan (4 g/L)-pulp(1 g/L)mixture as carbon source. This result provides the theoretical basis for xylanase production with plant fibre raw materials rich in xylan as carbon source.%以里氏木霉(Trichodermareesei)为产酶菌,分别对纤维素、纤维素和木聚糖诱导产酶的功能进行了研究。研究发现,纤维素具有诱导木聚糖酶合成的功能;纤维素和木聚糖混合对木聚糖酶合成具有促进作用,可大幅度提高木聚糖酶活力。与纯木聚糖(5g/L)产酶相比,纯木聚糖(4g/L)和纸浆(1g/L)混合产酶木聚糖酶活可以提高45%。研究成果为采用富含木聚糖的植物纤维原料作碳源制备木聚糖酶提供了理论依据。

  17. Energy utilization and growth performance of chickens fed novel wheat inbred lines selected for different pentosan levels with and without xylanase supplementation.

    Science.gov (United States)

    Pirgozliev, V; Rose, S P; Pellny, T; Amerah, A M; Wickramasinghe, M; Ulker, M; Rakszegi, M; Bedo, Z; Shewry, P R; Lovegrove, A

    2015-02-01

    Different F5 recombinant inbred lines from the cross Yumai 34×Ukrainka were grown in replicated trials on a single site in one harvest year at Rothamsted Research. A total of 10 samples from those lines were harvested and used in a broiler experiment. Twenty nutritionally complete meal-form diets that had 630 g/kg of wheat with different amounts of pentosan, with and without exogenous xylanase supplementation, were used to compare broiler growth performance and determine apparent metabolizable energy corrected for N retention (AMEn). We examined the relationship between the nutritive value of the wheat samples and their chemical compositions and results of quality tests. The amounts of total and water soluble pentosans in wheat samples ranged from 36.7 to 48.0 g/kg DM, and 6.7 to 11.6 g/kg DM, respectively. The mean crude oil and protein contents of the wheat samples were 10.5 and 143.9 g/kg DM, respectively. The average determined value for the kinematic viscosity was 0.0018 mPa.s, and 2.1 mPa.s for the dynamic viscosity. The AMEn of the wheat-based diets had a maximum range of 0.47 MJ/kg DM within the ten wheat samples that were tested. Xylanase supplementation improved (Ppentosan content. There was a negative relationship between the total pentosan content in the wheat and broiler growth performance. An increase by 10 g of pentosan per kg of wheat reduced (Ppentosan content. Supplementary xylanase improved energy and nutrient availability of all wheat samples that was independent of differences in pentosan content.

  18. Enzymatic hydrolysis of water-soluble wheat arabinoxylan. 1. Synergy between alpha-L-arabinofuranosidases, endo-1,4-beta-xylanases, and beta-xylosidase activities

    DEFF Research Database (Denmark)

    Sørensen, H.R.; Meyer, Anne Boye Strunge; Pedersen, S.

    2003-01-01

    , but a synergistic interaction in xylose release was found between Ultraflo L and Celluclast 1.5 L. On the basis of high-performance anion exchange chromatography (HPAEC) analysis of the hydrolysates after enzymatic reaction, we propose that the observed synergism between Celluclast 1.5 L and Ultraflo L...... is the result of positive interaction between alpha-L-arabinofuranosidase and endo-1,4-beta-xylanase activities present in Ultraflo L that released arabinose, xylobiose and xylotriose, and beta-xylosidase activities in Celluclast 1.5 L, capable of catalyzing the hydrolysis of xylobiose and xylotriose to xylose....

  19. Endogenous N-losses in broilers estimated by a [15N]-isotope dilution technique: effect of dietary fat type and xylanase addition.

    Science.gov (United States)

    Dänicke, S; Jeroch, H; Simon, O

    2000-01-01

    Male broilers were given a low protein diet (15.5% CP) spiked with [15N]H4HCO3 from day 12 to day 18 of age to label the endogenous N-constituents. Experimental diets were subsequently fed from day 19 to day 24 of age and consisted of a rye based diet (56% dietary inclusion) which contained either 10% soya oil (S) or 10% beef tallow (T), each of which was either unsupplemented (-) or supplemented (+) with a xylanase containing enzyme preparation (2700 IU/kg at pH 5.3). [15N]-atom percent excess (APE) of excreta, faeces and urine were monitored on a daily basis during both experimental periods. Furthermore, APE was measured in various tissues at the end of the experiment. The APE of urine on the last day of the experiment was between the APE of the pancreas and that of the jejunal tissue, an observation which supported the usefulness of using urinary APE as an indicator for the endogenous N-pool. Endogenous N-proportions were estimated by an isotope dilution technique at the end of the experiment by examination of the ratio of APE in faeces and urine. The endogenous N-proportion in the faeces was greatest in birds receiving the T(-) diet. The proportions were 0.321, 0.319, 0.451 and 0.289 in S(-), S(+), T(-) and T(+) fed groups, respectively. Xylanase addition reduced endogenous N-proportion, a factor which was used to correct apparent crude protein digestibility (85.6, 86.2, 84.3 and 88.5% in S(-), S(+), T(-) and T(+) fed birds, respectively) for endogenous losses resulting in almost equal true digestibilities of crude protein for all treatments (90.3, 90.6, 90.4 and 91.5%). The amounts of endogenous N in faces were estimated to be 87, 69, 244 and 81 mg per day per kg0.67 body weight in S(-), S(+), T(-) and T(+) fed birds, respectively. It was concluded that xylanase supplementation of a rye based broiler diet does not change endogenous N-secretions when the supplemental fat is soya oil. However, addition of tallow rather than soya oil increased these N

  20. Methane production of two roughage and total mixed ration as influenced by cellulase and xylanase enzyme addition

    Directory of Open Access Journals (Sweden)

    Belete Shenkute Gemeda

    2015-02-01

    Full Text Available In recent decades supplementation of animal feeds with exogenous fibrolytic enzymes has substantially improved digestibility and animal performance. However, information related to associated methane production is limited and inconsistent. This study evaluated the effect of cellulase and xylanase enzymes on in vitro methane production of Eragrostis curvula hay, maize (Zea mays stover and a total mixed ration (TMR at seven levels of the two enzymes. Feed samples were incubated for 2, 12, 24 and 48 h in an in vitro batch culture with buffer and rumen fluid, and fibrolytic enzymes. Gas production was measured using a pressure transducer connected to a data tracker, while methane gas was analysed using a gas chromatograph which was calibrated with standard CH4 and CO2. Increases in the level of enzyme application resulted in increases in gas volume, total volatile fatty acid (VFA production, dry matter (DM disappearance and associated increases in methane production. The linear increase in percentage and volume of methane production in tandem with increases in level of enzyme application might be due to increased fermentation, and organic matter degradability that resulted in a shift in VFA production towards acetate. Considering the efficiency of DM and neutral detergent fiber degradation and production of associated VFA with levels of enzymes, the use of 1 mg g−1 DM of enzyme can be a good option for the feeds tested. However, they cannot decrease methane production. It will be very important to consider other hydrogen sinks that can capture directly extra H+ produced by the addition of enzyme so that their supplementation could be very efficient and environmentally sound.

  1. Novel xylanase from a holstein cattle rumen metagenomic library and its application in xylooligosaccharide and ferulic Acid production from wheat straw.

    Science.gov (United States)

    Cheng, Fansheng; Sheng, Jiping; Dong, Rubo; Men, Yejun; Gan, Lin; Shen, Lin

    2012-12-26

    A novel gene fragment containing a xylanase was identified from a Holstein cattle rumen metagenomic library. The novel xylanase (Xyln-SH1) belonged to the glycoside hydrolase family 10 (GH10) and exhibited a maximum of 44% identity to the glycoside hydrolase from Clostridium thermocellum ATCC 27405. Xyln-SH1 was heterologously expressed, purified, and characterized. A high level of activity was obtained under the optimum conditions of pH 6.5 and 40 °C. A substrate utilization study indicated that Xyln-SH1 was cellulase-free and strictly specific to xylan from softwood. The synergistic effects of Xyln-SH1 and feruloyl esterase (FAE-SH1) were observed for the release of xylooligosaccharides (XOS) and ferulic acid (FA) from wheat straw. In addition, a high dose of Xyln-SH1 alone was observed to improve the release of FA from wheat straw. These features suggest that this enzyme has substantial potential to improve biomass degradation and industrial applications.

  2. The effects of transportation stress on Japanese quail (Coturnix Coturnix japonica) fed corn-based diet in comparison with wheat-based diet supplemented with xylanase and phytase.

    Science.gov (United States)

    Mehraei Hamzekolaei, M H; Zamani Moghaddam, A K; Tohidifar, S S; Dehghani Samani, A; Heydari, A

    2016-08-01

    Harvesting, handling and transporting quails to the slaughterhouses, other farms and laboratories might covertly reduce their welfare. The aim of this study was to evaluate the effects of two major sources of energy in poultry nutrition on reducing transportation stress in Japanese quail (Coturnix Coturnix japonica). Male quails (n = 60) were divided into two groups. The first group was fed corn-based diet, and the second was fed wheat-based diet supplemented with xylanase and phytase. At the end of the experiment (day 35), quails were subjected to 80 km of transportation. Immediately on arrival and after 24 h, heterophil counts, lymphocyte counts and H:L ratios were measured. On arrival, H counts were lower, L counts were higher, and H:L ratios were lower for corn-fed group. After 24 h, wheat-fed group showed lower increment of H counts, greater increment of L counts and also decrement of H:L ratios rather than corn-fed group which showed increment of H:L ratios. However, these ratios were still lower in corn-fed group. Results indicate that corn-based diets can help Japanese quail to better resist transportation stress, although it seems that feeding wheat-based diets supplemented with xylanase and phytase could have positive effects for coping better with stress after journeys. PMID:26459218

  3. Biological synthesis of Au nanoparticles using liquefied mash of cassava starch and their functionalization for enhanced hydrolysis of xylan by recombinant xylanase.

    Science.gov (United States)

    Zeng, Sumei; Du, Liangwei; Huang, Meiying; Feng, Jia-Xun

    2016-05-01

    Au nanoparticles (AuNPs) have shown the potential for a variety of applications due to their unique physical and chemical properties. In this study, a facile and affordable method for the synthesis of AuNPs via the liquefied mash of cassava starch has been described and the functionalized AuNPs by L-cysteine improved activity of recombinant xylanase was demonstrated. UV-Vis absorption spectroscopy, transmission electron microscopy, and zeta potential measurements were performed to characterize the AuNPs and monitor their synthesis. The presence of Au was confirmed by energy-dispersive X-ray spectroscopy (EDX) and the X-ray diffraction patterns showed that Au nanocrystals were face-centered cubic. The C=O stretching vibration in the Fourier transform infrared spectrum of AuNPs suggested that the hemiacetal C-OH of sugar molecules performed the reduction of Au(3+) to Au(0). The presence of C and O in the EDX spectrum and the negative zeta potential of AuNPs suggested that the biomolecules present in liquefied cassava mash were responsible for the stabilization of AuNPs. The surface of AuNPs was easily functionalized by L-cysteine, which improved the stability of AuNPs. Moreover, cysteine-functionalized AuNPs could significantly improve recombinant xylanase efficiency and stability. PMID:26864877

  4. Purification, crystallization and crystallographic analysis of Clostridium thermocellum endo-1,4-β-d-xylanase 10B in complex with xylohexaose

    International Nuclear Information System (INIS)

    The N-terminal moiety of C. thermocellum endo-1,4-β-d-xylanase 10B, comprising a carbohydrate-binding module (CBM22-1) and a GH10 E337A mutant domain, has been crystallized in complex with xylohexaose. The crystals belong to the trigonal space group P3221, contain a dimer in the asymmetric unit and diffract to beyond 2.0 Å resolution. The cellulosome of Clostridium thermocellum is a highly organized multi-enzyme complex of cellulases and hemicellulases involved in the hydrolysis of plant cell-wall polysaccharides. The bifunctional multi-modular xylanase Xyn10B is one of the hemicellulase components of the C. thermocellum cellulosome. The enzyme contains an internal glycoside hydrolase family 10 catalytic domain (GH10) and a C-terminal family 1 carbohydrate esterase domain (CE1). The N-terminal moiety of Xyn10B (residues 32–551), comprising a carbohydrate-binding module (CBM22-1) and the GH10 E337A mutant, was crystallized in complex with xylohexaose. The crystals belong to the trigonal space group P3221 and contain a dimer in the asymmetric unit. The crystals diffracted to beyond 2.0 Å resolution

  5. Purification, crystallization and crystallographic analysis of Clostridium thermocellum endo-1,4-β-d-xylanase 10B in complex with xylohexaose

    Energy Technology Data Exchange (ETDEWEB)

    Najmudin, Shabir, E-mail: shabir@dq.fct.unl.pt [REQUIMTE, Departamento de Química, FCT-UNL, 2829-516 Caparica (Portugal); Pinheiro, Benedita A. [CIISA - Faculdade de Medicina Veterinária, Universidade Técnica de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa (Portugal); Romão, Maria J. [REQUIMTE, Departamento de Química, FCT-UNL, 2829-516 Caparica (Portugal); Prates, José A. M.; Fontes, Carlos M. G. A., E-mail: shabir@dq.fct.unl.pt [CIISA - Faculdade de Medicina Veterinária, Universidade Técnica de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa (Portugal); REQUIMTE, Departamento de Química, FCT-UNL, 2829-516 Caparica (Portugal)

    2008-08-01

    The N-terminal moiety of C. thermocellum endo-1,4-β-d-xylanase 10B, comprising a carbohydrate-binding module (CBM22-1) and a GH10 E337A mutant domain, has been crystallized in complex with xylohexaose. The crystals belong to the trigonal space group P3{sub 2}21, contain a dimer in the asymmetric unit and diffract to beyond 2.0 Å resolution. The cellulosome of Clostridium thermocellum is a highly organized multi-enzyme complex of cellulases and hemicellulases involved in the hydrolysis of plant cell-wall polysaccharides. The bifunctional multi-modular xylanase Xyn10B is one of the hemicellulase components of the C. thermocellum cellulosome. The enzyme contains an internal glycoside hydrolase family 10 catalytic domain (GH10) and a C-terminal family 1 carbohydrate esterase domain (CE1). The N-terminal moiety of Xyn10B (residues 32–551), comprising a carbohydrate-binding module (CBM22-1) and the GH10 E337A mutant, was crystallized in complex with xylohexaose. The crystals belong to the trigonal space group P3{sub 2}21 and contain a dimer in the asymmetric unit. The crystals diffracted to beyond 2.0 Å resolution.

  6. High-level soluble expression of a thermostable xylanase from thermophilic fungus Thermomyces lanuginosus in Escherichia coli via fusion with OsmY protein.

    Science.gov (United States)

    Le, Yilin; Wang, Huilei

    2014-07-01

    A thermostable xylanase is encoded by xynA from fungus Thermomyces lanuginosus. The problem emerged from overexpression of xynA in Escherichia coli has been the formation of inclusion bodies. Here we describe the xynA was fused with the hyperosmotically inducible periplasmic protein of E. coli, OsmY. The fusion protein OsmY-xynA was expressed as almost all soluble form. The soluble expression level of fusion protein reached 98±6U/ml when cells containing pET-OsmY-xynA were expressed without IPTG induction at 37°C. The induction is probably due to auto-induction due to lactose in the medium (Studier (2005) [21]). The cells harboring pET-OsmY-xynA expressed an activity level about 24 times higher than that expressed from pET-20b-xynA. Xylanase activity was observed in the extracellular (36±1.3U/ml) and the periplasmic (42±4U/ml) when cells containing pET-OsmY-xynA were induced without IPTG addition. After the cold osmotic shock procedure followed by nickel affinity chromatography, the purified fusion protein showed a single band on SDS-PAGE gel with a molecular mass of 44kDa. The purified fusion enzyme exhibited the highest activity at 65°C and pH 6.0. PMID:24657705

  7. Conservation of XYN11A and XYN11B xylanase genes in Bipolaris sorghicola, Cochliobolus sativus, Cochliobolus heterostrophus, and Cochliobolus spicifer.

    Science.gov (United States)

    Emami, Kaveh; Hack, Ethan

    2002-10-01

    Two types of xylanase gene, XYN11A ( XYL1) and XYN11B ( XYL2), were amplified by PCR and partially sequenced in four phytopathogenic species of the ascomycete fungal genus Cochliobolus (anamorph genus Bipolaris). Three of the species, C. heterostrophus ( B. maydis), C. sativus ( B. sorokiniana), and Bipolaris sorghicola (no teleomorph known), are interrelated; the fourth, C. spicifer ( B. spicifera), was found, through analysis of the 5.8S RNA and internal transcribed spacer (ITS) sequences of its ribosomal DNA, to be more distantly related to the other three. Isolates from all four species contain orthologous XYN11A and XYN11B genes, but a set of laboratory strains of C. heterostrophus gave no product corresponding to the XYN11B gene. The patterns of evolution of the two xylanase genes and ribosomal DNA sequences are mutually consistent; the results indicate that the two genes were present in the common ancestor of all Cochliobolus species and are evolving independently of each other.

  8. The modular xylanase Xyn10A from Rhodothermus marinus is cell-attached, and its C-terminal domain has several putative homologues among cell-attached proteins within the phylum Bacteroidetes

    DEFF Research Database (Denmark)

    Karlsson, Eva Nordberg; Hachem, Maher Abou; Ramchuran, Santosh;

    2004-01-01

    Until recently, the function of the fifth domain of the thermostable modular xylanase Xyn10A from Rhodothermus marinus was unresolved. A putative homologue to this domain was however identified in a mannanase (Man26A) from the same microorganism which raised questions regarding a common function....

  9. Purification and characterization of a low molecular weight xylanase from solid-state cultures of Aspergillus fumigatus Fresenius Purificação e caracterização de uma xilanase de baixo peso molecular de culturas de estado sólido de Aspergillus fumigatus Fresenius

    OpenAIRE

    Claudio Henrique Cerri e Silva; Jurgen Puls; Marcelo Valle de Sousa; Edivaldo Ximenes Ferreira Filho

    1999-01-01

    A xylan-degrading enzyme (xylanase II) was purified to apparent homogeneity from solid-state cultures of Aspergillus fumigatus Fresenius. The molecular weight of xylanase II was found to be 19 and 8.5 kDa, as estimated by SDS-PAGE and gel filtration on FPLC, respectively. The purified enzyme was most active at 55 °C and pH 5.5. It was specific to xylan. The apparent Km and Vmax values on soluble and insoluble xylans from oat spelt and birchwood showed that xylanase II was most active on solub...

  10. 牦牛瘤胃元基因组文库中木聚糖酶基因的分析%Analysis of xylanases derived from the metagenomic BAC clone library of yak rumen

    Institute of Scientific and Technical Information of China (English)

    王敏; 陈富荣; 张山; 朱雅新; 东秀珠; 黄力; 田瑞华; 董志扬; 戴欣

    2011-01-01

    [ Objective ] The diversity of rumen microbial xylanases and their degradation characteristics were studied and the resources of new xylanases genes and enzymes were provided. [ Methods ] According to the result of the high-throughput sequencing of the rumen microbial metagenome bacterial artificial chromosome ( B AC ) clones library, the diversity of xylanase genes was analyzed and screened. Then one xylanase and its downstream xylosidase gene screened was cloned and expressed in Escherichia coli. The enzyme characterization of the recombinant xylanase and xylosidase and their synergistic effect were studied. [Results] All 14 xylanases screened from the library belong to GH10 family proteins. These xylanases shared the amino acid sequence similarity between 20. 5% and 91. 3% . Intriguingly, 7 xylanase genes in different contigs were found to be followed by xylosidase gene. The specific enzyme activity of the xylanase (Xyn32) was 1.98 U/mg and no ferulic acid esterase activity was detected. The specific enzyme activity of the coupled xylosidase (Xyl33) was 0.07 IU/mg, and xylosidase ( Xyl33 ) also displayed the activity of arabinofuranosidase. In addition, the in vitro experiment confirmed the synergistic effect between the coupled xylanase and xylosidase.%[目的]了解牦牛瘤胃微生物木聚糖酶多样性及其降解特征,为木聚糖降解提供新的基因资源.[方法]根据对已构建的瘤胃微生物元基因组细菌人工染色体( BAC)克隆文库高通量测序结果的注释,筛选其中编码木聚糖酶的基因并进行多样性分析;对其中一个木聚糖酶基因及其连锁的木糖苷酶基因进行克隆表达和酶学性质表征,分析其协同作用.[结果]共筛选到14个木聚糖酶基因,均编码GH1O家族木聚糖酶,其氨基酸序列之间的相似性为20.5% -91.3%;其中7个木聚糖酶基因所在的不同的DNA片段(contig)上存在木糖苷酶基因,编码的木糖苷酶属于GH43或GH3糖苷水解酶家

  11. High-level recombinant protein production by the basidiomycetous yeast Pseudozyma antarctica under a xylose-inducible xylanase promoter.

    Science.gov (United States)

    Watanabe, Takashi; Morita, Tomotake; Koike, Hideaki; Yarimizu, Tohru; Shinozaki, Yukiko; Sameshima-Yamashita, Yuka; Yoshida, Shigenobu; Koitabashi, Motoo; Kitamoto, Hiroko

    2016-04-01

    Yeast host-vector systems are useful tools for the production of recombinant proteins. Here, we report the construction of a new high-level expression plasmid pPAX1-neo for the basidiomycetous yeast, Pseudozyma antarctica. pPAX1-neo harbours a xylose-inducible expression cassette under control of the xylanase promoter and terminator of P. antarctica T-34, a selection cassette of neomycin/G418 with an Escherichia coli neomycin resistance gene under control of the homocitrate synthase promoter of strain T-34, and an autonomously replicating sequence fragment of Ustilago maydis (UARS). Biodegradable plastic (BP)-degrading enzymes of P. antarctica JCM10317 (PaE) and Paraphoma-related fungal strain B47-9 (PCLE) were used as reporter proteins and inserted into pPAX1-neo, resulting in pPAX1-neo::PaCLE1 and pPAX1-neo::PCLE, respectively. Homologous and heterologous BP-degrading enzyme production of transformants of P. antarctica T-34 were detected on agar plates containing xylose and emulsified BP. Recombinant PaE were also produced by transformants of other Pseudozyma strains including Pseudozyma aphidis, Pseudozyma rugulosa, and Pseudozyma tsukubaensis. To improve the stability of transformed genes in cells, the UARS fragment was removed from linearized pPAX1-neo::PaCLE1 and integrated into the chromosome of the P. antarctica strain, GB-4(0), which was selected as a PaE producer in xylose media. Two transformants, GB-4(0)-X14 and X49, had an 11-fold higher activity compared with the wild type strain in xylose-containing liquid media. By xylose fed-batch cultivation using a 3-L jar fermentor, GB-4(0)-X14 produced 73.5 U mL(-1) of PaE, which is 13.4-fold higher than that of the wild type strain GB-4(0), which produced 5.5 U mL(-1) of PaE. PMID:26695155

  12. 球毛壳ND35对植物生长的影响及其生防效果%Effect of Chaetomium globosum ND35 on Plant Growth and Preliminary Study of Its Biocontrol Efficacy

    Institute of Scientific and Technical Information of China (English)

    余新燕; 孟庆果; 任思栋; 刘振叶; 王茂云; 高克祥

    2009-01-01

    [Objective] The aim was to study effect of Chaetomium globosum ND35 on plant growth and preliminary study of its biocontrol efficacy, and provide basis for popularization and application of this strain. [Method] With endophytic fungus C.globosum ND35 as a tested strain, effect of C.globosum ND35 on plant growth and its biocontrol on five plant diseases were investigated in the greenhouse and field. [Result] The results showed that ND35 promoted growth of lateral root and diameter of breast height of poplar. ND35 can induce poplar to resist Poplar Valsa Canker caused by Valsa sordida and Poplar Rust caused by Melampsora puplicola. ND35 was also able to induce tomato and bean to resist Botrytis cinera. Biocontrol of Bean Stem Rot Rhizoctonia by ND35 was effective as well. [Conclusion] Induced systemic resistance by endophytic C.globosum ND35 plays an important role in biocontrol of plant diseases.%[目的]研究球毛壳ND35对植物生长的影响及其生防效果,为该菌的推广应用提供依据.[方法]以植物内生真菌球毛壳ND35为供试菌株,病原菌有杨树腐烂病菌、立枯丝核菌、番茄灰霉菌.(a)调查球毛壳ND35对植物生长的影响.在扦插杨树枝条时,设2个处理:①接种10 g长有球毛壳ND35的麦粒培养基;②接种10 g无球毛壳ND35的麦粒培养基为对照.出芽后,测量杨树高度、1.3 m处的胸径,同时调查侧根(d≥8 mm)数量.(b)大田试验测定球毛壳ND35对杨树腐烂病的拮抗作用.采用烫伤接种的方法,在主干距地面高50 cm和100 cm(约树干的1/3和2/3)处先用火烫伤树皮,再接种含病原菌菌丝体的PDA菌饼.在随后的1个多月统计发病情况,以29 d后发病的为0级,26~28 d发病的为1级,23~25 d发病的为2级,20~22 d发病的为3级,19 d之内发病的为4级.分级计数,计算发病率、病情指数和拮抗效果.(c)大田试验调查球毛壳ND35对杨树叶锈病的拮抗作用.在杨树1.3、1.7、2.1 m处分别调查2个处理组杨

  13. 小麦饲粮中添加木聚糖酶对肉鹅血糖和血清总蛋白水平的影响%Effect of Wheat Based Diet Supplemented with Xylanase on Blood Sugar and Total Protein in Serum of Geese

    Institute of Scientific and Technical Information of China (English)

    王佳丽; 史东辉; 杨桂芹

    2008-01-01

    [Objective] The effects of wheat based diet supplemented with xylarmse on blood sugar and total protein in serum of geese were studied. [Method] By using the randomized design of single factor, the 1-day-old healthy goslings were divided into 6 groups and fed with corn based diet, wheat based diet and wheat based diet supplemented with xylanase at different concentrations respectively, the contents of blood sugar and total protein in serum were determined. [Result] The wheat based diet supplemented with xylanase could increase the blood sugar and total protein in serum of geese and wheat based diet supplemented with 0.2% xylanase generated the best effect, which was higher than those of corn based diet group. As for the concentration of protein in senun, wheat based diet supplemented with O. 2% xylarmse was significantly different from corn based diet and wheat based diet. [Conclusion] The wheat based diet supplemented with xylanase could enhance geese production.

  14. Production and purification of an Endo–1,4-beta-Xylanase from Humicola grisea var. thermoidea by electroelution Produção e purificação de uma Endo–1,4-beta-Xylanase de Humicola grisea var. thermoidea por eletroeluição

    Directory of Open Access Journals (Sweden)

    Rubens Monti

    2003-06-01

    Full Text Available Humicola grisea var. thermoidea produces two forms of extracellular xylanase. The component form 1 was purified using the electroelution method, due to the very small production of this extracellular enzyme. The apparent molecular mass was 61.8 kDa by SDS-PAGE.Humicola grisea var. thermoidea produz duas formas de xilanase extracelular. A componente forma 1 foi purificada usando o método de eletroeluição devido à baixa produção desta enzima extracelular. A aparente massa molar foi determinada 61,8 kDa por SDS-PAGE.

  15. Production and purification of an Endo–1,4-beta-Xylanase from Humicola grisea var. thermoidea by electroelution Produção e purificação de uma Endo–1,4-beta-Xylanase de Humicola grisea var. thermoidea por eletroeluição

    OpenAIRE

    Rubens Monti; Leonardo Cardello; Marcos F. Custódio; Antonio J Goulart; Adriana H. Sayama; Jonas Contiero

    2003-01-01

    Humicola grisea var. thermoidea produces two forms of extracellular xylanase. The component form 1 was purified using the electroelution method, due to the very small production of this extracellular enzyme. The apparent molecular mass was 61.8 kDa by SDS-PAGE.Humicola grisea var. thermoidea produz duas formas de xilanase extracelular. A componente forma 1 foi purificada usando o método de eletroeluição devido à baixa produção desta enzima extracelular. A aparente massa molar foi determinada ...

  16. Production and characterization of an enzyme complex from a new strain of Clostridium thermocellum with emphasis on its xylanase activity Produção e caracterização de um complexo enzimático de uma nova linhagem de Clostridium thermocellum com enfase em sua atividade de xilanase

    OpenAIRE

    Werner Bessa Vieira; Leonora Rios de Souza Moreira; Amadeu Monteiro Neto; Edivaldo Ximenes Ferreira Filho

    2007-01-01

    A new bacterial strain (ISO II) was isolated from manure cow and identified as phylogenetically close to the thermophilic cellulolytic bacterium Clostridium thermocellum. The new strain produced extracellular xylanase, pectinase, mannanase and cellulase activities when grown in liquid culture medium containing banana stem as carbon source. The enzyme production profile after growth on banana stem showed that xylanase and cellulase activities were detected in different incubation periods. An e...

  17. Evaluation of high dietary inclusion of distillers dried grains with solubles and supplementation of protease and xylanase in the diets of broiler chickens under necrotic enteritis challenge.

    Science.gov (United States)

    Barekatain, M R; Antipatis, C; Rodgers, N; Walkden-Brown, S W; Iji, P A; Choct, M

    2013-06-01

    A 2 × 2 × 2 factorial experiment was conducted to investigate the effect of a high level of sorghum distillers dried grains with solubles (DDGS; 20%), with or without a combination of protease and xylanase in broiler chickens, under a necrotic enteritis disease challenge. A total of 576 male broiler chicks were randomly assigned to 8 experimental treatments, each replicated 6 times, with 12 birds per replicate for 35 d. Oral inoculation of the challenged group with Eimeria spp. occurred on d 9, followed by 3 consecutive inoculations of Clostridium perfringens from d 14 through 16. The disease challenge and DDGS inclusion significantly (P enteritis-related lesions (d 17) were more severe (P enteritis. Supplementation of enzymes did not reveal significant mitigation effect in infected birds but helped the birds fed DDGS to maintain feed intake and BW gain.

  18. Use of Residual Biomass from the Textile Industry as Carbon Source for Production of a Low-Molecular-Weight Xylanase from Aspergillus oryzae

    Directory of Open Access Journals (Sweden)

    Gilvan Caetano Duarte

    2012-10-01

    Full Text Available Pretreated dirty cotton residue (PDCR from the textile industry was used as an alternative carbon source for the submerged cultivation of Aspergillus oryzae and the production of xylanases. The filtered culture supernatant was fractionated by ultrafiltration followed by three chromatographic steps, which resulted in the isolation of a homogeneous low-molecular-weight xylanase (Xyl-O1 with a mass of 21.5 kDa as determined by sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE co-polymerized with 0.1% oat spelt xylan. Enzyme catalysis was the most efficient at 50 °C and pH 6.0. The Km values (mg·mL−1 for the soluble fraction of oat spelt and birchwood xylans were 10.05 and 3.34, respectively. Xyl-O1 was more stable in the presence of 5,5-dithio-bis-(2-nitrobenzoic acid (DTNB, 1,4-dithiothreitol (DTT, l-cysteine or β-mercaptoethanol, which increased the rate of catalysis by 40%, 14%, 40% or 37%, respectively. The enzyme stability was improved at pH 7.0 in the presence of 20 mM l-cysteine, with the retention of nearly 100% of the activity after 6 h at 50 °C. Xyl-O1 catalyzed the cleavage of internal β-1,4 linkages of the soluble substrates containing d-xylose residues, with a maximum efficiency of 33% for the hydrolysis of birchwood xylan after 12 h of incubation. Identification of the hydrolysis products by high-performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD indicated the predominance of the hydrolysis products X2-X6 during the first 12 h of incubation and the accumulation of higher xylooligomers after the elution of the last xylooligomer standard, xylohexaose.

  19. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1

    Science.gov (United States)

    Gottschalk, Leda Maria Fortes; de Sousa Paredes, Raquel; Teixeira, Ricardo Sposina Sobral; da Silva, Ayla Sant’Ana; da Silva Bon, Elba Pinto

    2013-01-01

    The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 °C and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture. PMID:24294256

  20. 一株产木聚糖酶嗜热菌的鉴定及酶学性质%Identification of a thermophilic bacterium and preliminary characterization of the secreted xylanase

    Institute of Scientific and Technical Information of China (English)

    陈学敏; 刘培培; 张波

    2011-01-01

    从云南腾冲热泉水样中分离筛选得到一株产木聚糖酶的菌株.通过细菌形态观察、生理生化特性并结合16S rDNA序列分析,经鉴定,该菌为地芽孢杆菌(Geobacillus sp.),命名为Geobacillus sp.PZH1.对该菌株所产嗜热木聚糖酶及酶学特性进行了初步研究.SDS-PAGE和酶谱分析测得该酶分子量约为69 kD;酶的最适反应pH和最适反应温度分别为7.0和70℃,在pH 5.0-11.0和40℃-100℃范围内均有较高酶活;该酶在pH 5.0-12.0范围内和70℃以内具有较高的稳定性:40℃-100℃范围内,该木聚糖酶没有被检测到纤维素酶活性.%The bacterium isolated from a water sample of Yunnan tengchong hot spring can secrete a kind of thermophilic xylanase. It was identified and named as Geobacillus sp. PZH1 by morphologic observation, physio-biochemical characteristics and 16S rDNA sequence alignment. Subsequently, its secreted xylanase and the xylanase's characteristics were researched preliminarily. SDS-PAGE electrophoresis and zymogram analysis suggested that the xylanase's molecular mass was 69 kD; the optimum pH and temperature of the partially purified enzyme were 7.0 and 70 ℃ respectively, and it performed noted activities from pH 5.0 to pH 11.0 and from 40 ℃ to 100 ℃; it had high stability from pH 5.0 to pH 12.0 and under 70 ℃; from 40 ℃ to 100 ℃, no cellulase activity was detected for the partially purified xylanase.

  1. 组合型木聚糖酶对21日龄黄羽肉鸡器官指数、内源消化酶活性以及肠道吸收功能的影响%Effect of combination xylanase on organ index,endogenous digestive enzyme activity and absorptive function of intestinal tract for yellow-feather broilers

    Institute of Scientific and Technical Information of China (English)

    徐昌领; 左建军; 冯定远

    2011-01-01

    This study was conducted to evaluate effects on animal organ and the difference between single xylanase and combinative xylanase by measuring organ index, secretion level of pepsin, trypsin,lipase and amylase and xylose in serum of 21-day Yellow-feather broiler.The indexes of liver, gizzard, glandular stomach, duodenum, jejunum and ileum were decreased and the pancreas index was increased with xylanase addtion in wheat-soybean meal diet.Moreover,the secretion levels of pepsin and trypsin were enhanced with xylanase supplementation.In addition, small intestine index was lowered with xylanase cocktail addtion than single xylanase.The secretion of lipase was enhanced with single xylanase supplementation than combinative xylanase.However, no difference was observed.The level of xylose in serum was increased when corn was replaced by wheat as engergy feed,which was lowered with xylanase supplementation.There was no difference among different treatments.%通过对21日龄黄羽肉鸡器官指数和胃蛋白酶、胰蛋白酶、胰脂肪酶、胰淀粉酶以及血清中木糖水平进行检测,研究酶制剂对动物内脏器官所产生的影响,以及组合酶和单酶之间的差异.木聚糖酶在小麦型日粮中添加,降低了肝脏、肌胃、腺胃、十二指肠、空肠和回肠的器官指数,增加了胰腺的器官指数;降低了胃蛋白酶和胰蛋白酶的分泌水平;组合酶比单酶降低小肠器官指数更明显,单酶增加了胰脂肪酶的分泌水平,组合酶降低了胰脂肪酶的分泌水平,差异不显著(P>0.05).小麦型日粮饲喂组血清中木糖的水平高于玉米型日粮组和加酶组,酶制剂的添加降低了血液中的木糖水平,各处理组之间差异不显著(P>0.05).

  2. A xylanase with broad pH and temperature adaptability from Streptomyces megasporus DSM 41476, and its potential application in brewing industry.

    Science.gov (United States)

    Qiu, Zhenhua; Shi, Pengjun; Luo, Huiying; Bai, Yingguo; Yuan, Tiezheng; Yang, Peilong; Liu, Suchun; Yao, Bin

    2010-05-01

    A xylanase gene, xynAM6, was isolated from the genomic DNA library of Streptomyces megasporus DSM 41476 using colony PCR screening method. The 1440-bp full-length gene encodes a 479-amino acid peptide consisting of a putative signal peptide of 36 residues, a family 10 glycoside hydrolase domain and a family 2 carbohydrate-binding module. The mature peptide of xynAM6 was successfully expressed in Pichia pastoris GS115. The optimal pH and temperature were pH 5.5 and 70°C, respectively. The enzyme showed broad temperature adaptability (>60% of the maximum activity at 50-80°C), had good thermostability at 60°C and 70°C, remained stable at pH 4.0-11.0, and was resistant to most proteases. The Km and Vmax values for oat spelt xylan were 1.68mgml(-1) and 436.76μmolmin(-1)mg(-1), respectively, and 2.33mgml(-1) and 406.93μmolmin(-1)mg(-1) for birchwood xylan, respectively. The hydrolysis products of XYNAM6 were mainly xylose and xylobiose. Addition of XYNAM6 (80U) to the brewery mash significantly reduced the filtration rate and viscosity by 36.33% and 35.51%, respectively. These favorable properties probably make XYNAM6 a good candidate for application in brewing industry.

  3. A 24.7-kDa copper-containing oxidase, secreted by Thermobifida fusca, significantly increasing the xylanase/cellulase-catalyzed hydrolysis of sugarcane bagasse.

    Science.gov (United States)

    Chen, Cheng-Yu; Hsieh, Zhi-Shen; Cheepudom, Jatuporn; Yang, Chao-Hsun; Meng, Menghsiao

    2013-10-01

    Thermobifida fusca is a moderately thermophilic soil bacterium belonging to Actinobacteria. It has been known for its capability to degrade plant cell wall polymers except lignin and pectin. To know whether it can produce enzymes to facilitate lignin degradation, the extracellular proteins bound to sugarcane bagasse were harvested and identified by liquid chromatography tandem mass spectrometry. Among the identified proteins, a putative copper-containing polyphenol oxidase of 241 amino acids, encoded by the locus Tfu_1114, was thought to presumably play a role in lignin degradation. This protein (Tfu1114) was thus expressed in E. coli and characterized. Similarly to common laccases, Tfu1114 is able to catalyze the oxidation reaction of phenolic and nonphenolic lignin related compounds such as 2,6-dimethoxyphenol and veratryl alcohol. More interestingly, it can significantly enhance the enzymatic hydrolysis of bagasse by xylanase and cellulase. Tfu1114 is stable against heat, with a half-life of 4.7 h at 90 °C, and organic solvents. It is sensitive to ethylenediaminetetraacetic acid and reducing agents but resistant to sodium azide, a potent inhibitor of laccases. Atomic absorption spectroscopy indicated that the ratio of copper to the protein monomer is 1, instead of 4, a feature of classical laccases. All these data suggest that Tfu1114 is a novel oxidase with laccase-like activity, potentially useful in biotechnology application. PMID:23377789

  4. A computational method for the systematic screening of reaction barriers in enzymes: Searching for Bacillus circulans xylanase mutants with greater activity towards a synthetic substrate

    CERN Document Server

    Hediger, Martin R; De Vico, Luca; Jensen, Jan H

    2013-01-01

    We present a semi-empirical (PM6-based) computational method for systematically estimating the effect of all possible single mutants, within a certain radius of the active site, on the barrier height of an enzymatic reaction. The intent of this method is not a quantitative prediction of the barrier heights, but rather to identify promising mutants for further computational or experimental study. The method is applied to identify promising single and double mutants of Bacillus circulans xylanase (BCX) with increased hydrolytic activity for the artificial substrate ortho-nitrophenyl \\beta-xylobioside (ONPX$_2$). The estimated reaction barrier for wild-type (WT) BCX is 18.5 kcal/mol, which is in good agreement with the experimental activation free energy value of 17.0 kcal/mol extracted from the observed k$_\\text{cat}$ using transition state theory (Joshi et al., Biochemistry 2001, 40, 10115). The PM6 reaction profiles for eight single point mutations are recomputed using FMO-MP2/PCM/6-31G(d) single points. PM6 ...

  5. Selection of Bacillus spp. for Cellulase and Xylanase Production as Direct-Fed Microbials to Reduce Digesta Viscosity and Clostridium perfringens Proliferation Using an in vitro Digestive Model in Different Poultry Diets

    Science.gov (United States)

    Latorre, Juan D.; Hernandez-Velasco, Xochitl; Kuttappan, Vivek A.; Wolfenden, Ross E.; Vicente, Jose L.; Wolfenden, Amanda D.; Bielke, Lisa R.; Prado-Rebolledo, Omar F.; Morales, Eduardo; Hargis, Billy M.; Tellez, Guillermo

    2015-01-01

    Previously, our laboratory has screened and identified Bacillus spp. isolates as direct-fed microbials (DFM). The purpose of the present study was to evaluate the cellulase and xylanase production of these isolates and select the most appropriate Bacillus spp. candidates for DFM. Furthermore, an in vitro digestive model, simulating different compartments of the gastrointestinal tract, was used to determine the effect of these selected candidates on digesta viscosity and Clostridium perfringens proliferation in different poultry diets. Production of cellulase and xylanase were based on their relative enzyme activity. Analysis of 16S rRNA sequence classified two strains as Bacillus amyloliquefaciens and one of the strains as Bacillus subtilis. The DFM was included at a concentration of 108 spores/g of feed in five different sterile soybean-based diets containing corn, wheat, rye, barley, or oat. After digestion time, supernatants from different diets were collected to measure viscosity, and C. perfringens proliferation. Additionally, from each in vitro simulated compartment, samples were taken to enumerate viable Bacillus spores using a plate count method after heat-treatment. Significant (P < 0.05) DFM-associated reductions in supernatant viscosity and C. perfringens proliferation were observed for all non-corn diets. These results suggest that antinutritional factors, such as non-starch polysaccharides from different cereals, can enhance viscosity and C. perfringens growth. Remarkably, dietary inclusion of the DFM that produce cellulase and xylanase reduced both viscosity and C. perfringens proliferation compared with control diets. Regardless of diet composition, 90% of the DFM spores germinated during the first 30 min in the crop compartment of the digestion model, followed by a noteworthy increased in the intestine compartment by ~2log10, suggesting a full-life cycle development. Further studies to evaluate in vivo necrotic enteritis effects are in

  6. 嗜热菌Geobacillus sp.PZH1产木聚糖酶发酵条件的优化%Optimization of fermentation conditions of xylanase from thermophilic bacterium Geobacillus sp.PZH1

    Institute of Scientific and Technical Information of China (English)

    刘培培; 陈学敏; 王石峰; 张波

    2012-01-01

    The culture conditions for alkali-thermo-stable xylanase production from the thermophilic bacterium Geobacillus sp.PZH1 were optimized.Five factors,such as carbon source,nitrogen source,initial pH,inoculum size and fermentation temperature,were researched in single-factor experiment.C/N ratio,initial pH and inoculum size were researched in orthogonal experiment.The results showed that the xylanase yield reached a highest level for 7d culture,and the best combination of fermentation conditions for alkali-thermo-stable xylanase production from the thermophilic bacterium Geobacillus sp.PZH1 was brichwood xylan as carbon source,beef extract as nitrogen source,C N ratio 2∶3,initial pH 7.0,inoculum size 4%,fermentation temperature 50℃ and fermentation time 7d.Under these optimal conditions,the xylanase production from the thermophilic bacterium Geobacillus sp.PZH1 was 2.56IU/mL,1.44 fold higher than that before the optimization.%对嗜热菌Geobacillus sp.PZH1发酵产嗜热耐碱木聚糖酶的培养条件进行了优化研究。对碳源、氮源、初始pH、接种量以及发酵温度五个因素进行了单因素实验,在此基础上对碳氮比、初始pH以及接种量进行了正交实验。结果表明,该菌株在发酵培养7d时有最大产酶量,Geobacillus sp.PZH1发酵产木聚糖酶最佳发酵条件为:桦木木聚糖为碳源,牛肉膏为氮源,碳氮比2∶3,初始pH7.0,接种量4%,发酵温度50℃,发酵时间7d。在最佳产酶条件下进行发酵,木聚糖酶活力可达2.56IU/mL,是未优化前酶活的1.44倍。

  7. ENZYMATIC PRETREATMENT WITH XYLANASE FOR IMPROVING BLEACHABILITY AND BRIGHTNESS OF WHEAT STRAW CHEMOMECHANICAL PULP%木聚糖酶预处理对麦草化学机械浆可漂性及白度的改善

    Institute of Scientific and Technical Information of China (English)

    洪枫; 刘明山; 房桂干; 沈兆邦

    2001-01-01

    Xylanase from Trichoderma ressei Rut C-30 with corncob meal ascarbon source was prepared and improvement of bleachability and brightness of wheat straw CMP by xylanase pretreatment were investigated. The results indicated that the activity of xylanase was up to 38.34IU/mL with 18g/L(oven dry weight)corncob as the substrate. The xylanase treatment was beneficial to improving the bleachability of wheat straw CMP, enhancing hydrogen peroxide bleaching, increasing the brightness effectively and decreasing the consumption of bleaching agent. The research showed that 50% hydrogen peroxide was saved after enzymic pretreatment when wheat straw CMP was bleached to the same brightness with one-stage H2O2. Furthermore if wheat straw CMP was bleached with two-stage high consistence hydrogen peroxide after enzymatic pretreatment, namely XP3P3(total H2O2 6%)bleaching sequence, the brightness could be over 60%(ISO).%探讨了以玉米芯为碳源制备木聚糖酶及麦草化学机械浆经该木聚糖酶预处理后可漂性和白度的改善效果。结果表明,直接以玉米芯为底物、里氏木霉为菌种产酶效果较好,当底物浓度为18g/L时,木聚糖酶活力可达38.34IU/mL。木聚糖酶预处理有利于改善麦草化机浆的可漂性,促进其过氧化氢漂白,有效提高漂白浆白度,降低漂剂消耗。研究表明,当经单段H2O2漂至相同白度时,木聚糖酶预处理后可节约50%的H2O2用量。若麦草CMP酶处理后采用高浓两段过氧化氢漂白,即XP3P3漂序(H2O2总量为6%)时,白度可达60%(ISO)以上。

  8. Studies on solid state fermentation of xylanase for cellulosic ethanol%纤维素乙醇木聚糖酶的固体发酵工艺研究

    Institute of Scientific and Technical Information of China (English)

    杨付伟; 王林风; 任建伟; 赵子高; 程远超

    2011-01-01

    该研究立足于河南天冠企业集团纤维素乙醇项目,以酶解糖化工艺对木聚糖酶的需求为出发点,利用黑曲霉X06作为产酶菌株,采用固体发酵工艺,通过正交设计试验,优化了培养基配方和发酵控制工艺,最优方案:麸皮:玉米芯=6:4、硝酸铵4%、尿素1%、磷酸二氢钾0.4%、硫酸镁0.2%、初始含水量65%、初始pH=4.0、温度28℃、环境相对湿度70%、72 h酶活达到10096.74 IU/g.这一方案在生产中得到进一步放大和优化,所生产的固体木聚糖酶应用在秸秆酶解工艺中,酶解液中木糖含量提高了66.9%.%Based on the needs of xylanase in the cellulosic ethanol project of Henan Tianguan Group Co., Ltd., Using Aspergillus niger X06 as xylanase-producing strain, through orthogonal experiment, the optimal solution of solid state fermentation was obtained as follows: the wheat bran to corn cob ratio is 6:4,the NH4NO3 content is 4%, the CO(NH2)2 content is 1%, the KH2PO4 content is 0.4%, the MgSO4·TH2O content is 0.2%, the initial moisture content is 65%, the initial pH value is 4.0, the incubation temperature is 28 ℃, the relative humidity of the environment is 70%. The activity of xylanase could reach 10 096.74 IU/g in 72 h. This program has been amplified and further optimized in large-scale production. The production of solid xylanase has been used in straw hydrolysis process, and the xylose content increased by 66.9%.

  9. Effects of cellulase and xylanase enzymes mixed with increasing doses ofSalix babylonicaextract onin vitrorumengas production kinetics of a mixture of corn silage with concentrate

    Institute of Scientific and Technical Information of China (English)

    Abdelfattah Z M Salem; German Buenda-Rodrguez; Mona M M Elghandour; Mara A Mariezcurrena Berasain; Francisco J Pea Jimnez; Alberto B Pliego; Juan C V Chagoyn; Mara A Cerrillo; Miguel A Rodrguez

    2015-01-01

    Anin vitro gas production (GP) technique was used to investigate the effects of combining different doses ofSalix babylonicaextract (SB) with exogenous ifbrolytic enzymes (EZ) based on xylanase (X) and celulase (C), or their mixture (XC; 1:1 v/v) onin vitrofermentation characteristics of a total mixed ration of corn silage and concentrate mixture (50:50, w/w)as substrate. Four levels of SB (0, 0.6, 1.2 and 1.8 mL g–1 dry matter (DM))andfour supplemental styles of EZ (1 µL g–1 DM; control (no enzymes), X, C and XC (1:1, v/v) were used in a 4×4 factorial arrangement.In vitro GP (mL g–1 DM) were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then ifltered to determine dry matter degradability (DMD). Fermentation parameters, such as the 24 h gas yield (GY24),in vitro organic matter digestibility (OMD), metabolizable energy (ME), short chain fatty acid concentrations (SCFA), and microbial crude protein production (MCP) were also estimated. Results indicated that there was a SB´EZ interaction (P0.05) on OMD, pH, ME, GY24, SCFA and MP. The combination of SB with EZ increased (P<0.001) OMD, ME, SCFA, PF72 and GP24, whereas there was no impact on pH. It could be concluded that addition of SB extract, C, and X effectively improved thein vitro rumen fermentation, and the combination of enzyme with SB extract at the level of 1.2 mL g–1 was more effective than the other treatments.

  10. Scientific Opinion on the safety and efficacy of Hostazym X (endo-1,4-beta-xylanase as a feed additive for poultry, piglets and pigs for fattening

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-02-01

    Full Text Available Hostazym X is an enzyme preparation of xylanase produced by a non-genetically modified strain of Trichoderma citrinoviride. The fermentation product showed negative results in a bacterial reverse mutation assay. The results of an in vitro chromosomal aberration test and of an in vivo comet assay indicate the presence of genotoxic activity in the product. Although the tolerance studies provided in target species did not indicate any adverse effect of the additive, the FEEDAP Panel, taking into account the genotoxic hazard from the product, cannot conclude on the safety of the additive for the target species. The results obtained in a subchronic rat study did not indicate any concerns for consumer safety. However, owing to the lack of information on the nature and fate of potentially genotoxic material in food derived from animals receiving the additive, the FEEDAP Panel cannot conclude on the safety of the additive for the consumer. The product should be considered a potential skin and eye irritant, and a potential skin and respiratory sensitiser. Owing to the presence of genotoxic activity in the product, any level of exposure to the additive is considered hazardous. No risks to the environment are expected to result from the use of the additive in feed, and, therefore, no further environmental risk assessment is required. Based on the results obtained in the efficacy studies, the FEEDAP Panel concludes that the additive has the potential to be efficacious in turkeys for fattening at the dose of 1 050 EPU/kg feed and in chickens for fattening, laying hens, piglets (weaned and pigs for fattening at the dose of 1 500 EPU/kg feed. Conclusions on the efficacy can be extrapolated to minor poultry species.

  11. The critical role of partially exposed N-terminal valine residue in stabilizing GH10 xylanase from Bacillus sp.NG-27 under poly-extreme conditions.

    Directory of Open Access Journals (Sweden)

    Amit Bhardwaj

    Full Text Available BACKGROUND: Understanding the mechanisms that govern protein stability under poly-extreme conditions continues to be a major challenge. Xylanase (BSX from Bacillus sp. NG-27, which has a TIM-barrel structure, shows optimum activity at high temperature and alkaline pH, and is resistant to denaturation by SDS and degradation by proteinase K. A comparative circular dichroism analysis was performed on native BSX and a recombinant BSX (R-BSX with just one additional methionine resulting from the start codon. The results of this analysis revealed the role of the partially exposed N-terminus in the unfolding of BSX in response to an increase in temperature. METHODOLOGY: We investigated the poly-extremophilicity of BSX to deduce the structural features responsible for its stability under one set of conditions, in order to gain information about its stability in other extreme conditions. To systematically address the role of the partially exposed N-terminus in BSX stability, a series of mutants was generated in which the first hydrophobic residue, valine (Val1, was either deleted or substituted with various amino acids. Each mutant was subsequently analyzed for its thermal, SDS and proteinase K stability in comparison to native BSX. CONCLUSIONS: A single conversion of Val1 to glycine (Gly changed R-BSX from being thermo- and alkali- stable and proteinase K and SDS resistant, to being thermolabile and proteinase K-, alkali- and SDS- sensitive. This result provided insight into the structure-function relationships of BSX under poly-extreme conditions. Molecular, biochemical and structural data revealed that the poly-extremophilicity of BSX is governed by a partially exposed N-terminus through hydrophobic interactions. Such hitherto unidentified N-terminal hydrophobic interactions may play a similar role in other proteins, especially those with TIM-barrel structures. The results of the present study are therefore of major significance for protein folding

  12. Effects of wheat cultivar, metabolizable energy level, and xylanase supplementation to laying hens diet on performance, egg quality traits, and selected blood parameters

    Directory of Open Access Journals (Sweden)

    Masoud Mirzaee

    2014-10-01

    Full Text Available A 2 x 2 x 2 factorial arrangement of treatments was conducted to evaluate the effects of two dietary apparent metabolizable energy (AME levels (2,720 and 2,580 kcal kg-1 diet and enzyme (0 and 0.3 g kg-1 diet, Grindazym® GP 15,000 with mostly xylanase activity supplementation on the performance of laying hens fed diets based on two wheat cultivars (Marvdasht and Sardari. Experimental diets were formulated to have a constant energy to protein ratio and were fed to 65-wk-old Lohmann LSL-Lite laying hens for 7 wk. The lower level of AME reduced egg production and egg mass (p<0.05 and increased feed conversion ratio (p<0.05. Enzyme addition increased feed intake of the birds fed a diet with Sardari cultivar (p<0.05 but had no effect on feed intake of the birds fed a diet with Marvdasht cultivar (p>0.05. Nevertheless, birds receiving diets based on Marvdasht cultivar had higher feed intake and egg mass than that of those receiving diets based on Sardari cultivar (p<0.05. The birds fed diets based on Marvdasht cultivar produced less undesired eggs and had better yolk color as compared with the birds fed diets based on Sardari cultivar (p<0.05. The serum concentration of glucose increased by enzyme supplementation when birds receiving lower AME level (p<0.05. These results indicate that enzyme supplementation may have a positive effect on the feed intake of laying hens when fed on wheat-based diets; however, this effect is cultivar dependent and does not necessarily mean that enzyme supplementation always benefit production.

  13. Energetic values and performace of broilers feeding sorghum and soybean meal based diets supplemented with B-glucanase and B-xylanase

    Directory of Open Access Journals (Sweden)

    Evandro de Abreu Fernandes

    2016-04-01

    Full Text Available Grains, brans, and vegetable meals may contain non-starch polysaccharides (NSP, which increases viscosity in the gastrointestinal tract (GIT and interfere with the digestion and absorption of nutrients. This study aimed to evaluate the performance and determine the metabolizable energy of a sorghum-based broiler diet with and without the supplementation of an enzymatic complex. The experiments were conducted in a completely randomized design with 1200 chickens, using sorghum-based feed with and without the addition of 50 g of enzyme-CCE complex (?-glucanase and ?-xylanase, and with two levels of metabolizable energy (ME kg-1: ME; ME + CCE; reduced ME (-50 kcal kg-1; and reduced ME + CCE. The data were subjected to an analysis of variance and the means were compared using a Tukey’s test at the 5% significance level. At 42 and 47 days of age, the living weight of the birds fed with the reduced ME was low, while birds fed with reduced ME + CCE had the same weight as those fed with other energy diets (ME and ME + CCE. Feed conversion was poorest at 47 days of age for the birds on reduced ME diet. In the metabolic test (with fattening diets to determine AME and AMEn, the reduced ME diet had the lowest result, confirming the effect of the addition of enzymes. The addition of CCE to sorghum-based diets provides enough enzymatic activity to increase the metabolizable energy of the diet (50 kcal of AME and influence the growth performance of broilers at the slaughtering age.

  14. Scientific Opinion on the safety and efficacy of Feedlyve AXC (endo-1,4-beta-xylanase as a feed additive for turkeys

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed

    2012-07-01

    Full Text Available

    Feedlyve AXC is an enzyme preparation containing an endo-1,4-beta-xylanase produced by a non-genetically modified strain of Trichoderma koningii. The additive is intended for use in turkeys and is presented in several forms. A tolerance study performed with a 100-fold of the maximum recommended dose (100 AXC/kg feed showed no adverse effects in turkeys for fattening. Therefore, it is concluded that Feedlyve AXC is safe for turkeys for fattening at the maximum recommended dose. This conclusion is extended to turkeys reared for breeding. The results of two genotoxicity in vitro studies and a sub-chronic oral toxicity study did not indicate any concern for consumer safety arising from the use of the additive in feed for turkeys. Feedlyve AXC 6000P was negative in dermal and eye irritation tests in the rabbit. No data on the skin/eye irritation potential of the BRUTE formulation is available. Therefore, the FEEDAP Panel considers it prudent to treat this formulation as a potential skin/eye irritant. No skin sensitization and no acute respiratory toxicity were observed in appropriate tests using the BRUTE formulation. Due to the proteinaceous nature of the compound the additive is to be considered as a potential respiratory sensitiser. The active substance of Feedlyve AXC is a protein and as such will be degraded/inactivated during the passage through the digestive tract of animals. Therefore, no risks for the environment are expected and no further environmental risk assessment is required. A total of three efficacy studies in turkeys for fattening were provided. Results showed that the additive has the potential to be efficacious when added to diets for turkeys for fattening at a minimum dose of 75 AXC/kg complete feed. This conclusion can be extended to turkeys reared for breeding.

  15. 重组多功能木聚糖酶酶解条件的优化%Optimization of enzymatic hydrolysis of recombinant multi-functional xylanase

    Institute of Scientific and Technical Information of China (English)

    赵力超; 王燕; 刘晓娟; 林俊芳

    2014-01-01

    重组多功能木聚糖酶(recombinant multi-functional xylanase,RMFXase)是以草菇为表达载体,具有多种酶活力的新型酶。为揭示该酶与底物的作用规律,同时为转基因酶的应用提供基础数据,该文利用重组多功能木聚糖酶水解南方特色的甘蔗加工废弃物生产低聚木糖,通过响应面法建立以重组多功能木聚糖酶质量浓度、底物质量浓度和酶解时间为控制因素的反应动力学方程组,从而推导得到酶解最佳工艺参数。试验并通过高效液相色谱法法,监测反应过程中产物的动态变化,分析产物的生成规律。结果表明,通过响应面法推导出符合连续式酶解反应器的最佳酶解工艺参数为:加酶量900 U/mL、底物质量浓度110 mg/mL、反应时间80 min。该条件下酶解木聚糖含量为54.7%的蔗渣半纤维素,得到的低聚木糖DP值达到3,酶解率达到23.94%。酶解过程中重组多功能木聚糖酶表现出高内切-β-1,4-木聚糖活力,优先降解大分子木聚糖,后期产物主要以木二糖和木三糖为主,且底物纯度越高,底物利用率越高。%The utilization of microorganisms or their enzymes may be the most promising method to produce Xylo-oligosaccharides (XOs) from agricultural wastes because of fewer undesirable by-products and fewer monosaccharides produced, and no special equipments required. Industrial-scale production of XOs using bioconversion requires low-cost substrates with a high xylan content, low lignin content and enzymes with high activity, process stability and β-1,4-xylosidic bond specificity. In the current study, bagasse, by-products of sugarcane production, was used as substrates for XOs production. And hydrolysis of bagasse hemicellulose was carried out with a recombinant multi-functional xylanase (RMFXase). RMFXase is a novel enzyme produced from genetically engineered straw mushroom (Volvariella volvacea) strain, which has exo

  16. Scientific Opinion on the efficacy of Natugrain® TS/TS L (endo-1,4-beta-xylanase and endo-1,4-beta-glucanase as a feed additive for laying hens

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-06-01

    Full Text Available Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP was asked to deliver a scientific opinion on the efficacy of Natugrain® TS/TS L in laying hens. This feed additive contains endo-1,4-beta-xylanase and endo-1,4-beta-glucanase, produced by two genetically modified strains of Aspergillus niger. The product is available in solid (Natugrain® TS and liquid (Natugrain® TS L forms. This additive is authorised for use in weaned piglets and pigs for fattening, poultry species and ornamental birds. The applicant is now seeking a modification of the terms of the authorisation to reduce the recommended dose in laying hens from 560 thermostable xylanase units (TXU and 250 thermostable glucanase units (TGU per kg feed to 280 TXU and 125 TGU per kg feed. The FEEDAP Panel assumes that the two formulations of the additive are equivalent in terms of efficacy. A total of three trials were provided. Based on the results obtained, the Panel concludes that Natugrain® TS has the potential to be efficacious in laying hens at the dose of 280 TXU and 125 TGU per kg feed.

  17. Scientific Opinion on the safety and efficacy of Rovabio® Excel (endo-1,3(4-beta-glucanase and endo-1,4-beta-xylanase as a feed additive for lactating sows

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-06-01

    Full Text Available Rovabio® Excel is a preparation of endo-1,3(4-beta-glucanase and endo-1,4-beta-xylanase that is intended to be used as a feed additive for lactating sows, at a dose of 1 500 glucanase U and 1 100 xylanase U/kg feed, in order to minimise the mobilisation of body reserves of sows during lactation. The European Food Safety Authority issued an opinion on the safety and efficacy of Rovabio® Excel as a feed additive for chickens and turkeys for fattening, laying hens, piglets (weaned and pigs for fattening, ducks, guinea fowl, quails, geese, pheasants and pigeons. The full description of the formulations, manufacturing processes, purity, stability and homogeneity of the product is given in that assessment. The FEEDAP Panel considers that the safety aspects, other than for the new target species, are covered in the previous assessment and would not be affected by the extension of use requested. The results of a tolerance study showed that 200-fold the recommended dose was tolerated well by the sows when offered for a period of seven weeks, including gestation and lactation. Therefore, the Panel concludes that the recommended dose is safe in lactating sows. The Panel cannot conclude on the efficacy of Rovabio® Excel from the available efficacy data.

  18. Production of Cellulases, Xylanase, Pectinase, alpha-amylase and Protease Enzymes Cocktail by Bacillus spp. and Their Mixed Cultures with Candida tropicalis and Rhodotorula glutinis under Solid State Fermentation

    International Nuclear Information System (INIS)

    A group of twelve locally isolated Bacillus species, B.megaterium (MAI and MA II), B.licheniformis (MLI and ML II); B. circulans, B. stearothermophilis, B.cereus, B.sphaericus, B. pumilus, B. laterosporus, B. coagulans and B. pantothenticus, were examined for the production of cellulases, xylanase, pectinase, alpha-amylase and protease enzymes cocktail on wheat bran under solid state fermentation (SSF). All species were found to be potent hydrolyzing enzymes producers and the superior producing species were B. megaterium MAI and B. licheniformis. On the other hand, both of them still produced highest enzyme titres when mixed with Candida tropicalis or Rhodotorula glutinis, yeast strains. The two superior bacterial strains produced the highest enzymatic activities when coculturing with C. tropicalis compared with coculturing with R. glutinis only or with both C. tropicalis and R. glutinis in combination. The inferior activities of cocultures (B. megaterinm MAI and R. glutinis) were enhanced in carboxymethyl cellulase (CMCase), filter paper cellulase (FPase), avecilase, xylanase, pectinase, -amylase and protease by gamma irradiation at dose 1.0 kGy with percent increase 8 %, 20 %, 10 %, 4 %, 31 %, 22 % and 34 %, respectively as compared with un-irradiated cocultures

  19. Cloning and Sequencing of Xylanase cDNA from Volvariella volvacea Using Conserved Sequences in Cellulose-Binding Domain%利用真菌纤维素结合域(CBD)保守性序列进行草菇木聚糖酶cDNA的克隆

    Institute of Scientific and Technical Information of China (English)

    丁少军; J.A.BUSWELL

    2004-01-01

    Cellulose-binding domains (CBDs) are present in the majority of fungal cellulases and hemicellulases. Based on the conserved region of CBDs, degenerate primers were designed and used to amplify the 5′-end cDNA fragment of xylanase from Volvariella volvacea by 5′-RACE. Gene specific primer was then designed based on extreme region of 5′-end cDNA fragment and used to amplify the full length cDNA of xylanase. The cDNA of xynl was 1287 bp in length, including 3′and 5′-non-coding region. The xynl cDNA contained an ORF of 1101 bp encoding 367 amino acids, in which there was a putative signal peptide with 19 amino acids. Alignment of the deduced amino acid sequence of xynl with other xylanases showed that the homology with family-10 xylanases from Agaricus bisporus xyll, AspergiUus sojae xynl, Aspergillus kawachii xynA, Fusarium oxysporumf, sp xyl3 was 64% ,55% ,52% ,55% , respectively.

  20. 戊聚糖及木聚糖酶对肉雏鸡器官发育的影响%Effects of Pentosans and Xylanase Supplementation on Organ Development of Broiler Chick

    Institute of Scientific and Technical Information of China (English)

    盛清凯; 赵红波; 黄保华

    2013-01-01

    The experiment was conducted to study effects of water-soluble pentosan (WSP),alkai-extractable pentosan (AEP) and xylanane on the organ development of broiler chicks fed on the corn-soybean meal diets and probe into the difference of their mechanisms.Three hundred and fifty 1-day-old Avain broiler chicks were randomly divided into 7 treatments with 5 replicates and 10 broilers in each replicates,fed corn-soybean meal basal diet and experimental diets supplemented with 50 mg/kg WSP,100 mg/kg.WSP,50 mg/kg AEP,100 mg/kg AEP,3 mg/kg xylanase,6 mg/kg xylanase,respectively.The experiment lasted for 15 days.The results showed that compared with control group,WSP and AEP and xylanase increased significantly body weight,the weight of bursa of fabricius and gizzard and glandular stomach,the length of gut (P <0.05),but had no significant effect on lactobacillus and streptococcus and salmonella and coliform in recta chyme.WSP and AEP raised the viscosity and the xylanase decreased the viscosity with the two chime viscosities extremely significant different (P <0.01).50 mg/kg WSP supplementation promoted the development of broiler chicks best.The result indicated WSP and AEP had different mechanism with xylanase in promoting the organ development of broiler chicks.%研究水溶戊聚糖(WSP)、碱溶戊聚糖(AEP)和木聚糖酶对玉米-豆粕型日粮肉雏鸡器官发育的影响,探讨三者作用差异.350只1日龄肉雏鸡随机分为7组,每组5个重复,每重复10只鸡,每组分别饲喂玉米-豆粕基础日粮和外加50 mg/kg WSP、100mg/kg WSP、50 mg/kg AEP、100 mg/kg AEP、3 mg/kg木聚糖酶、6mg/kg木聚糖酶的试验日粮.试验期15日.结果表明,和对照组相比,WSP、AEP和木聚糖酶显著增加了肉雏鸡体重、法氏囊、腺胃和肌胃重量以及肠道长度(P<0.05),对直肠中乳酸菌、链球菌、沙门氏菌和大肠杆菌无显著影响.WSP和AEP增加了食糜粘度,而木聚糖酶降低了食糜粘度,二者

  1. 产木聚糖酶海洋微生物的筛选与诱变育种%Screening and breeding by induced mutation of xylanase-producing marine microorganism

    Institute of Scientific and Technical Information of China (English)

    黄小云; 林娟; 林小洪; 王国增; 叶秀云

    2015-01-01

    With self-made xylan as the only carbon source of primary screening medium , totally 60 strains which showed transparent zones and different morphology were screened from different marine samples .The shake flask fermentation results showed that 38 strains had xylanase-producing capabil-ities and strain B659 had the highest xylanase activity of 525.3 U· mL-1 .Via morphological charac-teristics and 16S rDNA sequence analysis , strain B659 was identified as Bacillus.The stable mutant strain G3-17 with 13.9%enhancement of xylanase activity was screened from the UV mutagenesis of strain B659.A stable mutant strain W1-40 with 11.6% xylanase activity increase was obtained by microwave mutation and screening from strain G 3-17.In 72 h fermentation of strain B659 and strain W1-40, the xylanase activity of latter (645.2 U· mL-1 ) achieved 24.6%elevation than the former (517.9 U· mL-1).%以自制木聚糖为初筛培养基的唯一碳源,从多个海洋来源样品中一共筛到60株有透明圈且形态各异的菌株,摇瓶发酵结果显示,38株具有产木聚糖酶能力,其中B659菌株产酶能力最高,酶活力为525.3 U· mL-1.结合B659菌株的形态特征和16S rDNA序列分析鉴定该菌株属于Bacillus属.对B659菌株进行紫外诱变,筛选得到酶活提高13.9%且稳定遗传的突变菌株G3-17;对G3-17菌株进一步进行微波诱变得到酶活较G3-17菌株高出11.6%且稳定遗传的突变菌株W1-40.对B659菌株和W1-40突变菌株进行发酵试验,72 h时W1-40菌株的酶活力达到645.2 U· mL-1,比B659菌株(517.9 U· mL-1)提高24.6%.

  2. FERROFLUIDS INFLUENCE ON DEHYDROGENASES ACTIVITY IN CELLULOLYTIC FUNGUS CHAETOMIUM GLOBOSUM

    Directory of Open Access Journals (Sweden)

    Alexandru Manoliu

    2003-08-01

    Different results were noticed for different ferrofluids concentrations: 20, 40, 60, 80 and 100 μl/L. Inhibitory or stimulatory ferrofluids effect was obtained depending on the nature of the investigated enzyme.

  3. Purification and characterization of a new Xylanase from Humicola grisea var. Thermoidea Produção, purificação e caracterização de uma nova Xilanase de Humicola grisea var. Thermoidea

    Directory of Open Access Journals (Sweden)

    Severino de Albuquerque Lucena-Neto

    2004-06-01

    Full Text Available The thermophilic fungus Humicola grisea var. thermoidea secretes extracellular xylanase when grown on solid and in liquid media containing wheat bran and banana plant residue as substrates, respectively. At 55ºC, xylanase from the culture filtrate of H. grisea var. thermoidea grown on banana stalk retained 50% of its activity after 28 h of incubation. A xylanase (X2 was isolated from solid state cultures with wheat bran as the carbon source. It was purified to apparent homogeneity by ultrafiltration followed by ion-exchange and hydrophobic interaction chromatography on DEAE-Sepharose and Phenyl-Sepharose resins, respectively. The enzyme had an apparent molecular weight of 29 kDa, as determined by SDS-PAGE. The purified enzyme was most active at pH and temperature ranges of 4.5-6.5 and 55-60ºC, respectively. In addition, X2 showed thermostability at 60ºC with a half-life of approx. 5.5 h. The apparent Km values, using soluble and insoluble arabinoxylans as substrates, were 10.87 and 11.20 mg/ml, respectively.O fungo termofílico Humicola grisea var. secreta xilanase extracelular quando cultivado em meios sólidos e líquidos contendo farelo de trigo e engaço de bananeira como substratos, respectivamente. À temperatura de 55ºC, xilanase do filtrado de meio de cultura de H. grisea var. thermoidea cultivado em engaço de bananeira reteve 50% de sua atividade após 28 de incubação. Uma xilanase (X2 foi isolada de culturas de estado sólido contendo farelo de trigo como fonte de carbono. X2 foi purificada por ultrafiltração, seguido por cromatografias de interação hidrofóbica e troca iônica em resinas de Phenyl-Sepharose e DEAE-Sepharose, respectivamente. A enzima apresentou peso molecular de 29 kDa, como determinado por SDS-PAGE. A enzima purificada foi mais ativa em intervalos de pH e temperatura de 4,5-6,5 and 55-60ºC, respectivamente. Além disso, X2 mostrou termoestabilidade a 60ºC com meia vida de aproximadamente 5,5 h. Os

  4. 金针菇菌糠中木聚糖酶的分离纯化及其酶学性质研究%Purification and Properties of Xylanase from Spent Mushroom Compost of Flammulina velutipes

    Institute of Scientific and Technical Information of China (English)

    杨云龙; 黄彩梅; 白植成; 胡开辉

    2015-01-01

    废弃食用菌栽培料( SMC)中含有一定活性的木聚糖酶,作者以金针菇菌糠为材料,采用盐析、Sephadex G-100凝胶层析和DEAE C-52离子交换层析等技术,对SMC中的木聚糖酶进行分离和纯化,并进行酶学性质研究。结果表明,该酶经SDS-PAGE电泳鉴定为电泳纯,分子量为37.8 KDa,酶比活力达到946.67 U/mg,纯化倍数为12.74;酶的最适温度和pH分别为50℃和pH 6.0,Fe2+、Zn2+对木聚糖酶有激活作用,Ca2+、Mn2+、K+有促进作用,Mg2+、Cu2+、Fe3+有抑制作用,反应动力学参数Vmax和Km 分别为15.43μg/mL/min、9.61 mg/mL。%Xylanase produced by Spent Mushroom Compost was isolated and purified by ammonium sulfate salting-out,Sephadex G⁃100 column chromatography and DEAE C⁃52 anion chromatography exchange,and its enzymatic properties were studied.The results illustrated that it exhibited a single band by the SDS⁃PAGE,and the molecular weight was estimated as 37. 8 KDa. The purification made the specific activity as high as 946.67 U/mg and purification multiple reached 12.74.The optimal temperature and pH value for activity were 50 ℃ and pH 6.0 respectively,which had a certain acid and alkali resistance and high⁃temperature⁃resisting.Xy⁃lanase obtained in this study was activated by Fe2+and Zn2+;promoted by Mn2+,K+and Ca2+;while inhibited by Mg2+,Cu2+ and Fe3+.The Vmax and Km values of the xylanase for xylan were 15.43μg/mL/min and 9.61 mg/mL, respectively.The study suggests that this xylanase has a good potential to be a cold⁃stable xylanase in paper man⁃ufacturing and feed industries.

  5. Production and properties of the cellulase-free xylanase from Thermomyces lanuginosus IOC-4145 Produção e propriedades de xilanase livre de celulase de Thermomyces lanuginosus IOC-4145

    Directory of Open Access Journals (Sweden)

    Mônica Caramez Triches Damaso

    2002-12-01

    Full Text Available In recent years, xylanases have expanded their use in many processing industries, such as pulp and paper, food and textile. Thermomyces lanuginosus IOC-4145 was able to produce a very high level of cellulase-free xylanase in shaken cultures using corncob as substrate (500 U/mL. An optimization of the medium composition in submerged fermentation was carried out aiming at a low cost medium composition for enzyme production. Statistical experiment design was employed for this purpose, pointing out corncob as the most important parameter, which affects enzyme production. Additionally, the influence of several chemicals on xylanase activity was investigated in the crude extract. A slight stimulation of the enzyme (5-15% was achieved with NaCl and urea, both at 3 and 5 mM of concentration. On the other hand, dithiothreitol and beta-mercaptoethanol at a molarity of 5mM have caused a strong stimulation of the enzyme (40-53%. The crude xylanase displayed appreciable thermostability, retaining almost 50% of activity during 24 hours of incubation at 50ºC; about 50% of activity was present at 60ºC even after 4 hours of incubation. The enzyme also exhibited good storage stability at -20ºC without any stabilizing agent.Nos últimos anos tem crescido o uso de xilanases em muitas indústrias, tais como polpa e papel, alimentos e têxtil. Thermomyces lanuginosus IOC-4145 foi capaz de produzir um alto nível de xilanase livre de celulase em culturas agitadas usando sabugo de milho como substrato (500 U/mL. Procedeu-se, inicialmente, à otimização da composição do meio de produção em fermentação submersa, com o intuito de alcançar uma composição de meio de produção de baixo custo para produção da enzima. Para este propósito, utilizou-se planejamento estatístico de experimentos. O sabugo de milho revelou-se como a mais importante variável que afeta a produção enzimática. Adicionalmente, a influência de vários reagentes na atividade xilan

  6. Coexpression of β-mannanase Gene and Xylanase Gene in Pichia pastoris%β-甘露聚糖酶基因和木聚糖酶基因在毕赤母中的共表达

    Institute of Scientific and Technical Information of China (English)

    李剑芳; 赵顺阁; 邬敏辰; 张慧敏; 魏喜换

    2012-01-01

    β -mannanase and xylanase are extensively used in food industry. Synergistic action between the two enzymes is obersved to effectively improve digestibility of the hemicelluloses of food material. In order to coexpress β -mannanase gene and xylanase gene in Pichia pastoris, pPIC9K-xyn Ⅱ was linearized with Sal /and transformed into GSll5/Anman5A by electroporation. GS115/A nman5A-xyn Ⅱ with high production of β-mannanase and xylanase was screened by using G418. SDS-PAGE demonstrated two protein bands with apparent molecular weight of about 52 000 and 24 100. One GS115/Anman5A-xyn Ⅱ transformant producing the highest activities of two enzymes in shake flasks was selected and numbered as GSMX2. Subsequently the expression conditions for enzymes production by using GSMX2 were optimized, the optimum expression conditions listede as follows:initial pH 7.0,glycerol concentration 1.5% ,methanol concentration 1.5%, induction for 120 h. Under these conditions, the activities of β-mannanase and xylanase were achieved at 37.1 U/mL and 193.6 U/mL, respectively.%为实现β-甘露聚糖酶基因和木聚糖酶基因在毕赤酵母中的共表达,作者将经SalⅠ线性化的pPIC9K-xynⅡ电转化至工程菌GS115/Anman5A中,经G418浓度梯度筛选后获得能同时高产β-甘露聚糖酶和木聚糖酶的双重重组子GS115/Anman5A-xynⅡ.SDS-PAGE显示目的蛋白的相对分子质量分别约为52 000,24 100.摇瓶发酵筛选出产酶活性最强的转化株,命名为GSM X2,随后对该菌株的表达条件进行初步优化,优化后的表达条件为:诱导时间120 h,培养基起始pH值为7.0,甘油添加量为1.5%,甲醇添加量为1.5%.在此培养条件下,产β-甘露聚糖酶和木聚糖酶的活性分别达到37.1 U/mL和193.6 U/mL.

  7. Scientific opinion on the safety and efficacy of Natugrain® TS (endo-1,4-beta-xylanase and endo-1,4-beta-glucanase as a feed additive for pigs for fattening

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-07-01

    Full Text Available Natugrain® TS is an enzyme preparation that contains endo-1,4-beta-xylanase and endo-1,4-beta-glucanase, produced by two genetically modified strains of Aspergillus niger. This product is currently authorised for use in piglets (weaned, poultry species and ornamental birds as a zootechnical additive under the functional group of digestibility enhancers. The applicant is now seeking for the extension of its use as a zootechnical additive for pigs for fattening at a dose range of 560 to 840 TXU (thermostable xylanase units and 250 to 375 TGU (thermostable glucanase units per kg feed. Since the product has been demonstrated to be  safe in piglets at the maximum recommended dose, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP considers that this conclusion can be extended to pigs for fattening, provided that the same maximum dose applies. In two long-term trials, Natugrain® TS significantly improved the performance of the pigs for fattening at the minimum recommended dose (560 TXU and 250 TGU/kg feed. In a balance trial, the metabolisable energy content of the diet was significantly improved by the addition of Natugrain® TS in feed at the minimum recommended dose. Therefore, the FEEDAP Panel concludes that Natugrain® TS at the minimum recommended dose (560 TXU and 250 TGU/kg feed has the potential to be efficacious in pigs for fattening.

  8. Purification and Properties of Xylanases from Pencillium corylophilum%顶青霉木聚糖酶的纯化与性质

    Institute of Scientific and Technical Information of China (English)

    杨瑞金; 许时婴; 王璋

    2001-01-01

    Three parts of xylanases (Part A, Part B and Part C) wereseparated and purified from a culture filtrate of Pencillium corylophilum No.P-3-31. Part B was further purified to homogeneity and Part C was further purified to almost homogeneity by the same procedures as Part B. The molecular weights of Part B and Part C were estimated to be 24 200 and 48 300 respectively by SDS-PAGE. The optimal pH and temperature of enzymes were 4.0 and 45 ℃ for Part A and Part B, while 5.5 and 50~55 ℃ for Part C. Part C showed a substrate-cross- specificity on hydrolyzing CMC and had an activity of β-xylosidase, but this activity was unable to hydrolyze xylobiose. Part A and Part B did not show the substrate-cross-specificity. Both crude and purified enzymes showed significant differences in their activities to hydrolyze different xylans from different sources. For the crude enzyme, if the activity to birchwood xylan was set as 100%, then those to corncob xylan and bagasse xylan were 143% and 124% respectively.%从顶青霉(Pencilliumcorylophilum)P-3-31培养液中分离到3种木聚糖酶组分,分别称为PartA、PartB和PartC.PartB进一步纯化,经SDS-PAGE鉴定为单带,相对分子质量为24200;PartC进一步纯化,经SDS-PAGE鉴定也是单带,相对分子质量为48300.PartA和PartB的最适反应条件为pH4.0,45℃;PartC的最适反应条件为pH5.5,55℃.PartA和PartB对木聚糖以外的底物不能水解;PartC具有水解CMC的交叉活性和β-木糖苷酶活性,但不能将木二糖水解成木糖.3个纯化酶组分和粗酶对不同来源的木聚糖底物均表现出不同的活性.对于粗酶,若桦木木聚糖为底物的相对酶活为100%,则玉米芯木聚糖为底物的相对酶活为143%,蔗渣木聚糖为底物的相对酶活为124%.

  9. 产耐热木聚糖酶细菌的分离鉴定及酶易错PCR致突变条件优化%Isolation & Identification of a Heat-Resistant Xylanase-Producing Bacterial Strain & Optimization of the Enzyme Error-Prone PCR Mutagenic Conditions

    Institute of Scientific and Technical Information of China (English)

    赵超; 张宁宁; 梅凡; 艾超; 阮灵伟; 黄一帆; 刘斌

    2013-01-01

    从福建省永泰县温泉采集样品中筛选到1株产耐热木聚糖酶嗜热菌株TC-W7,并获得该木聚糖酶基因。在此基础上,采用易错PCR技术在木聚糖酶基因中引入突变,研究Mg2+浓度、Mn2+浓度、dTTP/dCTP浓度等条件对突变率的影响。通过形态特征、生理生化试验及16S rRNA序列相似性比对分析,初步鉴定菌株TC-W7为土壤芽胞杆菌(Geobacillus),菌株TC-W7在最适温度75℃和 pH 8.2条件下,其木聚糖酶活力为215.83 U/mL,Triton X-100和DDT能显著增强该酶的活性。在 Mg2+浓度为20μmol/L,Mn2+浓度为0.80μmol/L,dTTP/dCTP浓度为0.30 mmol/L的致突变条件下,碱基突变率为0.98%。 Geobacillus sp. TC-W7产木聚糖酶具有较好的耐热和耐碱等工业应用特性,对该酶易错PCR致突变条件优化结果,可用于后续木聚糖酶的耐热定向进化。%A heat-resistant xylanase-producing bacterial strain TC-W7 from samples collected in a hot spring in Yong-tai County, Fujian Province was screened and obtained xylanase gene of the strain. Based on these an error-prone PCR ( Ep-PCR) technique was adopted to introduce mutation in the xylanase gene, to study the effects of the concentration such as Mg2+, Mn2+ and dTTP/dCTP and other conditions on the mutation rate. It was initially identified that strain TC-W7 belonged to Geobacillus through morphology features, physiological and biochemical tests as well as 16S rRNA sequence comparative analysis. Under the most suitable temperature 75℃ and pH 8. 2, the activity of xylanase was at 215. 83 U/mL, Triton X-100 and DDT could remarkably increase the activity of xylanase. The base mutation rate was at 0. 98% under the mutagenic conditions of 20. 0 μmol/L Mg2+, 0. 80 μmol/L Mn2+ and 0. 30 mmol/L dTTP/dCTP. The xylanase-producing Geobacillus sp. TC-W7 had a fine heat and alkali resistance and other industry appli-cable features. The results of Ep-PCR mutagenic conditions optimization of the enzyme can be used for

  10. Expression of cold-adapted β-1,3-xylanase as a fusion protein with a ProS2 tag and purification using immobilized metal affinity chromatography with a high concentration of ArgHCl.

    Science.gov (United States)

    Kudou, Motonori; Okazaki, Fumiyoshi; Asai-Nakashima, Nanami; Ogino, Chiaki; Kondo, Akihiko

    2015-01-01

    Cold-adapted β-1,3-xylanase (P.t.Xyn26A) from the psychrotrophic bacterium, Psychroflexus torquis, was expressed as a fusion protein with tandem repeats of the N-terminal domain of Protein S from Myxocuccus xanthus (ProS2) in Escherichia coli. After cell lysis in phosphate buffer, most of the ProS2-P.t.Xyn26A was located in the insoluble fraction and aggregated during purification. Arginine hydrochloride (ArgHCl) efficiently solubilized the ProS2-P.t.Xyn26A. The solubilized ProS2-P.t.Xyn26A was purified using immobilized metal affinity chromatography (IMAC) with 500 mM ArgHCl. After cleavage of ProS2-P.t.Xyn26A by human rhinovirus 3C protease, we confirmed that recombinant P.t.Xyn26A maintained its native fold. This is the first report of the expression of a cold-adapted enzyme fused with a ProS2 tag under IMAC purification using a high concentration of ArgHCl. These insights into the expression and purification should be useful during the handling of cold-adapted enzymes. PMID:25214227

  11. Xylanase production with xylan rich lignocellulosic wastes by a local soil isolate of Trichoderma viride Produção de xilanase com resíduos lignocelulósicos ricos em xilana por uma cepa local de Trichoderma viride isolada de solo

    Directory of Open Access Journals (Sweden)

    Meenakshi Goyal

    2008-09-01

    Full Text Available In the present study, cultural and nutritional conditions for enhanced production of xylanase by a local soil isolate of Trichoderma viride, using various lignocellulosic substrates in submerged culture fermentation have been optimized. Of the lignocellulosics used, maize straw was the best inducer followed by jowar straw for xylanase production. The highest activity achieved was between 14 to 17 days of fermentation. A continuous increase in xylanase production was observed with increasing level of lignocellulosics in the medium and highest activity was observed with maize straw at 5% level. Xylanase production with higher levels of lignocellulosics (3 to 5% of maize, jowar and barseem was found to be higher as compared to that with commercial xylan as carbon source. Sodium nitrate was the best nitrogen source among the six sources used. Maximum xylanase production was achieved with initial medium pH of 3.5-4.0 and incubation temperature of 25ºC.The enzyme preparation was effective in bringing about saccharification of different lignocellulosics. The xylanase production could be further improved by using alkali treated straw as carbon source.Neste estudo, otimizou-se as condições culturais e nutricionais para produção aumentada de xilanase por uma cepa local de Trichoderma viride isolada de solo, empregando-se vários substratos lignocelulósicos, em fermentação submersa. Entre os substratos utilizados, o melhor indutor de produção de xilanase foi palha de milho, seguido de palha de sorgo. A atividade mais alta foi obtida entre 14 e 17 dias de fermentação. Com palha de milho observou-se um aumento contínuo na produção de xilanase com o aumento da concentração dos substratos lignocelulósicos no meio, sendo que a melhor atividade foi obtida com 5% de palha de milho. A produção de xilanase com níveis mais altos de (3 a 5% de milho, sorgo e forragem verde (barseem foi mais levada do que com xilana comercial como fonte de carbono

  12. 产木聚糖酶的沿海红树林真菌筛选及其培养与酶活测定条件优化%Survey of coastal mangrove fungi for xylanase production and optimized culture and assay conditions

    Institute of Scientific and Technical Information of China (English)

    袁康培; 关利平; 冯明光

    2005-01-01

    从香港海岸红树林分离到的77株真菌中有34株可产生木聚糖酶,从中选出CY2809(Staganospora sp.)、CY4786和CY5040等3菌株与已知陆生产酶菌株HU5048(Aspergillus awamori)进行产木聚糖酶的比较研究.根据培养液中菌丝生物量、木聚糖酶活力和木糖等价还原糖含量等指标的测定,菌株CY4786在起始pH 7.8的木聚糖-酵母膏-海盐液体培养基中25℃下震荡(100r/min)培养7d产酶最佳;粗酶液在50q℃和pH 4.6的优化条件下进行测定,木聚糖酶活力达到1.07×104U/mL.结果表明,红树林真菌起着半纤维素降解者的作用,沿海红树林环境中存在着可资利用的木聚糖酶产生菌.作者讨论了利用发酵液中木糖等价还原糖含量的动态变化作为快速筛选产木聚糖酶菌株的指标的可能性.%Xylanase activity was detected among 34 of 77 fungal isolates derived from decaying wood, debris and soil samples collected in coastal mangrove environment of Hong Kong. Of those, three isolates CY2809 (Staganospora sp. ), CY4786 and CY5040 were chosen for comparison of xylanase production in parallel to HU5048 ( Aspergillus awamori ), a terrestrial, highly productive isolate. Based on the assessment of mycelial biomass, xylanase activity and content of xylose-equivalent reducing sugars in their liquid cultures, the isolate CY4786 was best for xylanase production in a basal medium containing birchwood xylan (10.0 g/L)as a sole carbon source, yeast extract (2.5 g/L) and sea salts (15.0 g/L) with initial pH 7.8. When assayed at the optimized regime of 50℃ and pH 4.6, the activity of xylanase produced by CY4786 in 7d liquid culture at 25℃ reached 1.07 × 104 unit/mL. The results indicate that the mangrove fungi act as hemicellulose decomposers in the mangrove environment where highly xylanaseproductive isolates can be searched for exploitation. A discussion is given on the possible use of the content of xylose-equivalent reducing sugars as an index to

  13. Scientific opinion on the safety and efficacy of Ronozyme WX (endo-1,4-beta-xylanase as a feed additive for poultry, piglets (weaned and pigs for fattening

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed

    2012-07-01

    Full Text Available

    Ronozyme WX is a preparation of endo-1,4-beta-xylanase produced by a genetically modified strain of Aspergillus oryzae and is presented in two forms, coated (CT and liquid (L. The solid and liquid forms of the additive are considered equivalent in terms of safety and efficacy at the same dose. The final enzyme preparations contain no cultivable production organisms or recombinant DNA, given the limits of detection and evidence for the presence of deoxyribonuclease activity. The use of Ronozyme WX is safe at the maximum proposed dose for chickens and turkeys for fattening and piglets. This conclusion allows extrapolation to all minor poultry species for fattening and can be extended to pigs for fattening. Ronozyme WX is not genotoxic and no adverse effects were reported in a 90-day oral toxicity study. Therefore, the use of Ronozyme WX as a feed additive is not considered to pose a risk to consumers of animal products derived from animals treated with the additive. No studies of the additive that are relevant to user safety were carried out. However, the enzyme concentrate in Ronozyme WX was tested and was found not to be irritant to skin or eyes. In the absence of data, and given the nature of the product, it should be treated as a potential skin/respiratory sensitiser. The active ingredient of Ronozyme WX is a protein and as such will be degraded/inactivated during passage through the digestive tract of animals. Therefore, no risks to the environment are expected. The efficacy of Ronozyme WX has been demonstrated in chickens, turkeys and ducks for fattening at a minimum proposed dose of 100 FXU/kg complete feed. This conclusion can be extended to all minor poultry species for fattening. Efficacy has also been demonstrated in piglets and in pigs for fattening at a minimum dose of 200 FXU/kg complete feed.

  14. Scientific Opinion on the safety and efficacy of Safizym® X (endo-1,4-beta-xylanase as a feed additive for chickens and turkeys for fattening and laying hens

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-01-01

    Full Text Available Safizym® X is an enzyme preparation of endo-1,4-beta-xylanase produced by a non-genetically modified strain of Trichoderma reesei which is presented in solid and liquid forms. The solid and liquid formulations are considered to be equivalent in terms of safety and efficacy for the target species. In the tolerance studies provided, the animals tolerated well 100-fold (chickens and laying hens or 10-fold (turkeys for fattening the minimum recommended dosage. Therefore, the FEEDAP Panel concludes that the additive is safe for chickens and turkeys for fattening at 1 400 IFP/kg feed and in laying hens at 840 IFP/kg feed. The results obtained in the toxicological studies are insufficient to reach conclusions on the safety for the consumers. The identity of the test item used and its relationship with the fermentation product that is used to formulate the additive was not provided. Therefore, the FEEDAP Panel cannot conclude on the safety of the additive for the consumer. The solid final formulation is not considered a skin or eye irritant; however, the liquid formulation should be considered as a skin and eye irritant. In the absence of data on skin sensitisation, and taking account of its proteinaceous nature, the additive is to be considered a potential skin and respiratory sensitiser. The active substance of Safizym® X is a protein, and as such will be degraded/inactivated during passage through the digestive tract of animals. Therefore, no risks to the environment are expected and no further environmental risk assessment is required. The FEEDAP Panel concludes that the additive has the potential to be efficacious at a dose of 1 400 IFP/kg feed in chickens and turkeys for fattening and at 840 IFP/kg feed in laying hens.

  15. Production and characterization of an enzyme complex from a new strain of Clostridium thermocellum with emphasis on its xylanase activity Produção e caracterização de um complexo enzimático de uma nova linhagem de Clostridium thermocellum com enfase em sua atividade de xilanase

    Directory of Open Access Journals (Sweden)

    Werner Bessa Vieira

    2007-06-01

    Full Text Available A new bacterial strain (ISO II was isolated from manure cow and identified as phylogenetically close to the thermophilic cellulolytic bacterium Clostridium thermocellum. The new strain produced extracellular xylanase, pectinase, mannanase and cellulase activities when grown in liquid culture medium containing banana stem as carbon source. The enzyme production profile after growth on banana stem showed that xylanase and cellulase activities were detected in different incubation periods. An enzyme complex containing xylanase, cellulase and mannanase activities was isolated from culture supernatant samples of strainISO II. The complex was partially purified by ultrafiltration and gel filtration chromatography on Sephacryl S-300. Zymogram analysis after SDS-PAGE presented at least 05 subunits with xylanase activity. The enzyme showed single protein and xylanase activity bands after electrophoresis under non-denaturing conditions. The hydrolysis of xylan was optimal at temperature range of 55-75ºC and pH 6.0. Xylanase activity was quite stable at 65ºC, retaining 80% of its original activity after 12 h incubation. The apparent Km values, using insoluble and soluble arabinoxylans as substrates, were 1.54 and 11.53 mg/mL, respectively. Xylanase was activated by dithiothreitol, L-tryptophan and L-cysteine and strongly inhibited by N-bromosuccinimide and CoCl2. The characterization of mannanase showed Km and temperature optimum of 0.846 mg/mL and 65ºC, respectively and pH 8.0. By contrast to xylanase, it was less stable at 65ºC with half-life of 2.5 h and inhibited by dithiothreitol and Ca2+.Uma nova linhagem de bactéria (ISO II foi isolada de esterco bovino e identificada como filogeneticamente próxima à bactéria termofílica Clostridium thermocellum. A nova linhagem produziu atividades de xilanase, mananase, pectinase e celulase quando cultivada em meio de cultura líquido contendo engaço de bananeira como fonte de carbono. O perfil de produ

  16. 一株产木聚糖酶放线菌的液体发酵条件优化及水解特性研究%Optimization of Liquid Fermentation Conditions for Xylanase Production by a Actinomyces and Characterization of the Enzyme

    Institute of Scientific and Technical Information of China (English)

    朱运平; 禇文丹; 李秀婷; 滕超; 李娥; 杨然

    2012-01-01

    以木聚糖为唯一碳源制作选择培养基,利用透明圈法筛选高产木聚糖酶菌株,对其中一株产酶较高的菌株L10608进行液体发酵条件优化并对所产木聚糖酶的水解特性进行研究。结果表明:菌株L10608最佳产酶条件为以质量浓度25g/L、80目的水不溶性玉米芯木聚糖为碳源,10g/L大豆蛋白胨和5g/L酵母浸膏为复合氮源,初始pH6.0、培养温度40℃、转速200r/min、表面活性剂吐温-80质量浓度4g/L,最佳产酶条件下木聚糖酶活力达1074.8U/mL。以桦木木聚糖、榉木木聚糖和燕麦木聚糖为底物研究菌株L10608所产木聚糖酶的水解特性,结果表明该木聚糖酶为内切型木聚糖酶,水解主要产物为木二糖和木三糖。表明菌株L10608有望作为功能性低聚木糖的生产菌株。%In the current study, high-xylanase-producing strain was screened from different soil samples by transparent circle method, using xylan as the only carbon source in medium. The cultural condition for xylanase production by strain L10608 was optimized and the hydrolysis property of the enzyme was further investigated. The results indicated that the optimum fermentation medium contained a carbon source of water-insoluble xylan (80 mesh) of 25 g/L, compound nitrogen source of soya peptone of 25 g/L and yeast extract of 5 g/L, initial pH 6.0, cultural temperature 40 ℃, rotational speed of 200 r/min, surfactant polysorbate 80 of 4 g/L. Under the optimized condition, the enzyme activity reached 1074.8 U/mL. The xylanase utilized all birch wood xylan, beech wood xylan and oat xylan as the substrate, exhibiting that xylanase produced by L10608 was endo-xylanase with xylobiose and xylotriose as the major hydrates. These results showed that strain L10608 could hopefully be used for industrial production of functional xyloolygosaccharides.

  17. 厌氧菌群SVY42产酶条件分析及产木聚糖酶菌株的分离鉴定%Enzyme-Producing Conditions Analysis of Anaerobic Bactearial Population SVY42 andIsolation and Identification of a Xylanase-Producing Strain

    Institute of Scientific and Technical Information of China (English)

    赵超; 李婷; 邓云金; 刘晓艳; 黄一帆; 刘斌

    2013-01-01

    A highly effective and stable cellulose and hemicellulose degradable anaerobic bacterial population (ABP) SVY42 from the samples collected from Great Basin Hot Spring in Nevada,USA as material was enriched with and obtained.Their production conditions of CMCase,β-galactosidase and xylanase by ABP SVY42 were studied with the giant Juncao,bagasse,waste mushroom culturing cylinder,sodium carboxymethyl cellulose (CMC),filter paper and xylan as carbon sources.Based on these,a xylanase high-producing strain was screened using xylan as substrate.The highest β-galactosidase activity was 0.23 U/mL using the giant Juncao as substrate.The highest CMCase and xylanase activities were 0.31 U/mL and 0.35 U/mL using xylan as substrate respectively.A xylanase high-producing thermophilic strain SVY42-1 from ABP SVY42 was screened from ABP SVY42.The xylanase activity reached 0.26 U/mL under the optimal temperature (41℃) and pH (8.0).Strain SVY42-1 was identified by 16S rDNA sequencing analysis and only 93.8% similar to the highest homology of the known strains,and identified initially belong to a new genus.%以美国内华达州大盆地温泉采集样品为材料,富集获得纤维素及半纤维素高效稳定降解厌氧菌群SVY42,以巨菌草、甘蔗渣、废菇筒、羧甲基纤维素钠、滤纸、木聚糖为碳源,分析菌群SVY42产内切葡聚糖酶(CMC酶)、β-葡萄糖苷酶和木聚糖酶的情况.在此基础上,以木聚糖为底物筛选高产木聚糖酶的菌株.菌群SVY42在以巨菌草作为碳源时的β-葡萄糖苷酶活最高为0.23 U/mL,以木聚糖作为碳源时CMC酶活和木聚糖酶活均为最高,分别为0.31 U/mL和0.35 U/mL.从菌群SVY42中筛选得到1株高产木聚糖酶厌氧菌株SVY42-1,该菌在最适温度41℃和pH 8.0条件下,其木聚糖酶活力为0.26 U/mL,对其进行16S rDNA序列系统进化分析,SVY42-1与已知菌株的最高同源性仅为93.81%,初步鉴定属于新属.

  18. Efficiency of new fungal cellulase systems in boosting enzymatic degradation of barley straw lignocellulose

    DEFF Research Database (Denmark)

    Rosgaard, L.; Pedersen, S.; Meyer, Anne Boye Strunge

    2006-01-01

    This study examined the cellulytic effects on steam-pretreated barley straw of cellulose-degrading enzyme systems from the five thermophilic fungi Chaetomium thermophilum, Thielavia terrestris, Thermoascus aurantiacus, Corynascus thermophilus, and Myceliophthora thermophila and from the mesophile...... Penicillum funiculosum. The catalytic glucose release was compared after treatments with each of the crude enzyme systems when added to a benchmark blend of a commercial cellulase product, Celluclast, derived from Trichoderma reesei and a P-glucosidase, Novozym 188, from Aspergillus niger. The enzymatic...... treatments were evaluated in an experimental design template comprising a span of pH (3.5-6.5) and temperature (35-65 degrees C) reaction combinations. The addition to Celluclast + Novozym 188 of low dosages of the crude enzyme systems, corresponding to 10 wt % of the total enzyme protein load, increased...

  19. 嗜热脂肪土芽孢杆菌木聚糖酶基因的合成及其在大肠杆菌中的表达%De novo Synthesis and Expression of a Thermostable Xylanase from Geobacillus stearothermophilus in Escherichia coil

    Institute of Scientific and Technical Information of China (English)

    张志刚; 裴小琼; 吴中柳

    2009-01-01

    The endoxylanase XT6 secreted from Geobacillus stearothermophilus is a particularly attractive candidate for some industrial purposes and was used successfully on an industrial-scale mill trial. The gene was de novo synthesized with the codons adjusted to fit the bias of that of Escherichia coli and constructed into vector pET28a (+). After optimizing the expression conditions, functional xylanase XT6 was over expressed in E. coll with up to 65% of total protein. A maximum xylanase activity of 3,030 U/mL was obtained from cell extract against birchwood xylan. The recombinant XT6 was partly characterized and was similar with those of the native enzyme in G. stearothermophilus. This is the first report on the over expression of a de novo synthesized xylanase XT6 gene from Geobacillus stearothermophilus. Fig 6, Tab 1, Ref 19%来自嗜热脂肪土芽孢杆菌的木聚糖内切酶XT6在工业上有着重要的应用,已经成功应用于工业规模的生产试验.本文作者在合成XT6基因全序列的同时对其密码子进行了优化,且构建重组质粒在大肠杆菌中高表达.通过优化表达条件,功能正常的XT6基因在大肠杆菌中成功过量表达,蛋白表达量占细胞中总蛋白的65%.重组表达的木聚糖内切酶XT6特性和天然酶相似,以桦木木聚糖为底物测定细胞提取物中木聚糖酶活性,最大活性高达3 030 U/mL.本文首次报道了来自嗜热脂肪土芽孢杆菌中木聚糖酶基因全序列的合成和在大肠杆菌中成功过量表达.图6表1参19

  20. Effect of Inducers on Xylanase Activity and Biosynthesis of Ferulic Oligosaccharides in Aureobasidium pullulans%诱导物对出芽短梗霉木聚糖酶活力和阿魏酰低聚糖合成的调控影响

    Institute of Scientific and Technical Information of China (English)

    张雨青; 余晓红; 顾振新; 屠康

    2012-01-01

    Feruloyl oligosaccharides(FOs) could be produced as a result of the hydrolysis of wheat bran fiber by xylanase synthesized during fermentation by a mutant strain of Aureobasidium pullulans without the secretion of melanin bred using wheat bran.The effects of inducers such as carbon source,nitrogen source,metal ion and surfactant on the activity of xylanase and the formation of FOs were investigated.The medium composition for FOs production by the strain was optimized using the orthogonal array design method.The highest Fos production and xylanase activity,627 nmol/L and 52.66 IU/mL,respectively,were achieved by using a medium comprised of 50 g/L wheat bran,15 g/L glucose,1 g/L peptone and 1 g/L corn syrup.%以麦麸为原料诱变选育的不产黑色素出芽短梗霉为发酵菌株,利用其发酵过程中合成的木聚糖酶水解麦麸纤维,制备阿魏酰低聚糖(FOs)。研究碳源、氮源、金属离子和表面活性剂等诱导物对出芽短梗霉木聚糖酶活力和FOs合成的影响,以探明各物质对出芽短梗霉木聚糖酶活力和FOs合成的影响;利用正交试验设计方法研究各物质添加量对出芽短梗霉产酶和FOs的影响,确定芽短梗霉发酵制备FOs的最佳培养基。结果表明:50g/L麦麸处理液中添加15g/L葡萄糖、1g/L蛋白胨和1g/L玉米浆,FOs产量和木聚糖酶活力最高分别达到627nmol/L和52.66IU/mL。

  1. Produção de xilanases por uma cepa selvagem de Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2095 Xylanase production by a wild strain of Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2095

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Ferreira Costa

    2003-04-01

    Full Text Available Uma cepa selvagem de Aspergillus nidulans isolada de solo produziu xilanase isenta de atividade celulolítica quando desenvolvida em meio submerso contendo sabugo de milho como principal substrato. Produção máxima de xilanase (220 U/mL foi obtida quando a cepa foi desenvolvida em meio mineral suplementado com sabugo de milho a 3% (p/v por 6 dias. Eletroforese com SDS revelou a ocorrência de quatro iso-xilanases, com pesos moleculares de 50, 43, 20 e 18 kDa. A xilanase bruta foi resistente à precipitação com acetona, apresentando atividade ótima em pH 5.0-6.0 e temperatura entre 50º e 55ºC. A enzima exibiu grande estabilidade quando exposta a condições alcalinas, e foi estável por várias horas quando exposta a temperaturas de até 55ºC, retendo 50% e 23% de sua atividade quando aquecida por 1 h a 60 e 65ºC, respectivamenteA wild strain of Aspergillus nidulans isolated from soil produce cellulase-free xylanase activity when developed on submerged cultures using corn cob powder as the main substrate. Maximum xylanase production (220 U/mL was obtained when the strain was developed in mineral medium supplemented with 3% (w/v corn cob for 6 days. SDS-PAGE revealed the occurrence of four isoxylanases with molecular weights of 50, 43, 20 and 18 kDa. Crude xylanase was resistant to acetone precipitation with 80% of recovery. The enzyme had optimal activity at pH values between 5.0 and 6.0 and temperature between 50-55oC. The enzyme exhibited high stability under alkaline conditions and temperature up to 55oC. It retained 50% and 23% of its activity when heated for 1 h at 60 and 65oC, respectively

  2. 木聚糖酶诱导释放负电荷及其对漂白硫酸盐浆纤维胶体作用和留着的影响%Xylanase-induced liberation of negatively charged species and their effect on colloidal interactions and the retention of bleached kraft pulp ifbers

    Institute of Scientific and Technical Information of China (English)

    苗成; 刘忠

    2016-01-01

    The ability and specificity of various monocomponent endo-1,4-β-xylanases to release negatively charged species from never-dried, bleached, birch kraft pulp was studied. The effects of dissolution of these xylan-based components on pulp ifltrate properties and the subsmoluent chemical retention were determined. The results revealed that the amount of charged species released depended on the xylanase and that the ratio of charged species released to dissolved xylan is not linear. Chemical retention tests showed that high levels of dissolved xylan interfere with the ifxation of colloidal species, which was conifrmed by removing the dissolved hemicelluloses. The roles of residual hemicellulose and the properties of modified fibers on chemical retention and the level of internal sizing are discussed.%本文研究未干燥的漂白硫酸盐浆中各种内切-1,4-β-木聚糖酶组分释放负电荷的能力和特异性,同时分析木聚糖组分溶解液对浆料滤液性能和化学留着的影响。实验结果表明,电荷释放的数量和木聚糖酶相关,溶解木聚糖的质量和电荷释放量不成线性关系。化学留着实验表明,高含量溶解木聚糖能够影响胶体的固化作用,因为该过程能够移除溶解的半纤维素。本文探究残留的半纤维素和改性纤维性能对化学留着的作用和浆内施胶的影响。

  3. 不同木聚糖水平饲粮中添加木聚糖酶对断奶仔猪生长性能及肠道微生态环境的影响%Xylanase Supplementation of Diets Containing Different Levels of Xylan for Weaned Piglets: Effects on Growth Performance and Intestinal Microecology

    Institute of Scientific and Technical Information of China (English)

    叶楠; 陈代文; 毛湘冰; 黄志清; 毛倩; 陈洪; 韩国全; 余冰

    2011-01-01

    A 2 x 3 factorial design was conducted to study the effects of dietary xylan level and xylanase supplementation on growth performance, intestinal microbial metabolites and intestinal flora of weaned piglets. Tow main factors were xylanase supplementation (0 and 1 000 U/kg) and dietary xylan level (4. 58% , 6.23% and 7. 54% ). Thirty cross-bred (Duroc x Landrace x Large white) weaned piglets at 28 days of age with the similar weight and genetic background were randomly allotted to 6 treatments with 5 replicates each and 1 piglet in each replicate. The experiment lasted for 14 days. The results showed that during the experimental period from 1 to 14 days, the supplementation of xylanase increased the average daily gain (P 0. 05), and improved the total volatile fatty acid content of ileum digesta (P <0. 05), reduced the ammonia content of caecum digeta (P <0. 05), and increased the amount of Bifidobacterium in caecum digeta (P <0.05). When dietary xylan level was 7. 54% , the most significant effect of xylanase supplementation was found in those indexes ( P <0.05). However, dietary xylan level did not significantly affect those indexes. In conclusion, under the condition of this trial, the supplementation of xylanase can improve growth performance and intestinal microenvironment of weaned piglets. In addition, there is a dose-dependent relationship between xylanase supplementation and dietary xylan level.%本试验旨在研究不同木聚糖水平饲粮中添加木聚糖酶对断奶仔猪生长性能、肠道微生物代谢产物和菌群数量的影响.选择30头体重相近,遗传背景相似的28日龄“杜×长×大”三元杂交断奶阉公猪,采用2×3因子试验设计,设2个饲粮木聚糖酶添加量(0和1 000 U/kg)和3个饲粮木聚糖水平(4.58%、6.23%和7.54%),将仔猪随机分为6个处理,每个处理5个重复,每个重复1头猪,试验期14 d.结果表明:试验l~14 d,添加木聚糖酶能显著提高仔猪平均日增重(P<0.05)

  4. Dynamics and Modes of Action of Xylanases fromPenicillium corylophilum on Xylan%顶青霉木聚糖酶的水解动力学与水解模式

    Institute of Scientific and Technical Information of China (English)

    杨瑞金; 许时婴; 王璋

    2001-01-01

    从顶青霉(Penicillium corylophilum)培养液中分离纯化得到的3种木聚糖酶组分(Part A, Part B 和 Part C),对其水解动力学和水解模式的研究结果表明,3种木聚糖酶的动力学常数(桦木木聚糖为底物)分别为:Part A,Km=1.00 mg/mL,Vmax=0.159 U/mL;Part B, Km=1.59 mg/mL, Vmax=0.274 U/mL;Part C,Km=0.85 mg/mL,Vmax=0.200 U/mL. 3种木聚糖酶的水解模式相同,主要从一端(非还原端)水解得到木三糖和木二糖,并且得到木三糖的速度大于得到木二糖的速度;水解会产生木四糖,但木四糖会很快进一步水解成木二糖,木四糖水解成木糖和木三糖的可能性极小;木三糖会进一步水解成木糖和木二糖,但速度不快;木二糖不会进一步水解。粗酶水解玉米芯木聚糖时,阿拉伯糖侧链的水解与木聚糖主链的水解同步进行,粗酶中含有水解阿拉伯糖基侧链的阿拉伯糖苷酶活力.%Dynamics and mode of acting on xylan of three parts of xylanases (Part A, Part B and Part C) separated and purified from a culture filtrate of Penicillium corylophilum No. P-3-31 were investigated. The Km and Vmax of the three purified enzymes with birchwood xylan as a substrate were 1.00 mg/mL and 0.159 U/mL for Part A ( pH 4.0, 50 ℃) , 1.59 mg/mL and 0.274 U/mL for Part B (pH 4.0,50 ℃) and 0.85 mg/mL and 0.200 U/mL for Part C (pH 5.5,50 ℃). Based on the dynamic studies, it was deduced that three purified enzymes had the same mode of action on xylan. Xylotriose and xylobiose were main hydrolysates of long-chain xylan by these enzymes. Xylooligosaccharides upwards from xylotetraose were immediately hydrolyzed, and xylotetraose was mainly hydrolyzed to xylobiose. Xylotriose was slowly hydrolyzed, but xylobiose was unable to be further hydrolyzed by these enzymes. The studies on the hydrolysis dynamics of xylan from corncob with crude enzyme showed that the hydrolysis of arabinose side-chain was almost

  5. 甲酸与纤维素酶和木聚糖酶对多花黑麦草与白三叶混合青贮料发酵品质的影响%Effects of formic acid, cellulase and xylanase on fermentation quality of Lolium multiflorum and Trifolium repens mixture silage during ensiling

    Institute of Scientific and Technical Information of China (English)

    庄苏; 丁立人; 周建国; 王恬

    2013-01-01

    To evaluate the effects of formic acid, cellulase and xylanase on fermentation quality of mixture silage during ensiling, 2 000 g chopped Lolium multijlorum(80% ) and Trifolium repens(20% ) mixtures were ensiled in laboratory plastic bag either untreated (control) or treated with formic acid, cellulase, formic acid plus cellulase, xylanase, formic acid plus xylanase, cellulase plus xylanase and formic acid plus cellulase plus xylanase, respectively. Triplicate bags were opened at 0 d,2d,4d,6d,8d and 30 d of ensiling for chemical analyses. The pH value in all treated silages was lower (P<0. 05) than control at the end of ensiling. The formic acid, enzyme or formic acid plus enzyme treatments enhanced (P<0. 05) water soluble carbohydrate content significantly compared with control at all ensiling periods. The lactic acid content and acetic acid content were higher (P<0. 05) in the enzyme treatment than those in the formic acid-contained treatments and control, respectively. However, the acetic acid content was lower ( P<0. 05 ) in formic acid-contained treatments than that in enzymes treated silages. Relative to control, all treatments had lower (P< 0. 05 ) ammonia-N concentrations during ensiling. The enzyme treatments effectively (P<0. 05) decreased neutral detergent fiber and acid detergent fiber contents in the silages. The results suggested that the addition of formic acid and enzymes improved the Lolium multiflorum and Trifolium repens mixture silage quality, and the enzyme treatments were better than formic acid treatments during ensiling.%为评价甲酸与纤维素酶和木聚糖酶处理后多花黑麦草与白三叶混合青贮料发酵品质的变化,试验将混合青贮料分为对照组(未处理)、甲酸添加组、纤维素酶添加组、甲酸+纤维素酶添加组、木聚糖酶添加组、甲酸+木聚糖酶添加组、纤维素酶+木聚糖酶添加组、甲酸+纤维素酶+木聚糖酶添加组共8组,每组3个重复.青贮原料按80

  6. BÚSQUEDA DE LAS MEJORES CONDICIONES PARA LA EXTRACCIÓN Y MEDIDA DE ACTIVIDAD DE CELULASA Y XILANASA EXTRAÍDAS DE LA CORTEZA DE PITAYA AMARILLA (Acanthocereus pitajaya Searching the Best Conditions for the Extraction and Activity Measurement of Cellulase and Xylanase Extracted from the Yellow Pitaya Fruit Peel (Acanthocereus pitajaya

    Directory of Open Access Journals (Sweden)

    YENNY MARITZA DUEÑAS GÓMEZ

    Full Text Available Para pitaya amarilla (Acanthocereus pitajaya se ha encontrado que el ablandamiento excesivo de la cáscara contribuye al deterioro del fruto, al aplicar diferentes técnicas de conservación en fresco. Dado que tanto la celulasa como la xilanasa se han vinculado con el ablandamiento de la cáscara de frutos, este trabajo se basó en la búsqueda de las mejores condiciones de extracción y medida de actividad de celulasa y xilanasa. El mejor sistema de extracción fue buffer fosfato 20 mM, NaCl 0,5 M, pH 7,0. Para la medida de actividad de celulasa es necesario incubar durante 60 min a 37 ºC, con un volumen de extracto enzimático crudo de 30 µL, empleando buffer acetato 100 mM a pH 5,0; los valores de constante aparente de Michaelis Menten (K M aparente y velocidad máxima (V MÁX fueron 0,279 mg/mL y 0,00014 nmol glucosa/min, respectivamente. Para determinar la actividad de xilanasa se establecieron 15 min de tiempo de incuba-ción, a 50 ºC, empleando 30 µL de extracto enzimático crudo a pH 4,0 (buffer acetato 100 mM; los valores de K M aparente y V MÁX para xilanasa fueron 0,073 mg/mL y 0,0011 nmol glucosa/min, respectivamente.By applying different conservation techniques on yellow pitaya fruit (Acanthocereus pitajaya it has been found that excessive softening of the peel contributes to the deterioration of the fruit. Due to that both cellulase and xylanase have been related to the softening of the fruit's peel; this work was based on the search of the best conditions not only for the extraction, but also for the activity measurement of both cellulase and xylanase. The best extraction system for both enzymes was 20 mM buffer phosphate, 0.5 M NaCl, pH 7.0. For the cellulase activity measurement it was necessary to incubate during 60 min at 37 ºC, with a volume of raw enzymatic extract of 30 µL, using buffer acetate 100 mM at pH 5,0; the values of apparent K M and V MÁX were 0.279 mg/mL and 0.00014 nmol glucose/min, respectively. To

  7. Expression of a Xylanase Gene Originated from Rumen Anaerobic FungiNeocallimastix frontalis inPichia pastoris%来源于瘤胃厌氧真菌Neocallimastix frontalis木聚糖酶在毕赤酵母中的表达

    Institute of Scientific and Technical Information of China (English)

    汪艳; 李晓; 陈勇; 武运

    2015-01-01

    厌氧真菌Neocallimastix frontalis是瘤胃中降解木聚糖和纤维素的主要微生物之一,其木聚糖酶具有潜在的应用价值.对来源于Neocallimastix frontalis木聚糖酶基因Xyn11B进行密码子优化;通过全基因合成优化后的木聚糖酶基因Xyn11Bm,构建该基因的酵母表达载体pPIC9K-Xyn11Bm,并在毕赤酵母GS115中诱导表达.摇瓶水平时,重组Xyn11Bm酶活性最高为4 874.8 U/mL.在10 L发酵罐中诱导96 h后,重组Xyn11Bm的酶活性为5 139.7 U/mL,菌体湿重和干重达到216.7 g/L和117.3 g/L.酶学性质分析表明,重组Xyn11Bm的最适反应温度为50℃,最适反应pH为5.0.在pH5.0-8.0时该酶具有较好的稳定性,但温度稳定性较差.底物特异性分析表明,重组Xyn11Bm可水解燕麦木聚糖、桦木木聚糖和可溶性木聚糖4-O-Me-D-glucurono-D-xylan,但不降解地衣多糖和大麦β-葡聚糖.结果表明重组Xyn11Bm具有潜在的应用价值.%The anaerobic fungus Neocallimastix frontalisis one of main microorganisms in the rumen degrading xylan and cellulose and its xylanase has the potential application value. In this study, a xylanase gene Xyn11B originated from N. frontaliswas codon optimized, and the optimized gene Xyn11Bm was synthesized. Based on the gene engineering technology, the yeast expression vector pPIC9K-Xyn11Bm was constructed, and the xylanase was induced and expressed in Pichia pastoris GS115. In shake flask level, enzyme activity of the recombinant Xyn11Bm reached the maximum up to 4874.8 U/mL. In 10 L fermentor, at 96 h after induction, the activity of recombinant enzyme was 5139.7 U/mL, cell wet weight and dry weight were 216.7 g/L and 117.3 g/L. Enzymatic properties analysis showed that the optimum reaction temperature and pH of Xyn11Bm were 50℃ and 5.0. In pH5.0-8.0, the enzyme had sound stability, but poor temperature stability. Substrate specificity analysis showed that recombinant Xyn11Bm could hydrolyze oat spelt xylan, birch xylan and soluble

  8. Adaptation of marine derived fungus Chaetomium globosum (NIOCC 36) to alkaline stress using antioxidant properties

    Digital Repository Service at National Institute of Oceanography (India)

    Ravindran, C.; Naveenan, T.

    was examined for its adaptation mechanism under alkaline stress using antioxidant properties. The aqueous extracts of C. globosum exhibited different levels of antioxidant activity in all the in vitro tests such as alpha, alpha...

  9. Influence of soil saprophyte fungus Chaetomium cochliodes on associative system "Triticum aestivum – Azospirillum brasilense"

    Directory of Open Access Journals (Sweden)

    E. P. Kopylov

    2009-11-01

    Full Text Available In laboratory and vegetative experiments the ability of soil ascomycete C. cochliodes 3250 to promote the penetration of Azospirillum nitrogen-fixing bacteria into roots’ inner tissues was shown. At the same time the endophytic association: spring wheat – Azospirillum nitrogen-fixing bacteria – soil saprophyte ascomycete C. cochliodes 3250 is forming. It allows activating the nitrogen fixation in the spring wheat roots zone and biosynthetic processes in plants, in particular: to raise glutamine synthetase activity, chlorophylls content in leaves and plants’ productivity.

  10. Chaetomium-like fungi causing opportunistic infections in humans: a possible role for extremotolerance

    NARCIS (Netherlands)

    Ahmed, Sarah A.; Khan, Ziauddin; Wang, Xue-wei; Moussa, Tarek A. A.; Al-Zahrani, Hassan S.; Almaghrabi, Omar A.; Sutton, Deanna A.; Ahmad, S.; Groenewald, Johannes Z.; Alastruey-Izquierdo, A.; Diepeningen, Anne; Menken, S. B. J.; Najafzadeh, M. J.; Crous, Pedro W.; Cornely, Oliver; Hamprecht, Axel; Vehreschild, Maria J. G. T.; Kindo, A. J.; de Hoog, G. Sybren

    2016-01-01

    Members of the family Chaetomiaceae are ubiquitous ascosporulating fungi commonly, which reside in soil enriched with manure or cellulosic materials. Their role as human pathogens is largely ignored. However, the ability of some species to grow at high temperature enables them to play an important r

  11. Chaetomium-like fungi causing opportunistic infections in humans: a possible role for extremotolerance

    NARCIS (Netherlands)

    S.A. Ahmed; Z. Khan; X. Wang; T.A.A. Moussa; H.S. Al-Zahrani; O.A. Almaghrabi; D.A. Sutton; S. Ahmad; J.Z. Groenewald; A. Alastruey-Izquierdo; A. van Diepeningen; S.B.J. Menken; M.J. Najafzadeh; P.W. Crous; O. Cornely; A. Hamprecht; M.J.G.T. Vehreschild; A.J. Kindo; G.S. de Hoog

    2015-01-01

    Members of the family Chaetomiaceae are ubiquitous ascosporulating fungi commonly, which reside in soil enriched with manure or cellulosic materials. Their role as human pathogens is largely ignored. However, the ability of some species to grow at high temperature enables them to play an important r

  12. Scientific Opinion on the safety and efficacy of Endofeed® DC (endo-1,3(4-beta-glucanase and endo-1,4-beta-xylanase as a feed additive for chickens for fattening, laying hens, pigs for fattening and minor poultry and porcine species

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-08-01

    Full Text Available The additive Endofeed® DC contains endo-1,3(4-beta-glucanase and endo-1,4-beta-xylanase from the fermentation product produced by a non-genetically modified strain of Aspergillus niger. The applicant seeks the re-evaluation of the product and the extension of its use to pigs for fattening, minor poultry and porcine species. Tolerance trials in chickens for fattening, laying hens and pigs showed that the animals tolerated well 100-fold the recommended dose. Therefore, the FEEDAP Panel concludes that the additive is safe for these target species. The conclusions reached on those species can be extrapolated to minor poultry species and to minor porcine species for fattening. In the absence of adequate studies, the FEEDAP Panel cannot conclude on the safety of Endofeed® DC for the consumer. No specific studies were provided regarding the safety for the user. Therefore, Endofeed® DC should be considered a potential skin and eye irritant, and a potential skin and respiratory sensitiser. The results obtained in efficacy studies performed in chickens for fattening, laying hens and pigs for fattening showed that the additive has the potential to improve the performance of the animals. The nominal dose at which the potential of the enzyme preparation is demonstrated is the recommended dose. The conclusions on the efficacy on the major poultry species and on pigs for fattening can be extrapolated to minor poultry species and minor porcine species for fattening, respectively.

  13. Scientific Opinion on the safety and efficacy of Rovabio® Spiky (endo-1,4-beta-xylanase and endo-1,3(4-beta-glucanase as a feed additive for chickens for fattening, chickens reared for laying and other minor poultry species (for fattening and reared for laying

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-07-01

    Full Text Available Rovabio® Spiky is an enzyme preparation, available in solid and liquid forms, of endo-1,4-beta-xylanase and endo-1,3(4-beta-glucanase. The enzymes present in the additive are produced by two strains of Penicillium funiculosum, one of them genetically modified. The additive is intended to be used as a feed additive for chickens for fattening, chickens reared for laying and other minor poultry species (for fattening and reared for laying. None of the production strains was detected in their respective products. The additive does not give rise to safety concerns with regard to the genetic modification. No recombinant DNA was detected in the product obtained from the genetically modified strain of P. funiculosum. Based on the results of a tolerance trial in chickens for fattening, the FEEDAP Panel concludes that the additive is safe for chickens for fattening under the recommended conditions of use. This conclusion can be extended to chickens reared for laying and can be extrapolated to minor poultry species for fattening or reared for laying. Based on the outcome of the toxicological studies performed with the products of fermentation used to formulate the additive, the additive is of no concern regarding consumer safety. The additive is not irritant to the skin or eyes. In the absence of data, it should be considered a potential skin sensitiser and potentially harmful if inhaled. No risks to the environment are expected from the use of the additive in animal nutrition. Based on the results obtained in three efficacy studies, the FEEDAP Panel concludes that the additive has the potential to be efficacious in chickens for fattening at the minimum recommended dose. This conclusion can be extended to chickens reared for laying and can be extrapolated to minor poultry species for fattening or reared for laying.

  14. The structure of the TFIIH p34 subunit reveals a von Willebrand factor A like fold.

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    Dominik R Schmitt

    Full Text Available RNA polymerase II dependent transcription and nucleotide excision repair are mediated by a multifaceted interplay of subunits within the general transcription factor II H (TFIIH. A better understanding of the molecular structure of TFIIH is the key to unravel the mechanism of action of this versatile protein complex within these vital cellular processes. The importance of this complex becomes further evident in the context of severe diseases like xeroderma pigmentosum, Cockayne's syndrome and trichothiodystrophy, that arise from single point mutations in TFIIH subunits. Here we describe the structure of the p34 subunit of the TFIIH complex from the eukaryotic thermophilic fungus Chaetomium thermophilum. The structure revealed that p34 contains a von Willebrand Factor A (vWA like domain, a fold which is generally known to be involved in protein-protein interactions. Within TFIIH p34 strongly interacts with p44, a positive regulator of the helicase XPD. Putative protein-protein interfaces are analyzed and possible binding sites for the p34-p44 interaction suggested.

  15. In TFIIH, XPD helicase is exclusively devoted to DNA repair.

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    Jochen Kuper

    2014-09-01

    Full Text Available The eukaryotic XPD helicase is an essential subunit of TFIIH involved in both transcription and nucleotide excision repair (NER. Mutations in human XPD are associated with several inherited diseases such as xeroderma pigmentosum, Cockayne syndrome, and trichothiodystrophy. We performed a comparative analysis of XPD from Homo sapiens and Chaetomium thermophilum (a closely related thermostable fungal orthologue to decipher the different molecular prerequisites necessary for either transcription or DNA repair. In vitro and in vivo assays demonstrate that mutations in the 4Fe4S cluster domain of XPD abrogate the NER function of TFIIH and do not affect its transcriptional activity. We show that the p44-dependent activation of XPD is promoted by the stimulation of its ATPase activity. Furthermore, we clearly demonstrate that XPD requires DNA binding, ATPase, and helicase activity to function in NER. In contrast, these enzymatic properties are dispensable for transcription initiation. XPD helicase is thus exclusively devoted to NER and merely acts as a structural scaffold to maintain TFIIH integrity during transcription.

  16. Using Group II Introns for Attenuating the In Vitro and In Vivo Expression of a Homing Endonuclease.

    Directory of Open Access Journals (Sweden)

    Tuhin Kumar Guha

    Full Text Available In Chaetomium thermophilum (DSM 1495 within the mitochondrial DNA (mtDNA small ribosomal subunit (rns gene a group IIA1 intron interrupts an open reading frame (ORF encoded within a group I intron (mS1247. This arrangement offers the opportunity to examine if the nested group II intron could be utilized as a regulatory element for the expression of the homing endonuclease (HEase. Constructs were generated where the codon-optimized ORF was interrupted with either the native group IIA1 intron or a group IIB type intron. This study showed that the expression of the HEase (in vivo in Escherichia coli can be regulated by manipulating the splicing efficiency of the HEase ORF-embedded group II introns. Exogenous magnesium chloride (MgCl2 stimulated the expression of a functional HEase but the addition of cobalt chloride (CoCl2 to growth media antagonized the expression of HEase activity. Ultimately the ability to attenuate HEase activity might be useful in precision genome engineering, minimizing off target activities, or where pathways have to be altered during a specific growth phase.

  17. Structure of the Tuberous Sclerosis Complex 2 (TSC2) N Terminus Provides Insight into Complex Assembly and Tuberous Sclerosis Pathogenesis.

    Science.gov (United States)

    Zech, Reinhard; Kiontke, Stephan; Mueller, Uwe; Oeckinghaus, Andrea; Kümmel, Daniel

    2016-09-16

    Tuberous sclerosis complex (TSC) is caused by mutations in the TSC1 and TSC2 tumor suppressor genes. The gene products hamartin and tuberin form the TSC complex that acts as GTPase-activating protein for Rheb and negatively regulates the mammalian target of rapamycin complex 1 (mTORC1). Tuberin contains a RapGAP homology domain responsible for inactivation of Rheb, but functions of other protein domains remain elusive. Here we show that the TSC2 N terminus interacts with the TSC1 C terminus to mediate complex formation. The structure of the TSC2 N-terminal domain from Chaetomium thermophilum and a homology model of the human tuberin N terminus are presented. We characterize the molecular requirements for TSC1-TSC2 interactions and analyze pathological point mutations in tuberin. Many mutations are structural and produce improperly folded protein, explaining their effect in pathology, but we identify one point mutant that abrogates complex formation without affecting protein structure. We provide the first structural information on TSC2/tuberin with novel insight into the molecular function.

  18. Samp1, a RanGTP binding transmembrane protein in the inner nuclear membrane.

    Science.gov (United States)

    Vijayaraghavan, Balaje; Jafferali, Mohammed Hakim; Figueroa, Ricardo A; Hallberg, Einar

    2016-07-01

    Samp1 is a transmembrane protein of the inner nuclear membrane (INM), which interacts with the nuclear lamina and the Linker of Nucleoskeleton and Cytoskeleton (LINC) complex in interphase and during mitosis, it localizes to the mitotic spindle. Samp1 was recently found to coprecipitate a protein complex containing Ran, a GTPase with fundamental regulatory functions both in interphase and in mitosis. To investigate the interaction between Samp1 and Ran in further detail, we have designed and expressed recombinant fusion proteins of the Chaetomium thermophilum homolog of Samp1 (Ct.Samp1) and human Ran. Pulldown experiments show that Samp1 binds directly to Ran and that Samp1 binds better to RanGTP compared to RanGDP. Samp1 also preferred RanGTP over RanGDP in living tsBN2 cells. We also show that the Ran binding domain is located between amino acids 75-135 in the nucleoplasmically exposed N-terminal tail of Samp1. This domain is unique for Samp1, without homology in any other proteins in fungi or metazoa. Samp1 is the first known transmembrane protein that binds to Ran and could provide a unique local binding site for RanGTP in the INM. Samp1 overexpression resulted in increased Ran concentrations in the nuclear periphery supporting this idea. PMID:27541860

  19. Bioabatement with xylanase supplementation to reduce enzymatic hydrolysis inhibitors

    Science.gov (United States)

    Bioabatement, using the fungus Coniochaeta ligniaria NRRL30616 can effectively eliminate enzyme inhibitors from pretreated biomass hydrolysis. However, our recent research suggested that bioabatement had no beneficial effect on removing xylo-oligomers which were identified as strong inhibitors to ce...

  20. 嗜极性木聚糖酶%Extremophilic Xylanase

    Institute of Scientific and Technical Information of China (English)

    郑春翠; 段文凯; 周晓云

    2007-01-01

    木聚糖酶内切水解木聚糖主链的1,4-β-D-糖苷键,木聚糖是植物细胞壁中一种主要的多糖.自然界中木聚糖是多种糖类的复合体,这就使得木聚糖酶呈现多态性和多域性,由此需将繁多的木聚糖酶进行归类.木聚糖酶的催化反应属于双置换机制.在已研究的真菌或细菌性木聚糖酶中,大多数在温和的条件下表现出最佳活性,但有很多在极端环境下生长的生物体,为了适应极端环境而产生嗜极性的酶,其中嗜酸的、嗜碱的、嗜热的木聚糖酶,现在已有广泛的研究.对嗜极性木聚糖酶的研究进展作了论述.

  1. Symbiodinium thermophilum sp. nov., a thermotolerant symbiotic alga prevalent in corals of the world's hottest sea, the Persian/Arabian Gulf

    OpenAIRE

    Hume, B. C. C.; .C. D'Angelo; Smith, E. G.; Stevens, J.R.; Burt, J.; Wiedenmann, J.

    2015-01-01

    Coral reefs are in rapid decline on a global scale due to human activities and a changing climate. Shallow water reefs depend on the obligatory symbiosis between the habitat forming coral host and its algal symbiont from the genus Symbiodinium (zooxanthellae). This association is highly sensitive to thermal perturbations and temperatures as little as 1°C above the average summer maxima can cause the breakdown of this symbiosis, termed coral bleaching. Predicting the capacity of corals to surv...

  2. Endophytic fungi associated with endogenous Boswellia sacra

    Directory of Open Access Journals (Sweden)

    SAIFELDIN A.F. EL-NAGERABI1,♥,

    2014-11-01

    Full Text Available Endophytic fungi associated with leaves and stem tissues of Boswellia sacra growing in Dhofar Mountains of Oman were investigated from May 2008 through October 2011. The biological diversity, tissue-preference and seasonal variations of fungi were evaluated. Forty-three species and 3 varieties of fungi were recovered as new records from this plant. Of these isolates, 35 species are new reports to the mycoflora of Oman, whereas 12 species were added to the list of fungal flora of the Arabian Peninsula. The genus Alternaria (12 species is the most prevalent genus recovered from 12.5-83.3% of the screened leaves and stem samples, followed by Aspergillus (5 species, 3 varieties, 6.9-86.1%, Mycelia sterilia (76.4%, Rhizopus stolonifer (62.5%, Drechslera (3 species, 40.3-54.2%, Cladosporium (3 species, 20.8-52.8%, Curvularia lunata (38.8%, Chaetomium (2 species, 15.3-26.3%, Penicillim spp. (9.8-27.8%, Fusarium (9 species, 6.9-27.8%, Ulocladium consortiale (27.8%, Mucor hiemalis (19.5%, and the remaining species (Scytalidium thermophilum, Phoma solani, Taeniolella exilis, and Botryodiplodia theobromae exhibited very low levels of incidence (4.2-11.1%. Endophytic colonization of the leaf tissues was greater (43 species, 3 varieties comparable to stem tissues (25 species. This indicates heterogeneity and tissue-preference, with no evidence of seasonal variation. Therefore, the isolation of many fungal species and sterile mycelia supports the biodiversity of the endophytic fungi invading B. sacra and the high possibility of isolating more fungal species using advanced molecular techniques.

  3. Deep transcriptome-sequencing and proteome analysis of the hydrothermal vent annelid Alvinella pompejana identifies the CvP-bias as a robust measure of eukaryotic thermostability

    Directory of Open Access Journals (Sweden)

    Holder Thomas

    2013-01-01

    Full Text Available Abstract Background Alvinella pompejana is an annelid worm that inhabits deep-sea hydrothermal vent sites in the Pacific Ocean. Living at a depth of approximately 2500 meters, these worms experience extreme environmental conditions, including high temperature and pressure as well as high levels of sulfide and heavy metals. A. pompejana is one of the most thermotolerant metazoans, making this animal a subject of great interest for studies of eukaryotic thermoadaptation. Results In order to complement existing EST resources we performed deep sequencing of the A. pompejana transcriptome. We identified several thousand novel protein-coding transcripts, nearly doubling the sequence data for this annelid. We then performed an extensive survey of previously established prokaryotic thermoadaptation measures to search for global signals of thermoadaptation in A. pompejana in comparison with mesophilic eukaryotes. In an orthologous set of 457 proteins, we found that the best indicator of thermoadaptation was the difference in frequency of charged versus polar residues (CvP-bias, which was highest in A. pompejana. CvP-bias robustly distinguished prokaryotic thermophiles from prokaryotic mesophiles, as well as the thermophilic fungus Chaetomium thermophilum from mesophilic eukaryotes. Experimental values for thermophilic proteins supported higher CvP-bias as a measure of thermal stability when compared to their mesophilic orthologs. Proteome-wide mean CvP-bias also correlated with the body temperatures of homeothermic birds and mammals. Conclusions Our work extends the transcriptome resources for A. pompejana and identifies the CvP-bias as a robust and widely applicable measure of eukaryotic thermoadaptation. Reviewer This article was reviewed by Sándor Pongor, L. Aravind and Anthony M. Poole.

  4. Application of thermoalkalophilic xylanase from Arthrobacter sp. MTCC 5214 in biobleaching of kraft pulp

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    released by enzyme treatment showed a characteristic peak at 280 nm indicating the presence of lignin in the released coloring matter. Enzymatic prebleaching of kraft pulp showed 20 % reduction in kappa number of the pulp without much change in viscosity...

  5. Assessment of xylanase activity in dry storage as a potential method of reducing feedstock cost.

    Science.gov (United States)

    Smith, William A; Thompson, David N; Thompson, Vicki S; Radtke, Corey W; Carter, Brady

    2009-05-01

    Enzymatic preprocessing of lignocellulosic biomass in dry storage systems has the potential to improve feedstock characteristics and lower ethanol production costs. To assess the potential for endoxylanase activity at low water contents, endoxylanase activity was tested using a refined wheat arabinoxylan substrate and three commercial endoxylanases over the water activity range 0.21-1.0, corresponding to water contents of 5% to >60% (dry basis). Homogeneously mixed dry samples were prepared at a fixed enzyme to substrate ratio and incubated in chambers at a variety of fixed water activities. Replicates were sacrificed periodically, and endoxylanase activity was quantified as an increase in reducing sugar relative to desiccant-stored controls. Endoxylanase activity was observed at water activities over 0.91 in all enzyme preparations in less than 4 days and at a water activity of 0.59 in less than 1 week in two preparations. Endoxylanase activity after storage was confirmed for selected desiccant-stored controls by incubation at 100% relative humidity. Water content to water activity relationships were determined for three lignocellulosic substrates, and results indicate that two endoxylanase preparations retained limited activity as low as 7% to 13% water content (dry basis), which is well within the range of water contents representative of dry biomass storage. Future work will examine the effects of endoxylanase activity toward substrates such as corn stover, wheat straw, and switchgrass in low water content environments.

  6. Evidence that pentosans and xylanase affect the re-agglomeration of the gluten network

    NARCIS (Netherlands)

    Wang, M.; Vliet, van T.; Hamer, R.J.

    2004-01-01

    In the gluten-starch separation process gluten is formed first as a result of breakdown of the gliadin-glutelin structures during mixing followed by their re-agglomeration. To date the effect of pentosans and enzymes have not been studied separately. A simple modification of TNO Glutomatic system en

  7. Shear-induced starch-gluten separation at very low water content aided by xylanases

    NARCIS (Netherlands)

    Hardt, N.A.; Chauhan, H.; Boom, R.M.; Goot, van der A.J.

    2014-01-01

    This study examines the influence of extremely low water content on shear-induced starch–gluten separation and how endoxylanases influence the separation by releasing water associated with arabinoxylan. Shearing was performed at a water content ranging from 34% to 43.5% (w/w). It was possible to con

  8. Improvement in the productivity of xylooligosaccharides from rice straw by feed xylanase with ultrafiltration

    OpenAIRE

    Wang Fei; Guohua Hu; Xiao Jianbo; Liu Yang

    2011-01-01

    The effective production of xylooligosaccharides (XOs) from rice straw was investigated. Rice straw contains rich hemicellulose which can be hydrolyzed by enzyme; the XOs were obtained under hydrothermal conditions. To improve the productivity of XOs, ultrafiltration was chosen to eliminate xylan in the XOs. Under optimum hydrolysis conditions (1000 IU enzyme/g, 35 0C, 10% substrate concentration, pH 6.5, 6 h), the DP was the lowest. After ultrafiltration, xylan was eliminated. On the b...

  9. Improvement in the productivity of xylooligosaccharides from rice straw by feed xylanase with ultrafiltration

    Directory of Open Access Journals (Sweden)

    Wang Fei

    2011-01-01

    Full Text Available The effective production of xylooligosaccharides (XOs from rice straw was investigated. Rice straw contains rich hemicellulose which can be hydrolyzed by enzyme; the XOs were obtained under hydrothermal conditions. To improve the productivity of XOs, ultrafiltration was chosen to eliminate xylan in the XOs. Under optimum hydrolysis conditions (1000 IU enzyme/g, 35 0C, 10% substrate concentration, pH 6.5, 6 h, the DP was the lowest. After ultrafiltration, xylan was eliminated. On the basis of experimental data, an industrial XO production process consisting of pretreatment, enzymatic treatment and purification was designed. Using the designed process, 2.9g dry of purified XO was produced from 50g dry rice straw power.

  10. Production of beta-xylanase and beta-xylosidase by the extremely halophilic archaeon Halorhabdus utahensis

    DEFF Research Database (Denmark)

    Wainø, M.; Ingvorsen, K.

    2003-01-01

    -xylosidase activity was optimal at 65degreesC. SDS-PAGE and zymogram techniques revealed the presence of two xylan-degrading proteins of approximately 45 and 67 kDa in culture supernatants. To our knowledge, this paper is the first report on hemicellulose-degrading enzymes produced by an extremely halophilic archaeon....

  11. Compositional Changes and Baking Performance of Rye Dough As Affected by Microbial Transglutaminase and Xylanase.

    Science.gov (United States)

    Grossmann, Isabel; Döring, Clemens; Jekle, Mario; Becker, Thomas; Koehler, Peter

    2016-07-20

    Doughs supplemented with endoxylanase (XYL) and varying amounts of microbial transglutaminase (TG) were analyzed by sequential protein extraction, quantitation of protein fractions and protein types, and determination of water-extractable arabinoxylans. With increasing TG activity, the concentration of prolamins and glutelins decreased and increased, respectively, and the prolamin-to-glutelin ratio strongly declined. The overall amount of extractable protein decreased with increasing TG level showing that cross-linking by TG provided high-molecular-weight protein aggregates. The decrease of the high-molecular-weight arabinoxylan fraction and the concurrent increase of the medium-molecular-weight fraction confirmed the degradation of arabinoxylans by XYL. However, XYL addition did not lead to significant improved cross-linking of rye proteins by TG. Volume and crumb hardness measurements of bread showed increased protein connectivity induced by XYL and TG. Significant positive effects on the final bread quality were especially obtained by XYL addition. PMID:27349134

  12. Studies on substrate specificity of β-xylanase from Streptomyces olivaceoviridis E-86

    OpenAIRE

    Yoshida, Shigeki

    1996-01-01

    Plant cell wall is the major reservoir of fixed carbon in nature,and consists of three major polymeric components,namely cellulose,hemicellulose,and lignin.β-1,4-Xylans are the most aboundant components of the hemicellulose and mainly found ...

  13. Dicty_cDB: Contig-U04414-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ... 44 8.6 1 ( DV547508 ) rbcmb0_000208 Chaetomium cupreum mycelium cDNA li... 44 8.6 1 ( DV547506 ) rbcmb0_...000206 Chaetomium cupreum mycelium cDNA li... 44 8.6 1 ( DV547503 ) rbcmb0_000203... Chaetomium cupreum mycelium cDNA li... 44 8.6 1 ( DV547502 ) rbcmb0_000202 Chaetomium cupreum mycelium cDNA... li... 44 8.6 1 ( DV547441 ) rbcmb0_000101 Chaetomium cupreum mycelium cDNA li... 44 8.6 1 ( DB915235 ) Idio

  14. Thermal stability of xylanases produced by Aspergillus awamori Estabilidade térmica de xilanases produzidas por Aspergillus awamori

    Directory of Open Access Journals (Sweden)

    Judith Liliana Solórzano Lemos

    2000-09-01

    Full Text Available The effect of temperature on the activity and stability of endoxylanase and beta-xylosidase from Aspergillus awamori was investigated. The growth of A. awamori in milled sugar cane bagasse produced predominantly extracellular endoxylanase (30 U/ml and lower amounts of beta-xylosidase (1.3 U/ml. Grown in sugar cane bagasse as the principal carbon source, the microorganism produced a quite stable beta-xylosidase in a temperature range of 35-55°C, but it exhibited a lower thermostable endoxylanase. The thermostability of endoxylanase was enhanced through addition of polyhydric alcohols, mainly 2 M xylitol and sorbitol solutions. Particular stability upon storage (100% was found for endoxylanase at -4°C for 165 days. Yet for beta-xylosidase, an activity decrease of approximately 20% was observed during the first 15 days of storage, maintaining roughly 75% of initial activity until the end of the experiment.O presente trabalho trata do estudo do efeito da temperatura na atividade e estabilidade de endo-xilanase e beta-xilosidase produzidas, extracelularmente, por Aspergillus awamori. O cultivo deste microrganismo, em bagaço de cana finamente dividido, produziu predominantemente endo-xilanases (30 U/ml e menores atividades de beta-xilosidase (1,3 U/ml; esta última exibiu considerável estabilidade em faixa de temperatura variando de 35 a 55°C, por outro lado verificou-se uma menor termo estabilidade para a endoenzima. A estabilidade térmica de endo-xilanase foi aumentada consideravelmente através da adição de polióis, principalmente xilitol e sorbitol em concentração de 2,0 M. No que concerne à estocagem a baixa temperatura (-4°C, observou-se uma estabilidade particular na atividade endo-xilanásica (100%, durante 165 dias, porém, um decréscimo de aproximadamente 20% na atividade beta-xilosidásica foi verificado após os primeiros 15 dias de armazenamento nas mesmas condições, mantendo-se aproximadamente em 75% da atividade inicial no mesmo período de tempo.

  15. Partial Optimization of Endo-1, 4-Β-Xylanase Production by Aureobasidium pullulansUsing Agro-Industrial Residues

    Directory of Open Access Journals (Sweden)

    Shaghayegh Nasr

    2013-12-01

    This finding indicates the feasibility of growing of A. pullulans strain SN090 on wheat bran as an alternate economical substrate in order for reducing the costs of enzyme production and using this fortified agro-industrial byproduct in formulation of animal feed.

  16. Cellulose and hemicellulose-degrading enzymes in Fusarium commune transcriptome and functional characterization of three identified xylanases

    DEFF Research Database (Denmark)

    Yuhong, Huang; Busk, Peter Kamp; Lange, Lene

    2015-01-01

    and hemicellulose-degrading enzymes of classical fungal enzyme producers with those of Fusarium species. The results indicated that Fusarium species are robust cellulose and hemicellulose degraders. Wheat bran, carboxymethylcellulose and xylan-based growth media induced a broad spectrum of lignocellulolytic enzymes...

  17. Dicty_cDB: Contig-U04139-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available N PROGRESS *** f... 38 8.8 2 ( DV547337 ) rbcma0_005360 Chaetomium cupreum mycelium cDNA li... 34 9.1 2 ( DV...547434 ) rbcma0_005590 Chaetomium cupreum mycelium cDNA li... 34 9.1 2 ( BI067048 ) pgf1n.pk010.h1 normalize

  18. Growth-promoting effect of thermophilic fungi on the mycelium of the edible mushroom Agaricus bisporus.

    OpenAIRE

    Wiegant, W.M.; Wery, J.; E. T. Buitenhuis; de Bont, J A

    1992-01-01

    The growth-promoting effect of the thermophilic fungus Scytalidium thermophilum in mushroom compost on the mycelium of the edible mushroom Agaricus bisporus was investigated. Results obtained by others were confirmed by showing that S. thermophilum leads to an increased hyphal extension rate of the mushroom mycelium. However, it was demonstrated that hyphal extension rates were not clearly related to mushroom biomass increase rates. A number of experiments pointed strongly towards CO2 as the ...

  19. BLEACHING OF SULFONATED CMP FROM BIO-TREATED WHEAT STRAW

    Institute of Scientific and Technical Information of China (English)

    HongYu; MenghuaQin; XuemeiLu; YinboQu; PeijiGao

    2004-01-01

    Wheat straw chemi-mechanical pulp was pretreated with a crude xylanase which was secreted by white rot fungus Phanerochaete Chrysosporium prior to hydrogen peroxide bleaching. The process of xylanase pretreatment and hydrogen peroxide bleaching was optimized. The xylanase treated pulp achieved a brightness gain of 5.8% ISO over the untreated pulp. The xylanase treatment was found to liberate reducing sugars and facilitating lignin removal. Fiber morphology of pulp treated with xylanase was also studied by SEM.

  20. Draft Genome Sequence of Pseudozyma brasiliensis sp. nov. Strain GHG001, a High Producer of Endo-1,4-Xylanase Isolated from an Insect Pest of Sugarcane.

    Science.gov (United States)

    Oliveira, Juliana Velasco de Castro; Dos Santos, Renato Augusto Corrêa; Borges, Thuanny A; Riaño-Pachón, Diego Mauricio; Goldman, Gustavo Henrique

    2013-01-01

    Here, we present the nuclear and mitochondrial genome sequences of Pseudozyma brasiliensis sp. nov. strain GHG001. P. brasiliensis sp. nov. is the closest relative of Pseudozyma vetiver. P. brasiliensis sp. nov. is capable of growing on xylose or xylan as a sole carbon source and has great biotechnological potential. PMID:24356824

  1. Construction of a Xylanase-Producing Strain of Brevibacterium lactofermentum by Stable Integration of an Engineered xysA Gene from Streptomyces halstedii JM8

    OpenAIRE

    Adham, Sirin A.I.; Campelo, Ana B.; Ramos, Angelina; Gil, José A.

    2001-01-01

    A xylanolytic strain of Brevibacterium lactofermentum containing the Streptomyces halstedii His-tagged xysA gene was generated. The new strain contains DNA derived from S. halstedii, expresses xylanolytic activity, and was obtained by an integrative process mediated by a conjugative plasmid targeted to a dispensable chromosomal region located downstream from the essential cell division gene ftsZ. The His-tagged Xys1 enzyme was constitutively expressed under the control of the kan promoter fro...

  2. Purification and Properties of Xylanase from Pseudomonas flu.%荧光假单胞菌产木聚糖酶的纯化和性质

    Institute of Scientific and Technical Information of China (English)

    苏玉萍; 王书翰; 欧凯

    2000-01-01

    用硫酸铵分级沉淀,葡聚糖凝胶分离技术,对荧光假单胞菌(Pseudomonas flu.)所产的半纤维素酶进行分离纯化,得到单一组分的木聚糖酶.通过凝胶电泳法,测得其摩尔式量为33000.研究表明,该酶的最适pH值为6.0,最适温度60℃.酶的动力学研究测出米氏常数Km值为4.76mg/mL.

  3. Effect of heat-treatment, phytase, xylanase and soaking time on inositol phosphate degradation in vitro in wheat, soybean meal and rapeseed cake

    DEFF Research Database (Denmark)

    Blaabjerg, Karoline; Carlsson, N G; Hansen-Møller, Jens;

    2010-01-01

    An in vitro method was used to evaluate the degradation of myo-inositol hexakisphosphate (InsP6) in non-heat-treated wheat (NHW), heat-treated wheat (HW), soybean meal (SBM) or rapeseed cake (RSC) soaked separately or in combination. The feedstuffs were soaked in water (20 °C) and samples were...

  4. Effect of xylanases on ileal viscosity, intestinal fiber modification, and apparent ileal fiber and nutrient digestibility of rye and wheat in growing pigs

    DEFF Research Database (Denmark)

    Lærke, Helle Nygaard; Arent, Susan; Dalsgaard, Søren;

    2015-01-01

    marker. Ileal effluent was collected for 8 h on d 5 and 7 and pooled for analysis. In Exp. 1, TR reduced intestinal viscosity of pigs fed rye from 9.3 mPa·s in the control diet (NX) to 6.0 mPa·s (P effect. None of the enzymes changed the concentration of total...... and coarse wheat (concentration of arabinoxylan in the liquid phase of digesta increased by 82.4% in fine wheat (P enzyme addition. Similar effects of enzyme were not seen with rye....... The concentration of xylooligosaccharides in the liquid phase of digesta increased with enzyme addition, but for xylose, it was only significant for wheat, for which it increased 3.9-fold (P enzyme combination increased...

  5. Purification of Clostridium thermocellum xylanase Z expressed in Escherichia coli and identification of the corresponding product in the culture medium of C. thermocellum.

    OpenAIRE

    Grépinet, O.; Chebrou, M C; Béguin, P

    1988-01-01

    An endoxylanase encoded by the xynZ gene of Clostridium thermocellum was purified from Escherichia coli harbouring a fragment of the gene cloned in pUC8. The purified enzyme showed two active bands of Mr 41,000 and 39,000, the latter one presumably derived from the former through proteolysis. The enzyme was highly active on xylan and para-nitrophenyl-beta-D-xylobioside. The major end product of xylan hydrolysis was xylobiose. With an antiserum raised against the enzyme purified from E. coli, ...

  6. 交联木聚糖酶聚集体的制备及其性质研究%Preparation and Characteristics of Cross-linked Xylanase Aggregates

    Institute of Scientific and Technical Information of China (English)

    任延刚; 朱启忠; 黄庆瑞; 王娜; 张瑞景

    2009-01-01

    制备了交联木聚糖酶聚集体(CLEAs),并对其酶学性质进行了研究,以提高木聚糖酶的稳定性.通过毛栓菌发酵分离得木聚糖酶,经硫酸铵沉淀后以戊二醛作为交联剂对其进行化学交联,制得CLEAs,并用常规方法测定了各种因素对游离木聚糖酶和CLEAs的影响.在对耐热性、有机相中稳定性和耐酸碱性的研究中,CLEAs均表现比游离酶有较高的稳定性,因此运用CLEA技术可提高木聚糖酶的稳定性,使其广泛应用于饲料等工业生产中.

  7. Effects of Exogenous NSP Enzymes(Xylanase, β-glucanase and Cellulase) on Morphology and Functions of Digestive Tract in Growing Pigs Fed with Paddy-Based Diets

    Institute of Scientific and Technical Information of China (English)

    XU Zi-rong; LU Jian-jun

    2003-01-01

    Ninety Landrace X Jia 35±0.40 kg weight growing pigs were randomly allotted to three treatments, each of which was replicated three times with ten pigs per replicate. The pigs were reared on either a conventional corn-based diet (control Ⅰ ) or a paddy-based diet (control Ⅱ ) or a paddy diet supplemented with 0.2% NSP enzymes (test group). All pigs were given ad libitum access to both feed and water. The results of feeding trial showed that supplementation of NSP enzymes significantly increased ADG by 8.78 % (P<0.05) and decreased F/G by 9.42% (P<0.05) over the control group Ⅱ. No significant differences were found in ADG and F/G between control group I and the test group. The digestive trial showed that adding NSP enzymes significantly improved apparent digestibility of CP, EE and CF by 18.76 (P<0.01), 16.04 (P <0.05) and 108.57%(P<0.05), respectively, compared to control Ⅱ. The activities of proteolytic enzyme and α-amylase in duodenal contents were increased by 99.07 (P<0.01) and 18.41% (P<0. 05) with the addition of NSP enzymes. No significant differences between test and control Ⅱ group were found in activities of the pepsin in the gastric content, the trypsin and lipase in duodenal contents, the disaccharidase and γ-glutany transferase (γ-GT) in intestinal mucosa, but there was a tendency towards higher activities associated with the NSP enzymes diet (P>0. 05). The lengths of the villi within the duodenal, jejunal and ileal sections of the small intestine of pigs receiving the NSP enzymes diet were increased by 23.68 (P<0. 05), 56.00 (P<0. 01)and 76.90%(P<0.01) respectively, relative to the pigs in control Ⅱ.

  8. Xylanase and Protease Increase Solubilization of Non-Starch Polysaccharides and Nutrient Release of Corn- and Wheat Distillers Dried Grains with Solubles

    DEFF Research Database (Denmark)

    Pedersen, Mads Brøgger; Dalsgaard, Søren; Arent, Susan;

    2015-01-01

    The use of distiller dried grains with solubles (DDGS) as alternative to conventional animal feed for non-ruminants is challenged by the high content of non-starch polysaccharides and varying protein quality. In this study the enzymatic degradation of corn- and wheat DDGS was evaluated, in vitro...

  9. Laboratory research on the efficacy of chlorine dioxide fumigation for the remediation of mold-contaminated buildings--conference paper

    Science.gov (United States)

    The purpose of this project was to determine the efficacy ofCl02 fumigation to inactivate viable mold, mycotoxins, and allergens on building materials. Alternaria alternata, Aspergillus versicolor, Aspergillus Jumigatus, Chaetomium globosum, and Stachybotrys chartarum were indivi...

  10. Purification, biochemical characterization and structural modelling of alkali-stable β-1,4-xylan xylanohydrolase from Aspergillus fumigatus R1 isolated from soil

    OpenAIRE

    Deshmukh, Rehan Ahmed; Jagtap, Sharmili; Mandal, Madan Kumar; Mandal, Suraj Kumar

    2016-01-01

    Background Aspergillus fumigatus R1 produced xylanase under submerged fermentation which degrades the complex hemicelluloses contained in agricultural substrates. Xylanases have gained considerable attention because of their tremendous applications in industries. The purpose of our study was to purify xylanase and study its biochemical properties. We have predicted the secondary structure of purified xylanase and evaluated its active site residues and substrate binding sites based on the glob...

  11. Separation and identification of endoxylanases from Bacillus subtilis and their actions on wheat bran insoluble dietary fibre

    OpenAIRE

    Xiaoping, Yuan; Jing, Wang; Huiyuan, Yao; Nihorimbere, Venant

    2005-01-01

    A novel and convenient method based on native polyacrylamide gel electrophoresis (PAGE) and homogenization extraction was used for the purification of xylanase from crude enzymes. Two xylanases were purified by this method from the crude enzyme preparation from the selected strain of Bacillus subtilis. Subsequent analysis with thin layer chromatography and high pressure liquid chromatography (HPLC) indicated that these two xylanases were endo-acting enzymes, designated xyl I and xyl II. Both ...

  12. Production, Purification, and Characterization of β-(1-4)-Endoxylanase of Streptomyces roseiscleroticus

    OpenAIRE

    Grabski, Anthony C.; Jeffries, Thomas W.

    1991-01-01

    Twelve species of Streptomyces that formerly belonged to the genus Chainia were screened for the production of xylanase and cellulase. One species, Streptomyces roseiscleroticus (Chainia rosea) NRRL B-11019, produced up to 16.2 IU of xylanase per ml in 48 h. A xylanase from S. roseiscleroticus was purified and characterized. The enzyme was a debranching β-(1-4)-endoxylanase showing high activity on xylan but essentially no activity against acid-swollen (Walseth) cellulose. It had a very low a...

  13. Purification and Properties of a Xylan-Binding Endoxylanase from Alkaliphilic Bacillus sp. Strain K-1

    OpenAIRE

    Ratanakhanokchai, Khanok; Kyu, Khin Lay; Tanticharoen, Morakot

    1999-01-01

    An alkaliphilic bacterium, Bacillus sp. strain K-1, produces extracellular xylanolytic enzymes such as xylanases, β-xylosidase, arabinofuranosidase, and acetyl esterase when grown in xylan medium. One of the extracellular xylanases that is stable in an alkaline state was purified to homogeneity by affinity adsorption-desorption on insoluble xylan. The enzyme bound to insoluble xylan but not to crystalline cellulose. The molecular mass of the purified xylan-binding xylanase was estimated to be...

  14. Cloning of Acidic Xylanase Gene and Its Secretion Expression in Pichia pastoris%酸性木聚糖酶基因的克隆及其在毕赤酵母中的分泌表达

    Institute of Scientific and Technical Information of China (English)

    李春华; 李翔; 马立新

    2005-01-01

    运用"鸟枪法"克隆构建了环境微生物的基因组文库,并从中筛选得到一个酸性木聚糖酶基因,命名为xyl3,其在GenBank中的登录号为gb:AY300805.BLAST分析表明,该基因的序列同源性很低,其中仅存在很短的木聚糖酶基因的同源片段,其编码的木聚糖酶属于Glycosyl hydrolases family 10,与来源于Geobacillus stearothermophilus的intra-cellularxylanase在氨基酸水平具77%同源性.该基因经T4 DNA polymerase处理后,克隆至经限制性内切酶Cpo Ⅰ和Not Ⅰ双酶切后的毕赤酵母表达载体pHBM905,获得重组质粒pHBM706.此重组质粒转化毕赤酵母GS115,经含有交联木聚糖的选择性培养平板和PCR扩增鉴定筛选得到重组毕赤酵母GS115(pHBM706).以0.5%甲醇于28℃诱导产酶,测得重组毕赤酵母GS115(pHBM706)在诱导的第36h产酶达最高值,所产粗酶液酶活为0.177 IU/mL.该酶的最适反应pH为5.5,最适反应温度为50℃.

  15. Enzymatic Hydrolysis of Wheat Arabinoxylan by a Recombinant "Minimal" Enzyme Cocktail Containing beta-Xylosidase and Novel endo-1,4-beta-Xylanase and alpha-L-Arabinofuranosidase Activities

    DEFF Research Database (Denmark)

    Sørensen, Hanne R.; Pedersen, Sven; Jørgensen, Christel T.;

    2007-01-01

    24 h at pH 5, 50 degrees C. A 10%:40%:50% mixture of Abf II, Abf III, and beta-xyl released 56 mg of arabinose and 91 mg of xylose per gram of vinasse dry matter after 24 h at pH 5, 50 degrees C. The optimal dosages of the "minimal" enzyme cocktails were determined to be 0.4, 0.3, and 0.2 g enzyme......This study describes the identification of the key enzyme activities required in a "minimal" enzyme cocktail able to catalyze hydrolysis of water-soluble and water-insoluble wheat arabinoxylan and whole vinasse, a fermentation effluent resulting from industrial ethanol manufacture from wheat...

  16. Selection of Trichoderma viride strains irritated by laser and optimization of the xylanase fermentation%激光诱变筛选木霉菌株及木聚糖酶发酵条件优化

    Institute of Scientific and Technical Information of China (English)

    刘真真; 茅文俊; 朱虹; 朱融融; 孙晓宇; 姚思德; 汪世龙

    2008-01-01

    本实验利用激光这一高效诱变手段,对野生菌株绿色木霉Tr-02进行辐照诱变,通过两轮的定向筛选,最终得到一株高产木聚糖酶的菌株.对突变株进行发酵条件优化,结果表明,以0.5%麸皮为碳源,0.5%蛋白胨为氮源,0.1%Tween-80作为产酶促进剂,培养基初始pH值为5.0,瓶装量100mL,接种两环,28℃,180 r/min培养48h,木聚糖酶活力达到281.21U·mL-1,较之相同条件出发菌株木聚糖酶活力增长31.83%.

  17. DIFFERENT APPROACHES OF USING MULTIPLE CULTURE ISOLATES- FUSARIUM OXYSPORUM F8, PENICILLIUM NOTATUM 101 AND ASPERGILLIUS NIGER F7 FOR HIGHER PRODUCTION OF CELLULASE AND XYLANASE FROM PINUS ROXBURHII NEEDLES

    OpenAIRE

    DIVYA TANDON; NIVEDITA SHARMA; RICHA KAUSHAL

    2013-01-01

    Diminishing fossil fuel reserve and increasing cost of fossil products have rekindled effort on conversion of lignocelluloses to renewable fuel. Among various lignocelluloses' biomass, Pinus roxburghii is a predominant forest species which is scattered throughout the world. The continous shedding of pine needles and its exceptionally slow biodegradation in nature leads to huge accumulation of needles on earth by posing a serious threat to our environment which affects th...

  18. 小麦型日粮中添加木聚糖酶对肉鸭生产性能的影响%Effect of xylanase supplementation in wheat based diet on the growth performance of meat ducks

    Institute of Scientific and Technical Information of China (English)

    杨加豹; 张滴; 魏敏

    2010-01-01

    本试验在小麦型基础日粮中分别添加木聚糖酶0、50、100、150、200g/t饲料(5000U/g酶)饲喂12日龄樱桃谷肉鸭,观察木聚糖酶对肉鸭生产性能的影响.结果表明:添加木聚糖酶对肉鸭生产性能影响不显著(P>0.05),单位增重饲料成本以添加量50 g/t(即每1 kg饲料含250U木聚糖酶)的有效含量为佳.

  19. Studies on the influencing factors for xylanase production by Pleurotus ostreatus SYJ-012%食用菌Pleurotus ostreatus SYJ042产木聚糖酶的影响因素研究

    Institute of Scientific and Technical Information of China (English)

    岳晓禹; 蔡青和; 牛天贵; 惠明; 隋继学; 张雪

    2006-01-01

    实验研究了食用菌SYJ042在液体培养条件下,不同的培养条件对该菌产木聚糖酶的影响.研究表明,培养条件(碳源、氮源、通气量、初始pH和接种量)对其产木聚糖酶有显著的影响.最佳碳源为2.5%玉米芯+2.5%麸皮,氮源为0.2%的蛋白胨,接种量每50mL发酵液加4块菌丝块,通气量为发酵液占容积的1/3,初始pH6.0.

  20. 平菇产木聚糖酶固态发酵条件优化和酶学性质研究%Study on enzymatic characteristics and solid-phase fermentation condition of xylanase from Pleurotus ostreatus

    Institute of Scientific and Technical Information of China (English)

    吴萍; 周鸣鸣; 盛伟

    2010-01-01

    利用平菇(Pleurotus ostreatus)降解甘蔗渣固态发酵生产木聚糖酶,通过单因素和正交实验确定最佳培养基组分及其配比,并时其粗酶的酶学性质进行了研究.结果表明:碳源为甘蔗渣8g:玉米芯2g,氮源为2.0%酵母膏,pH为4,料水比为1:3.2,装瓶量为5g/125mL三角瓶,培养10d时,得到的酶活力最高,产酶量可达2918.95 U/g.粗酶液的最适反应pH为5,最适反应温度为40℃,在pH4~6的范围内酶活性较稳定.温度的适应性较宽,在30~70℃的范围里,相对酶活仍保持在65%以上.

  1. The preparation and properties of the immobilized Xylanase by carrier-crosslinked enzyme aggregation%固载化木聚糖酶交联酶聚集体的制备及性质

    Institute of Scientific and Technical Information of China (English)

    王冬伟; 孙谧

    2016-01-01

    目的 提高木聚糖酶YS1069的稳定性、重复利用率以及便于从反应体系中分离.方法 本文将交联酶聚集体CLEAs技术与载体固定化技术相结合,用LKZ-128氨基型树脂对木聚糖酶CLEAs进行固定化,并对其性质进行初步研究.结果及结论 采用单因素法和响应面法对影响固定化酶活性的因素进行分析和优化,获得最佳固定化条件为:pH9.0的酶液,以2 mL的异丙醇为沉淀剂,沉淀1h,以1.59 g/L的京尼平为交联剂,交联2h,20℃的环境中固定化9.25h,加酶量为8 mg时回收率最高,达到65.63%,加酶量为60 mg时酶活性最高,达到190U/g.重复使用10次后,其相对酶活仍为42.3%,说明具有良好的批次操作稳定性.该酶经过固定化后热稳定性和pH稳定性均得到了提高.

  2. 金针菇产木聚糖酶固态发酵条件优化和酶学性质研究%Study on enzymatic characteristics and solid-phase fermentation condition of xylanase from flammulina velutipes

    Institute of Scientific and Technical Information of China (English)

    吴萍; 李正鹏

    2010-01-01

    以豆秸粉为主要原料,通过单因素和正交试验确定金针菇(Flammulina velutipes)固态发酵生产木聚糖酶最佳培养条件,并对其粗酶的酶学性质进行了研究.结果表明,碳源为豆秸粉∶玉米芯∶麸皮=7∶2∶1,氮源为1.5%的黄豆粉,pH为5,接种量为干料的20%,装瓶量为6 g/100 mL 三角瓶装,料水比为1∶2.1,培养天数5 d,在此培养条件下得到的酶活力最高,产量可达52 768.91 U/g.粗酶液的最适反应温度为60℃,最适反应pH为6.酶的pH稳定性及热稳定性较好,80℃时相对酶活力仍保持在40.41%.

  3. 米曲霉RIBl28耐酸性木聚糖酶的研究%Study on An Acid-Stable Xylanase from Aspergillus oryzae RIB128

    Institute of Scientific and Technical Information of China (English)

    陆健; 曹钰; 陈坚; 若林三郎

    2001-01-01

    通过RBB-Xylan筛选平板和固体培养方法获得了产木聚糖酶菌株米曲霉(Aspergillus oryzae) RIBl28.在液体发酵时木聚糖是有效的诱导底物.通过离子交换和凝胶过滤色谱纯化得到了一个耐酸性木聚糖酶(木聚糖酶B).它的相对分子质量为65 000,最适作用温度和pH分别为55 ℃(pH 6.5),它在50 ℃时很稳定,并且在pH 2.0时仍保留相当高的活性.木聚糖酶B含有较多的天冬氨酸、丝氨酸、苏氨酸和丙氨酸.

  4. Combinative Degradation of Xylan with Acetyl Xylan Esterase and Xylanase%乙酰木聚糖酯酶协同木聚糖酶降解木聚糖的研究

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    探讨了宇佐美曲霉(A spergillus usamii)乙酰木聚糖酯酶和第10、11家族木聚糖酶之间的协同作用.利用作者所在实验室构建保藏的3株工程酵母Pichia pastoris GS115/A uaxe、GS115/Auxyn11A和GS115/A uxyn10A进行甲醇诱导发酵,分别获得重组乙酰木聚糖酯酶和木聚糖酶.在木聚糖酶最适pH、40℃、料液质量体积比1 g:60 mL、水解2h的条件下分别研究了不同加酶量作用于小麦麸皮时生成的还原糖量.结果表明,乙酰木聚糖酯酶与第11家族木聚糖酶有更好的协同作用,并在添加量比(酶活力比)为5:1时所测协同效果最好,还原糖生成量较木聚糖酶单独作用增加了46%.因此,在乙酰木聚糖酯酶的作用下,木聚糖上乙酰基的去除,对提高木聚糖酶对木聚糖的水解效率具有重要作用.

  5. 木聚糖酶产生菌的分离筛选及酶学性质%Separation and Selection to Bacteria Strains Producting Xylanase and Their Enzymatic Properties

    Institute of Scientific and Technical Information of China (English)

    葛晓萍; 郭清吉; 石琰璟; 冯灵刚

    2007-01-01

    利用透明圈法从云南腾冲温泉出水口土样中粗筛出12株木聚糖酶产生茵,其中Xylan-12菌活力较高,对其进行了16S rDNA部分序列测定,经BLAST同源性分析确定其为Bacillus flavothermus.对Xylan-12产生的木聚糖酶进行了酶学性质的初步研究,结果表明,该酶的最适PH为6,最适温度为65℃.

  6. Coexpression and Application of Thermostable Xylanase and Glucuronidase%耐热木聚糖酶和葡萄糖醛酸苷酶的共表达及应用

    Institute of Scientific and Technical Information of China (English)

    沈艺红; 薛业敏; 侯静静; 许家兴; 李相前

    2015-01-01

    目的:提高海栖热袍菌(Thermotoga maritima MSB8)来源的木聚糖酶XynB和α-葡萄糖醛酸苷酶AguA生产效率并降低生产成本.方法:利用基因重组技术将海栖热袍菌的XynB和AguA基因置于不同表达盒下构建共表达载体pET-20b-xynB-aguA和pET-28a-xynB-aguA,分别转化大肠杆菌Escherichia coli JM109 (DE3)进行诱导表达,获得双酶混合物进而水解桦木木聚糖及玉米芯.结果:重组菌E.coli JM109 (DE3) /pET-28a-xynB-aguA比E.coli JM109 (DE3) /pET-20b-xynB-aguA产酶更具优势,在LB培养基中诱导培养8h,XynB和AguA的产量分别达到7.6 U/mL和0.5 U/mL,在TB培养基中培养,XynB可达到10.27 U/mL,AguA为1.5 U/mL.在80℃水解条件下,双酶比单一木聚糖酶能够更彻底降解桦木木聚糖,所得酶解液中木二糖的含量和纯度更高;从还原糖释放量及电子显微镜观察可以看出双酶液对农副产品玉米芯具有良好的降解作用.结论:XynB和AguA基因(T.maritima)的克隆共表达具有可行性,并且在生物转化、食品工业和饲料生产等领域具有潜在应用前景.

  7. 基于土壤宏基因组文库筛选非培养木聚糖酶基因%Screening of xylanase genes from the soil metagenomic library based on uncultured method

    Institute of Scientific and Technical Information of China (English)

    熊科; 高乐; 杨玉焕; 崔晓亭; 李秀婷

    2015-01-01

    采用物理化学法提取土壤基因组DNA,将土壤DNA纯化后采用序列筛选策略获得非微生物纯培养方式的木聚糖酶基因.序列筛选依据木聚糖酶保守序列设计简并引物,PCR扩增获得200 bp的木聚糖酶核心序列,构建了约5 000个克隆子的序列文库.随机挑取200个克隆子测序,获得11条来自未培养微生物的木聚糖酶核心序列.并对其中细菌源序列1~ 19进行研究,利用HiTAIL-PCR扩增细菌源序列1~19的木聚糖酶基因全长,分析其编码蛋白,并将其与表达载体pET-28a(+)连接后导入E.coli表达,超声破壁后测得木聚糖酶酶活力为(19.94±0.3) U/mL.利用序列筛选获取土壤宏基因组源木聚糖酶基因的研究为筛选获得土壤未培养微生物木聚糖酶基因新资源提供了新的途径.

  8. The occurrence and distribution of cellulolytic fungi and Fusarium in seven Montagu’s Harrier (Circus pygargus

    Directory of Open Access Journals (Sweden)

    Teresa Korniłłowicz-Kowalska

    2013-12-01

    Full Text Available A total of 45 species of cellulolytic fungi and ten Fusarium species were identified. Three genera (Chaetomium, Trichoderma, Fusarium represented 80% of the frequency of cellulolytic fungi. Of them, Chaetomium globosum, Trichoderma viride and T. koningii were some of the most frequent species. A high differentiation of the richness and frequency of species of cellulolytic fungi depending on the nest and its individual layers was observed. Reasons for the differences in the frequency and species composition of the fungi were discussed.

  9. Purification, crystallization and preliminary X-ray analysis of a thermostable glycoside hydrolase family 43 beta-xylosidase from Geobacillus thermoleovorans IT-08

    NARCIS (Netherlands)

    Rohman, Ali; van Oosterwijk, Niels; Kralj, Slavko; Dijkhuizen, Lubbert; Dijkstra, Bauke W.; Puspaningsih, Ni Nyoman Tri

    2007-01-01

    The main enzymes involved in xylan-backbone hydrolysis are endo-1,4-beta-xylanase and beta-xylosidase. beta-Xylosidase converts the xylo-oligosaccharides produced by endo-1,4-beta-xylanase into xylose monomers. The beta-xylosidase from the thermophilic Geobacillus thermoleovorans IT-08, a member of

  10. Use of family 8 enzymes with xylanolytic activity in baking

    OpenAIRE

    Dutron, Agnes; Georis, Jacques; Genot, Bernard; Dauvrin, Thierry; Collins, Tony; Hoyoux, Anne; Feller, Georges

    2012-01-01

    The present invention describes a method to improve the properties of a dough and/or a baked product by adding a bread or dough-improving agent containing a enzyme with xylanolytic activity belonging to glycoside hydrolases family 8. Preferred enzymes are the psychrophilic xylanase from Pseudoalteromonas haloplanktis and the mesophilic xylanase Y from Bacillus halodurans C-125.

  11. Potential use of cucumber (Cucumis sativus L.) endophytic fungi as seed treatment agents against root-knot nematode Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    Xiao-ning YAN; Richard A. SIKORA; Jing-wu ZHENG

    2011-01-01

    Seed treatment with endophytic fungi has been regarded as an effective method for plant parasitic nematode control. Endophytic fungi from cucumber seedlings were isolated and screened for their potential to be used as seed treatment agents against Meloidogyne incognita. Among the 294 isolates screened, 23 significantly reduced galls formed by M. incognita in greenhouse test. The 10 most effective isolates were Fusarium (5), Trichoderma (1), Chaetomium (1),Acremonium (1), Paecilomyces (1), and Phyllosticta (1). Their control efficacies were repeatedly tested and their colonizations as well as in vitro activity against M. incognita were studied. They reduced the number of galls by 24.0%58.4% in the first screening and 15.6%-44.3% in the repeated test, respectively. Phyllosticta Ph511 and Chaetomium Ch1001 had high colonizations on both the roots and the aboveground parts of cucumber seedlings. Fusarium isolates had colonization preference on the roots, their root colonizations ranging from 20.1% to 47.3% of the total root area. Trichoderma Tr882, Paecilomyces Pa972, and Acremonium Ac985 had low colonizations on both the roots and the aboveground parts. Acremonium Ac985, Chaetomium Ch1001, Paecilomyces Pa972, and Phyllosticta Ph511 produced compounds affecting motility of the second stage juveniles of M. incognita. Based on these results, Chaetomium Ch1001 was considered to have the highest potential as a seed treatment agent for M. incognita biocontrol.

  12. Synergy between cellulases and pectinases in the hydrolysis of hemp.

    Science.gov (United States)

    Zhang, Junhua; Pakarinen, Annukka; Viikari, Liisa

    2013-02-01

    The impact of pectinases in the hydrolysis of fresh, steam-exploded and ensiled hemp was investigated and the synergy between cellulases, pectinases and xylanase in the hydrolysis was evaluated. About half; 59.3% and 46.1% of pectin in the steam-exploded and ensiled hemp, respectively, could be removed by a low dosage of pectinases used. Pectinases were more efficient than xylanase in the hydrolysis of fresh and ensiled hemp whereas xylanase showed higher hydrolytic efficiency than the pectinase preparation used in the hydrolysis of steam-exploded hemp. Clear synergistic action between cellulases and xylanase could be observed in the hydrolysis of steam-exploded hemp. Supplementation of pectinase resulted in clear synergism with cellulases in the hydrolysis of all hemp substrates. Highest hydrolysis yield of steam-exploded hemp was obtained in the hydrolysis with cellulases and xylanase. In the hydrolysis of ensiled hemp, the synergistic action between cellulases and pectinases was more obvious for efficient hydrolysis.

  13. Generation of xylooligosaccharides from microwave irradiated agroresidues using recombinant thermo-alkali-stable endoxylanase of the polyextremophilic bacterium Bacillus halodurans expressed in Pichia pastoris.

    Science.gov (United States)

    Kumar, Vikash; Satyanarayana, T

    2015-03-01

    The recombinant Pichia pastoris harboring the endoxylanase gene (TSEV1xyl) of Bacillus halodurans TSEV1 yielded a high titer of extracellular xylanase (502±23 U ml(-1)) on induction with methanol. The purified recombinant xylanase (TSEV1xyl) displayed optimal activity at 80°C and pH 9.0. The glycosylated recombinant xylanase exhibited higher thermostability (T1/2 of 45 min at 80°C) than the native enzyme (T1/2 of 35 min at 80°C). The agroresidues subjected to pretreatment (soaking in alkali followed by microwave irradiation) liberated xylooligosaccharides (XOS) upon hydrolysis with the recombinant xylanase. The removal of unhydrolyzed agroresidues, xylanase and xylose from the hydrolysate by two-step ultrafiltration led to the purification of XOS as confirmed by TLC as well as HPLC analysis. PMID:25553569

  14. Antiviral property of marine actinomycetes against white spot syndrome virus in penaeid shrimps

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.S.; Philip, R.; Achuthankutty, C.T.

    components, and fucoidan, an algal polysacch a- ride 19,20 . In another study, oral administration of LPS at the rate of 20 ?g LPS per kg shrimp body weight ? 1 day ? 1 for 7 days against penaeid acute viraemia (PAV) resulted in 75% survival 20.... , Enhancement of disease resistance of kuruma shrimp, Penaeus japonicus, after oral administration of pept i do - glycan derived from Bifidobacterium thermophilum. Aquacu l ture , 1998, 164 , 277 ? 288. 20. Takahashi, Y. et al. , Enhancement of disease...

  15. Evaluation of the efficacy of three indigenous strains of entomopathogenic nematodes from Meghalaya, India against mustard sawfly, Athalia lugens proxima Klug (Hymenoptera: Tenthredinidae)

    OpenAIRE

    Yadav, Arun K; Lalramliana

    2012-01-01

    The objective of this study was to evaluate the efficacy of three indigenous strains of entomopathogenic nematodes (EPN) from Meghalaya, India, namely Heterorhabditis indica Poinar, Karunakar and David, Steinernema thermophilum Ganguly and Singh, and Steinernema glaseri (Steiner) against the last instar larva of mustard sawfly, Athalia lugens proxima Klug, a serious pest of mustard and radish in India. The larvae of A. lugens proxima were exposed to 10, 25, 50, 75 and 100 infective juveniles ...

  16. The effect of the introduction of exogenous strain Acidithiobacillus thiooxidans A01 on functional gene expression, structure and function of indigenous consortium during pyrite bioleaching.

    Science.gov (United States)

    Liu, Yi; Yin, Huaqun; Zeng, Weimin; Liang, Yili; Liu, Yao; Baba, Ngom; Qiu, Guanzhou; Shen, Li; Fu, Xian; Liu, Xueduan

    2011-09-01

    Acidithiobacillus thiooxidans A01 was added to a consortium of bioleaching bacteria including Acidithiobacilluscaldus, Leptospirillumferriphilum, Acidithiobacillus ferrooxidans, Sulfobacillus thermosulfidooxidans, Acidiphilium spp., and Ferroplasma thermophilum cultured in modified 9 K medium containing 0.5% (w/v) pyrite, and 10.7% increase of bioleaching rate was observed. Changes in community structure and gene expression were monitored with real-time PCR and functional gene arrays (FGAs). Real-time PCR showed that addition of At. thiooxidans caused increased numbers of all consortium members except At. caldus, and At. caldus, L. ferriphilum, and F. thermophilum remained dominant in this community. FGAs results showed that after addition of At. thiooxidans, most genes involved in iron, sulfur, carbon, and nitrogen metabolisms, metal resistance, electron transport, and extracellular polymeric substances of L. ferriphilum, F. thermophilum, and Acidiphilium spp., were up-regulated while most of these genes were down-regulated at 70-78 h in At. caldus and up-regulated in At. ferrooxidans, then down-regulated at 82-86 h.

  17. Expression of Critical Sulfur- and Iron-Oxidation Genes and the Community Dynamics During Bioleaching of Chalcopyrite Concentrate by Moderate Thermophiles.

    Science.gov (United States)

    Zhou, Dan; Peng, Tangjian; Zhou, Hongbo; Liu, Xueduan; Gu, Guohua; Chen, Miao; Qiu, Guanzhou; Zeng, Weimin

    2015-07-01

    Sulfate adenylyltransferase gene and 4Fe-4S ferredoxin gene are the key genes related to sulfur and iron oxidations during bioleaching system, respectively. In order to better understand the bioleaching and microorganism synergistic mechanism in chalcopyrite bioleaching by mixed culture of moderate thermophiles, expressions of the two energy metabolism genes and community dynamics of free and attached microorganisms were investigated. Specific primers were designed for real-time quantitative PCR to study the expression of these genes. Real-time PCR results showed that sulfate adenylyltransferase gene was more highly expressed in Sulfobacillus thermosulfidooxidans than that in Acidithiobacillus caldus, and expression of 4Fe-4S ferredoxin gene was higher in Ferroplasma thermophilum than that in S. thermosulfidooxidans and Leptospirillum ferriphilum. The results indicated that in the bioleaching system of chalcopyrite concentrate, sulfur and iron oxidations were mainly performed by S. thermosulfidooxidans and F. thermophilum, respectively. The community dynamics results revealed that S. thermosulfidooxidans took up the largest proportion during the whole period, followed by F. thermophilum, A. caldus, and L. ferriphilum. The CCA analysis showed that 4Fe-4S ferredoxin gene expression was mainly affected (positively correlated) by high pH and elevated concentration of ferrous ion, while no factor was observed to prominently influence the expression of sulfate adenylyltransferase gene. PMID:25941022

  18. Local adaptation constrains the distribution potential of heat-tolerant Symbiodinium from the Persian/Arabian Gulf.

    Science.gov (United States)

    D'Angelo, Cecilia; Hume, Benjamin C C; Burt, John; Smith, Edward G; Achterberg, Eric P; Wiedenmann, Jörg

    2015-12-01

    The symbiotic association of corals and unicellular algae of the genus Symbiodinium in the southern Persian/Arabian Gulf (PAG) display an exceptional heat tolerance, enduring summer peak temperatures of up to 36 °C. As yet, it is not clear whether this resilience is related to the presence of specific symbiont types that are exclusively found in this region. Therefore, we used molecular markers to identify the symbiotic algae of three Porites species along >1000 km of coastline in the PAG and the Gulf of Oman and found that a recently described species, Symbiodinium thermophilum, is integral to coral survival in the southern PAG, the world's hottest sea. Despite the geographic isolation of the PAG, we discovered that representatives of the S. thermophilum group can also be found in the adjacent Gulf of Oman providing a potential source of thermotolerant symbionts that might facilitate the adaptation of Indian Ocean populations to the higher water temperatures expected for the future. However, corals from the PAG associated with S. thermophilum show strong local adaptation not only to high temperatures but also to the exceptionally high salinity of their habitat. We show that their superior heat tolerance can be lost when these corals are exposed to reduced salinity levels common for oceanic environments elsewhere. Consequently, the salinity prevailing in most reefs outside the PAG might represent a distribution barrier for extreme temperature-tolerant coral/Symbiodinium associations from the PAG. PMID:25989370

  19. SYNONYMOUS CONDON USAGE BIAS AND OVEREXPRESSION OF A SYNTHETIC xynB GENE FROM Aspergillus niger NL-1 IN Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Fei Li, Shiyi Yang,

    2012-02-01

    Full Text Available To further improve the expression level of recombinant xylanase in Pichia pastoris, the xynB gene, encoding the mature peptide from Aspergillus niger NL-1, was designed and synthesized based on the synonymous condon bias of P. pastoris and optimized G+C content. 155 nucleotides were changed, and the GC content decreased from 57.7% to 43.6%. The synthetic xynB was inserted into the pPICZaA and then integrated into P. pastoris GS115. The activity of the recombinant xylanase reached 1414.7 U/mL, induced with 0.8% methanol after 14-day cultivation at a temperature of 28oC in shake flasks, which was 267% higher than that of the native gene. Furthermore, the maximum xylanase activity of 20424.2 U/mL was obtained by high-density fermentation in a 5-L fermenter, which was the highest xylanase expression in P. pastoris yet reported. The recombinant xylanase had its optimal activity at a pH of 5.0 and temperature of 50oC. The recombinant xylanase was stable over a pH range of 4.5 to 8.0. Thus, this report provides an industrial means to produce the recombinant xylanase in P. pastoris.

  20. Delignification outperforms alkaline extraction for xylan fingerprinting of oil palm empty fruit bunch.

    Science.gov (United States)

    Murciano Martínez, Patricia; Kabel, Mirjam A; Gruppen, Harry

    2016-11-20

    Enzyme hydrolysed (hemi-)celluloses from oil palm empty fruit bunches (EFBs) are a source for production of bio-fuels or chemicals. In this study, after either peracetic acid delignification or alkaline extraction, EFB hemicellulose structures were described, aided by xylanase hydrolysis. Delignification of EFB facilitated the hydrolysis of EFB-xylan by a pure endo-β-1,4-xylanase. Up to 91% (w/w) of the non-extracted xylan in the delignified EFB was hydrolysed compared to less than 4% (w/w) of that in untreated EFB. Alkaline extraction of EFB, without prior delignification, yielded only 50% of the xylan. The xylan obtained was hydrolysed only for 40% by the endo-xylanase used. Hence, delignification alone outperformed alkaline extraction as pretreatment for enzymatic fingerprinting of EFB xylans. From the analysis of the oligosaccharide-fingerprint of the delignified endo-xylanase hydrolysed EFB xylan, the structure was proposed as acetylated 4-O-methylglucuronoarabinoxylan.

  1. Examining the Potential of Plasma-Assisted Pretreated Wheat Straw for Enzyme Production by Trichoderma reesei

    DEFF Research Database (Denmark)

    Rodríguez Gómez, Divanery; Lehmann, Linda Olkjær; Schultz-Jensen, Nadja;

    2012-01-01

    Plasma-assisted pretreated wheat straw was investigated for cellulase and xylanase production by Trichoderma reesei fermentation. Fermentations were conducted with media containing washed and unwashed plasma-assisted pretreated wheat straw as carbon source which was sterilized by autoclavation...

  2. Construction and Identification of Plasmid pTA-TUB2

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    An about 1.40 Kb target gene fragment was yielded by PCR amplification with the plasmid pRB 129,which was identified by restriction enzyme digestion that the PCR product was TU B2 gene.The gene was digested by the restriction enzyme and was linked with pTA plasmid to construct pTA-TU B2 plasmid.The plasmid was transformed into Chaetomium spp.by PEG method and the transformation rate was 27/(2×105) and it is nine times higher than that of pRB 129.The transformants can grow on the PDA containing 1 000 μg*mL-1 carbendazim,which is 1 000 times higher than the original Chaetomium spp.The resistance was stable after 10 times transfer on non-selective medium.

  3. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, H.K.; Frisvad, Jens Christian;

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta-xylosidases. Th...... is a well known enzyme producer, this is the first report of xylanase and thermostable beta-xylosidase production from the newly identified, non-ochratoxin-producing species A. brasiliensis....

  4. Identification of thermostable β-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian;

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta-xylosidases. Th...... is a well known enzyme producer, this is the first report of xylanase and thermostable beta-xylosidase production from the newly identified, non-ochratoxin-producing species A. brasiliensis....

  5. The genes for three xylan-degrading activities from Bacteroides ovatus are clustered in a 3.8-kilobase region.

    OpenAIRE

    Whitehead, T. R.; Hespell, R B

    1990-01-01

    Genes coding for three xylan-degrading activities, xylanase, xylosidase, and arabinosidase, were simultaneously cloned from the colonic anaerobic organism Bacteriodes ovatus. The genes for the three enzymes were located on a 3.8-kilobase EcoRI genomic insert and were cloned by using plasmid pUC18. All three activities were expressed in Escherichia coli JM83, and all were cell associated. Expression of the xylanase gene was independent from expression of the xylosidase and arabinosidase genes,...

  6. Hemicellulases in the bleaching and characterisation of kraft pulps. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Suurnaekki, A.

    1996-03-01

    Xylanase-aided bleaching of kraft pulps is the major industrial application of hemicellulases in pulp processing. In addition to process aids, hemicellulases have recently also been shown to be promising tools in fibre analytics. In this work, the role of xylanase and mannanase pretreatments in the bleaching of softwood pulps produced by different sulphate cooking methods was studied. In addition, the action of hemicellulases in kraft fibres was characterized and exploited in the analysis of the suface composition of kraft pulps.

  7. Effect of Chlorine Dioxide Gas on Fungi and Mycotoxins Associated with Sick Building Syndrome

    OpenAIRE

    Wilson, S. C.; Wu, C; Andriychuk, L. A.; Martin, J. M.; Brasel, T. L.; Jumper, C. A.; Straus, D C

    2005-01-01

    The growth of indoor molds and their resulting products (e.g., spores and mycotoxins) can present health hazards for human beings. The efficacy of chlorine dioxide gas as a fumigation treatment for inactivating sick building syndrome-related fungi and their mycotoxins was evaluated. Filter papers (15 per organism) featuring growth of Stachybotrys chartarum, Chaetomium globosum, Penicillium chrysogenum, and Cladosporium cladosporioides were placed in gas chambers containing chlorine dioxide ga...

  8. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation

    OpenAIRE

    Tautorus, T. E.; Townsley, P. M.

    1983-01-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus no...

  9. Osmoregulatory and tegumental ultrastructural damages to protoscoleces of hydatid cysts Echinococcus granulosus induced by fungal endophytes

    OpenAIRE

    Verma, Vijay C; Gangwar, Mayank; Nath, Gopal

    2013-01-01

    Characteristic ultrastructural changes were observed when protoscoleces of hydatid cysts Echinococcus granulosus was treated with extract of endophytic fungi Eupenicillium and Chaetomium sp. isolated from Azadirachta indica and Piper longum plants respectively. A sharp decrease in viability of protoscoleces was observed after 6 h of incubation with fungal extracts. The ultrastructural changes included rosteller disorganization, loss of hooks and shedding of the microtriches of scolex region. ...

  10. Production of mycotoxins on artificially and naturally infested building materials

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Gravesen, S.; Nielsen, P.A.;

    1999-01-01

    In this study, the ability to produce mycotoxins during growth on artificially infested building materials was investigated for Penicillium chrysogenum, Pen. polonicum, Pen. brevicompactum, Chaetomium spp., Aspergillus ustus, Asp. niger, Ulocladium spp., Alternaria spp., and Paecilomyces spp., all......., alternariol and alternariol monomethyl ether were detected. From Ulocladium spp., Paecilomyces spp., and Asp. ustus no known mycotoxins were detected, although the latter two are known mycotoxin producers. Asp. niger produced several naphtho-gamma-pyrones and tetra-cyclic compounds. All investigated species...

  11. 一株嗜热菌产耐热木聚糖酶对馒头品质和保质期的影响%Effect of Thermo-tolerant Xylanase from Thermophilic Geobacillus sp.PZH1 on the Quality and Shelf-life of Steamed Bread

    Institute of Scientific and Technical Information of China (English)

    王石峰; 林孔亮; 秦晓培; 陈学敏; 刘培培; 郭小虎; 张波

    2011-01-01

    研究嗜热细菌Geobacillus sp.PZH1产耐热木聚糖酶对馒头品质及保质期的影响作用.从嗜热细菌Geobacillus sp.的PZH1制备木聚糖酶,添加到面粉中制作馒头,观察其对馒头品质和保质期的影响.结果表明:在馒头中添加适量的耐热木聚糖酶,能明显降低馒头的持水性,提高面筋网络的弹性,改变面团的加工及稳定性能,增大馒头体积,并能有效抑制馒头中细菌的生长,延长馒头的保质期.

  12. Content of Pentosan in Wheat Grain and Xylanase Supplementation on Measurements of AME and Nutrient Ingredient Digestibility of Cocks%小麦戊聚糖含量及添加木聚糖酶对鸡表观代谢能值和养分消化率的影响

    Institute of Scientific and Technical Information of China (English)

    王修启; 李春喜; 林东康; 常绢; 秦磊

    2002-01-01

    测定了河南省9个主栽小麦品种豫麦49号、豫麦47号、高优503、郑麦9023、豫麦34号、皖麦38、豫麦70号、孟12和河北8901的戊聚糖含量,结果表明,9个品种的戊聚糖含量为6.25%~8.23%;选取两个有代表性的品种豫麦70号和豫麦49号,用64只小公鸡进行代谢试验,评定添加1.2‰木聚糖酶对鸡表观代谢能(AME)值和养分消化率的影响.

  13. 黑曲霉固体发酵产木聚糖酶的响应面优化设计及其酶学性质的研究%Optimization of Solid State Fermentation Conditions for Xylanase Production by A spergillus niger Using Response Surface Methodology and the Enzymatic Properties

    Institute of Scientific and Technical Information of China (English)

    刘明启; 关荣发; 陈文伟

    2010-01-01

    本研究采用响应面法的中心组合对影响黑曲霉(aspergillus niger JL 15)固体发酵产木聚糖酶的条件进行了优化.以橘皮粉为基质,补充碳源、氮源,以及含水量和发酵时间对木聚糖酶产量具有显著影响(P<0.05).模拟二次多项式回归预测模型,并建立自变量与响应值的回归方程,获得各因素的最佳水平,即:甘油、硫酸铵的添加量分别为4.2%和3.1%,含水量为61%,发酵时间为73.4 h,木聚糖酶活性最大预测值达922.9 U/g干发酵产物,验证值为917.7 U/g干发酵产物,高出基础培养基酶活3.2倍.酶学性质分析研究表明,黑曲霉木聚糖酶(XylA)的最适温度和最适pH分别为55oC和pH 5.0.XylA的K_m和V_(max)值分别为9.24 mg/mL和54.05 μmol/min/mL.Mn~(2+)、Zn~(2+)和斗和Mg~(2+)对XylA活性具有促进作用,而Fe~(3+)和cu~(2+)对XylA活性具有明显抑制作用.HPLC分析结果表明,XylA的水解桦木木聚糖和麸皮不溶性木聚糖的产物均为木糖至木六糖,主要产物为木三糖.

  14. 棉花黄萎病真菌Verticillium dahliae木聚糖酶基因的克隆、表达和酶学性质分析%Molecular cloning and heterologous expression of a new xylanase gene from Verticillium dahliae

    Institute of Scientific and Technical Information of China (English)

    张桂敏; 饶犇; 叶戋; 马立新; 张先恩

    2008-01-01

    [目的]从棉花黄萎病真菌Verticillium dahliae中克隆木聚糖酶基因,并在毕赤酵母中进行异源表达,研究酶学性质.[方法]通过多序列比对设计简并引物,扩增出真菌V. dahliae木聚糖酶基因片段,再采用基因组步行PCR技术获得全长木聚糖酶基因序列.经BLAST比对并结合GT-AG原则分析,该基因含有一个大小为63 bp的内含子,利用DpnI介导的缺失方法对含内含子的全长木聚糖酶基因进行剪接,获得该基因的全长cDNA.将克隆到的cDNA在毕赤酵母GS115进行了表达,重组酶经纯化后进行酶学性质分析.[结果]BLAST比对显示,该cDNA推测的氨基酸序列和已知木聚糖酶的最高一致性为72%.测得该酶最适反应温度为45℃,最适反应pH值为6,在pH5-9维持50%以上的活性,对山毛榉材木聚糖具有最好的水解效果.Mg2+和Ca2+对酶有激活作用,分别提高了33.7%和16.6%,EDTA,β-巯基乙醇和NaN3对酶的活性基本没有影响,Tween-80和DMSO使酶活性提高了28.4%和12.8%.[结论]本文从引起棉花黄萎病的真菌V. dahliae中克隆到的木聚糖酶基因是在GenBank上登录的第一个来自棉花黄萎病真菌的木聚糖酶基因序列.本文所用的克隆方法可以高效的从植物病原真菌和白腐真菌克隆只含一个内含子的11家族的新木聚糖酶基因,避免了摸索原始菌株酶表达诱导条件,检测酶的活性等繁琐的操作.酶学性质分析显示该酶在低聚木糖的制备,面包改良上有潜在的应用价值.

  15. The conditions of the liquid fermentation of pleurotus ostreatus to produce xylanase using brewer's spent grain as raw materials%利用啤酒糟液体深层培养风尾菇产木聚糖酶的初步研究

    Institute of Scientific and Technical Information of China (English)

    潘真清; 陈涛

    2010-01-01

    研究了风尾菇(Pleurotus ostreatus)利用啤酒糟作为原料进行液态发酵产木聚糖酶的可行性.通过正交试验得出最佳的培养基配方.同时对不同发酵时间还原糖的减少和木聚糖酶活性的进行测定.培养基最佳配方:啤酒糟6 g,黄豆粉0.32 g,玉米粉2 g,糖10 g,pH值5.0.发酵的最佳时间为72 h,此时木聚糖酶的活性最大,为9.2 U/mL.

  16. Purification and Properties of 43 kD Xylanase XYNA from Streptomyces olivaceoviridis A1%橄榄绿链霉菌A1所产43kD木聚糖酶XYNA的纯化及其酶学性质

    Institute of Scientific and Technical Information of China (English)

    张红莲; 姚斌; 袁铁铮; 王亚茹; 操时树; 范云六

    2002-01-01

    橄榄绿链霉菌A1(Streptomyces olivaceoviridisA1)所产木聚糖酶XYNA经阴离子交换层析和分子筛层析分离,得到纯化的XYNA.XYNA的分子量约为43 kD.其最适温度为60℃,最适pH5.6.XYNA在55℃下以4-O-Me-D-glucurono-D-xylan的Km值和Vmax分别是332 g/kg和15.72μmol/(mL@min).SDS、EDTA对XYNA有轻微的抑制作用.XYNA无纤维素酶活性.胃蛋白酶、胰蛋白酶处理30 min,对酶活性无影响.XYNA成熟蛋白N端10个氨基酸序列为Ala-G1u-Ser-Thr-Leu-Gly-Ala-A1a-Ala-Ala.

  17. 中国吐鲁番两株产木聚糖酶的极端耐碱Bacillus halodurans的分类鉴定%Isolation and identification of two xylanase-producing extremely alkali-tolerant strains of Bacillus halodurans from Turpan in China

    Institute of Scientific and Technical Information of China (English)

    易霞; 谢周杰; 邓爱华; 王宁; 艾尔肯·热合曼

    2006-01-01

    通过生理生化实验、16S rDNA 序列分析和同源性杂交,将分离到的XJU-1和XJU-80菌种进行了分类鉴定.XJU-1和XJU-80具有较宽的pH生长范围(分别是pH4.5~12.6和pH3.8~12.6),其G+C mol%含量分别是40.5mol%和42.2mol%.16S rDNA 序列分析和DNA-DNA同源杂交结果表明,XJU-1和XJU-80与Bacillus halodurans C-125和Bacillus halodurans DSM497T具有较高的同源性(99%);两者之间也具有85%的相关性,但其与Bacillus halodurans C-125和Bacillus halodurans DSM497T分别具有81.3%和71.5%的相关性.基于以上结果,将两株分离菌株分类为Bacillus halodurans的两个新品系.%Bacillus halodurans XJU-1 and XJU-80 were characterized in terms of physiological and biochemical characteristics, and 16S rDNA sequence homology and DNA-DNA hybridization analysis. The two isolates can grow in nutrient broth at a broad range of pH values from 4.5 to 12.6 for XJU-1 and from 3.8 to 12.8 for XJU-80, respectively. And the optimum temperature of growth were around 39℃and 42℃, respectively. Phylogenetic analysis of the two strains based on comparison of 16S rRNA sequence revealed that they are closely related to Bacillus halodurans C-125 and DSM497Twith 99% identity. DNA-DNA hybridization showed that the highest levels of DNA-DNA relatedness were found between the two strains (85%) and the B. Halodurans type strains (81.3% and 71.5%), respectively. Moreover, the G+C content of the genomic DNA was 40.5 mol% for XJU-1 and 42.2 mol% for XJU-80.Our results demonstrate that strains XJU-1 and XJU-80 should be classified as two new members of the species B. Halodurans.

  18. Dicty_cDB: Contig-U07109-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available -17 CP000852_1186( CP000852 |pid:none) Caldivirga maquilingensis IC-16... 82 3e-1... |pid:none) Rhodococcus jostii RHA1, comple... 39 0.15 CP000852_1418( CP000852 |pid:none) Caldivirga maqui...Anaerocellum thermophilum DSM 67... 39 0.26 CP000852_1427( CP000852 |pid:none) Caldivirga maquilingensis IC-...p. TP009 clone 4 seque... 37 0.99 CP000852_1423( CP000852 |pid:none) Caldivirga maquilingensis IC-16... 37 0...2 |pid:none) Caldivirga maquilingensis IC-16... 43 0.014 AP008226_643( AP008226 |

  19. Ancestral genetic diversity associated with the rapid spread of stress-tolerant coral symbionts in response to Holocene climate change

    OpenAIRE

    Hume, Benjamin C C; VOOLSTRA, CHRISTIAN R.; Arif, Chatchanit; D'Angelo, Cecilia; Burt, John A.; Eyal, Gal; Loya, Yossi; Wiedenmann, Jörg

    2016-01-01

    Coral communities in the Persian/Arabian Gulf (PAG) withstand unusually high salinity levels and regular summer temperature maxima of up to ?35 °C that kill conspecifics elsewhere. Due to the recent formation of the PAG and its subsequent shift to a hot climate, these corals have had only 5,000 km of the PAG, the Gulf of Oman, and the Red Sea coastline, we show that S. thermophilum is a member of a highly diverse, ancient group of symbionts cryptically distributed outside the PAG. We argue th...

  20. Ancestral genetic diversity associated with the rapid spread of stress-tolerant coral symbionts in response to Holocene climate change

    KAUST Repository

    Hume, Benjamin C. C.

    2016-04-05

    Coral communities in the Persian/Arabian Gulf (PAG) withstand unusually high salinity levels and regular summer temperature maxima of up to ∼35 °C that kill conspecifics elsewhere. Due to the recent formation of the PAG and its subsequent shift to a hot climate, these corals have had only <6, 000 y to adapt to these extreme conditions and can therefore inform on how coral reefs may respond to global warming. One key to coral survival in the world\\'s warmest reefs are symbioses with a newly discovered alga, Symbiodinium thermophilum. Currently, it is unknown whether this symbiont originated elsewhere or emerged from unexpectedly fast evolution catalyzed by the extreme environment. Analyzing genetic diversity of symbiotic algae across >5, 000 km of the PAG, the Gulf of Oman, and the Red Sea coastline, we show that S. thermophilum is a member of a highly diverse, ancient group of symbionts cryptically distributed outside the PAG. We argue that the adjustment to temperature extremes by PAG corals was facilitated by the positive selection of preadapted symbionts. Our findings suggest that maintaining the largest possible pool of potentially stress-tolerant genotypes by protecting existing biodiversity is crucial to promote rapid adaptation to present-day climate change, not only for coral reefs, but for ecosystems in general.