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Glycoside hydrolase

Federico Sabbadin, Giovanna Pesante, Luisa Elias, Katrin Besser, Yi Li, Clare Steele-King, Meg Stark, Deborah A Rathbone, Adam A Dowle, Rachel Bates, J Reuben Shipway, Simon M Cragg, Neil C Bruce, Simon J McQueen-Mason
Lignocellulose forms the structural framework of woody plant biomass and represents the most abundant carbon source in the biosphere. Turnover of woody biomass is a critical component of the global carbon cycle, and the enzymes involved are of increasing industrial importance as industry moves away from fossil fuels to renewable carbon resources. Shipworms are marine bivalve molluscs that digest wood and play a key role in global carbon cycling by processing plant biomass in the oceans. Previous studies suggest that wood digestion in shipworms is dominated by enzymes produced by endosymbiotic bacteria found in the animal's gills, while little is known about the identity and function of endogenous enzymes produced by shipworms...
2018: Biotechnology for Biofuels
Kai Tang, Yao Zhang, Dan Lin, Yu Han, Chen-Tung A Chen, Deli Wang, Yu-Shih Lin, Jia Sun, Qiang Zheng, Nianzhi Jiao
Shallow-sea hydrothermal systems experience continuous fluctuations of physicochemical conditions due to seawater influx which generates variable habitats, affecting the phylogenetic composition and metabolic potential of microbial communities. Until recently, studies of submarine hydrothermal communities have focused primarily on chemolithoautotrophic organisms, however, there have been limited studies on heterotrophic bacteria. Here, fluorescence in situ hybridization, high throughput 16S rRNA gene amplicon sequencing, and functional metagenomes were used to assess microbial communities from the shallow-sea hydrothermal system off Kueishantao Island, Taiwan...
2018: Frontiers in Microbiology
Thi Huyen Do, Ngoc Giang Le, Trong Khoa Dao, Thi Mai Phuong Nguyen, Tung Lam Le, Han Ly Luu, Khanh Hoang Viet Nguyen, Van Lam Nguyen, Lan Anh Le, Thu Nguyet Phung, Nico M van Straalen, Dick Roelofs, Nam Hai Truong
The scarcity of enzymes having an optimal activity in lignocellulose deconstruction is an obstacle for industrial-scale conversion of cellulosic biomass into biofuels. With the aim of mining novel lignocellulolytic enzymes, a ~9 Gb metagenome of bacteria in Vietnamese native goats' rumen was sequenced by Illumina platform. From the data, 821 ORFs encoding carbohydrate esterases (CEs) and polysaccharide lyases (PLs) serving for lignocellulose pre-treatment, 816 ORFs encoding 11 glycoside hydrolase families (GHs) of cellulases, and 2252 ORFs encoding 22 GHs of hemicellulases, were mined...
March 12, 2018: Journal of General and Applied Microbiology
Lu Cai, Tong-Bin Chen, Sheng-Wei Zheng, Hong-Tao Liu, Guo-Di Zheng
Sewage sludge biodrying is a waste treatment method that uses bio-heat generated from organic degradation to remove moisture from sewage sludge. Lignocellulose and carbohydrate decomposition is important when assessing biodrying performance. This study investigated lignocellulose and carbohydrate decomposition, and the potential microbial functions during biodrying. We determined the lignocellulose and carbohydrate contents, assayed related enzyme activity, performed a complete metagenomic study on sewage sludge biodrying material during the thermophilic phase, annotated potential genetic function involved in the decomposition, and summarized the key metabolic pathways...
February 28, 2018: Chemosphere
Houhou Huang, Fei Han, Shanshan Guan, Mengdan Qian, Yongfeng Wan, Yaming Shan, Hao Zhang, Song Wang
Glycoside hydrolase cellulase family 6 from Trichoderma reesei (TrCel6A) is an important cellobiohydrolase to hydrolyze cellooligosaccharide into cellobiose. The knowledge of enzymatic mechanisms is critical for improving the conversion efficiency of cellulose into ethanol or other chemicals. However, the process of product expulsion, a key component of enzymatic depolymerization, from TrCel6A has not yet been described in detail. Here, conventional molecular dynamics and steered molecular dynamics (SMD) were applied to study product expulsion from TrCel6A...
March 8, 2018: Journal of Biomolecular Structure & Dynamics
Francesca Anna Fusco, Gabriella Fiorentino, Emilia Pedone, Patrizia Contursi, Simonetta Bartolucci, Danila Limauro
Dtur_0462 gene from the hypertermophilic bacterium Dictyoglomus turgidum, encoding a β-glucosidase, was synthetically produced and expressed in Escherichia coli BL21(DE3)-RIL. DturβGlu was purified to homogeneity by affinity chromatography and its homotetrameric structure was determined by gel filtration. The monomer is composed by 418 amino acidic residues and showed high sequence similarity with Glycoside Hydrolases (GHs) belonging to GH1 family. The maximum activity of DturβGlu was observed at 80 °C and at pH 5...
March 5, 2018: International Journal of Biological Macromolecules
Pearl Z Fernandes, Marija Petricevic, Lukasz Sobala, Gideon J Davies, Spencer John Williams
Endo-α-1,2-mannosidases and -mannanases, members of glycoside hydrolase family 99 (GH99), cleave α-Glc/Man-1,3-α-Man-OR structures within mammalian N-linked glycans and fungal α-mannan, respectively. They are proposed to act through a two-step mechanism involving a 1,2-anhydrosugar 'epoxide' intermediate, involving two conserved catalytic residues. In the first step Glu333 acts as general base to deprotonate the 2-hydroxyl group adjacent to the fissile glycosidic bond, while Glu336 provides general acid assistance to departure of the aglycon...
March 5, 2018: Chemistry: a European Journal
Xing Qin, Xiaoyun Su, Huiying Luo, Rui Ma, Bin Yao, Fuying Ma
Background: Irpex lacteus is one of the most potent white rot fungi for biological pretreatment of lignocellulose for second biofuel production. To elucidate the underlying molecular mechanism involved in lignocellulose deconstruction, genomic and transcriptomic analyses were carried out for I. lacteus CD2 grown in submerged fermentation using ball-milled corn stover as the carbon source. Results: Irpex lacteus CD2 efficiently decomposed 74.9% lignin, 86.3% cellulose, and 83...
2018: Biotechnology for Biofuels
Zhen Qin, Qiming Chen, Si Lin, Sa Luo, Yongjun Qiu, Liming Zhao
Chitooligosaccharide is widely used as a functional food additive and a valuable pharmacological agent. The transformation of chitinous biomass into valuable bioactive chitooligosaccharides is one of the most exciting applications of chitosanase. A novel glycoside hydrolase (GH) family 46 chitosanase (GsCsn46A) from rhizobacterium Gynuella sunshinyii was cloned and heterologously expressed in Escherichia coli. GsCsn46A showed maximal activity at pH 5.5 and 30 °C. GsCsn46A featured remarkable cold-adapted property, which controllably hydrolyzed chitosan to three types of chitooligosaccharides at the mild reaction condition (reaction condition: pH 5...
July 1, 2018: Food Chemistry
Yifan Bu, Yinglu Cui, Ying Peng, Meirong Hu, Yu'e Tian, Yong Tao, Bian Wu
Xylanases, which cleave the β-1,4-glycosidic bond between xylose residues to release xylooligosaccharides (XOS), are widely used as food additives, animal feeds, and pulp bleaching agents. However, the thermally unstable nature of xylanases would hamper their industrial application. In this study, we used in silico design in a glycoside hydrolase family (GH) 11 xylanase to stabilize the enzyme. A combination of the best mutations increased the apparent melting temperature by 14 °C and significantly enhanced thermostability and thermoactivation...
March 2, 2018: Applied Microbiology and Biotechnology
Pornpimol Phuengmaung, Daisuke Fujiwara, Wasana Sukhumsirichart, Tatsuji Sakamoto
In previous reports, we characterized four endo-xylanases produced by Streptomyces sp. strain SWU10 that degrade xylans to several xylooligosaccharides. To obtain a set of enzymes to achieve complete xylan degradation, a β-d-xylosidase gene was cloned and expressed in Escherichia coli, and the recombinant protein, named rSWU43A, was characterized. SWU43A is composed of 522 amino acids and does not contain a signal peptide, indicating that the enzyme is an intracellular protein. SWU43A was revealed to contain a Glyco_hydro_43 domain and possess the three conserved amino acid residues of the glycoside hydrolase family 43 proteins...
May 2018: Enzyme and Microbial Technology
Pornpimol Phuengmaung, Yuika Kunishige, Wasana Sukhumsirichart, Tatsuji Sakamoto
We previously described thermotolerant Streptomyces sp. SWU10, which produced four endo-xylanases and one xylosidase able to digest xylan backbones. To achieve arabinoxylan degradation, the swu62A gene was cloned and overexpressed in Escherichia coli, and the recombinant enzyme, termed SWUAbf62A, was characterized. The 438 amino acids of SWUAbf62A revealed Glyco_hydro_62 and closely related with putative α-l-arabinofuranosidases belonging to glycoside hydrolase family 62. SWUAbf62A was purified in two steps, Ni-affinity and size-exclusion column chromatographies, and its molecular mass without signal peptide was determined to be 49 kDa...
May 2018: Enzyme and Microbial Technology
Chunjuan He, Yirui Yang, Renfei Zhao, Jingyao Qu, Lan Jin, Lili Lu, Li Xu, Min Xiao
Levansucrases, which belong to the glycoside hydrolase family 68 (GH68), synthesize β (2-6)-linked fructan levan with sucrose as substrate. We described the use of a levansucrase (Bl_SacB) from Bacillus licheniformis 8-37-0-1 for catalysis of fructosyl transfer to obtain high levan yield previously. In the present study, six variants (Y246A, N251A, K372A, R369A, R369S, and R369K) were constructed through sequence alignment and structural analysis to explore the synthesis mechanism of Bl_SacB. The selected residues were predicted to localize to the substrate-entering channel of the active cavity and close to or remote from the catalytic triad...
March 1, 2018: Applied Microbiology and Biotechnology
Jianfeng Wang, Zhongmei Liu, Zhemin Zhou
Anoxybacillus sp. WB42 pullulanase (PulWB42) is a novel thermophilic amylopullulanase which is assigned to the glycoside hydrolase family 13 subfamily 14 (GH13_14) type I pullulanases in the carbohydrate-active enzymes database. Its N-terminal domain (Met1-Phe101) was identified as the carbohydrate-binding module 68 (CBM68) via homology modeling. The N-domain-deleted PulWB42 exhibited an equivalent Km for pullulan and significant decreases in pullulytic activity, amylose selectivity, and thermostability as compared to PulWB42 having high alpha-amylase-to-pullulanase activity ratio...
March 1, 2018: Chembiochem: a European Journal of Chemical Biology
Xiangyun Zang, Meiting Liu, Yihong Fan, Jie Xu, Xiuhong Xu, Hongtao Li
Background: Compost habitats sustain a vast ensemble of microbes that engender the degradation of cellulose, which is an important part of global carbon cycle. β-Glucosidase is the rate-limiting enzyme of degradation of cellulose. Thus, analysis of regulation of β-glucosidase gene expression in composting is beneficial to a better understanding of cellulose degradation mechanism. Genetic diversity and expression of β-glucosidase-producing microbial communities, and relationships of cellulose degradation, metabolic products and the relative enzyme activity during natural composting and inoculated composting were evaluated...
2018: Biotechnology for Biofuels
Andre S Godoy, Caroline S Pereira, Marina Paglione Ramia, Rodrigo L Silveira, Cesar M Camilo, Marco A Kadowaki, Lene Lange, Peter K Busk, Alessandro S Nascimento, Munir S Skaf, Igor Polikarpov
The glycoside hydrolase family 45 (GH45) of carbohydrate modifying enzymes is mostly comprised of β-1,4-endoglucanases. Significant diversity between the GH45 members has prompted the division of this family into three subfamilies: A, B and C, which may differ in terms of the mechanism, general architecture, substrate binding and cleavage. Here, we use a combination of X-ray crystallography, bioinformatics, enzymatic assays, molecular dynamics simulations and site-directed mutagenesis experiments to characterize the structure, substrate binding and enzymatic specificity of the GH45 subfamily C endoglucanase from Phanerochaete chrysosporium (PcCel45A)...
February 27, 2018: Scientific Reports
Shimpei Aikawa, Sirilak Baramee, Junjarus Sermsathanaswadi, Phakhinee Thianheng, Chakrit Tachaapaikoon, Ayumi Shikata, Rattiya Waeonukul, Patthra Pason, Khanok Ratanakhanokchai, Akihiko Kosugi
An anaerobic, cellulolytic-xylanolytic bacterium, designated strain A7, was isolated from a cellulose-degrading bacterial community inhabiting bovine manure compost on Ishigaki Island, Japan, by enrichment culture using unpretreated corn stover as the sole carbon source. The strain was Gram-positive, non-endospore forming, non-motile, and formed orange colonies on solid medium. Strain A7 was identified as Herbivorax saccincola by DNA-DNA hybridization, and phylogenetic analysis based on 16S rRNA gene sequences showed that it was closely related to H...
February 11, 2018: Systematic and Applied Microbiology
Katarína Šuchová, Stanislav Kozmon, Vladimír Puchart, Anna Malovíková, Tine Hoff, Kristian B R Mørkeberg Krogh, Peter Biely
XynA from Erwinia chrysanthemi (EcXyn30A), belonging to glycoside hydrolase family 30 subfamily 8, is specialized for hydrolysis of 4-O-methylglucuronoxylan (GX). Carboxyl group of 4-O-methylglucuronic acid serves as a substrate recognition element interacting ionically with positively charged Arg293 of the enzyme. We determined kinetic parameters of EcXyn30A on GX, its methyl ester (GXE) and 4-O-methylglucoxylan (GXR) and compared them with behavior of the enzyme variant in which Arg293 was replaced by Ala...
February 22, 2018: Archives of Biochemistry and Biophysics
Laura L Lee, Sara E Blumer-Schuette, Javier A Izquierdo, Jeffrey V Zurawski, Andrew J Loder, Jonathan M Conway, James G Elkins, Mircea Podar, Alicia Clum, Piet C Jones, Marek J Piatek, Deborah A Weighill, Daniel A Jacobson, Michael W W Adams, Robert M Kelly
Metagenomic data from Obsidian Pool (Yellowstone National Park, USA) and thirteen genome sequences were used to re-assess genus-wide biodiversity for the extremely thermophilic Caldicellulosiruptor The updated core-genome contains 1,401 ortholog groups (average genome size for thirteen species = 2,516 genes). The pan-genome, which remains open with a revised total of 3,493 ortholog groups, encodes a variety of multi-domain glycoside hydrolases (GH). These include three cellulases with GH48 domains that are co-located in the Glucan Degradation Locus (GDL) and are specific determinants for microcrystalline cellulose utilization...
February 23, 2018: Applied and Environmental Microbiology
Ming-Wei Lai, Ruey-Fen Liou
Plant cell walls are pivotal battlegrounds between microbial pathogens and their hosts. To penetrate the cell wall and thereby to facilitate infection, microbial pathogens are equipped with a wide array of cell wall-degrading enzymes to depolymerize the polysaccharides in the cell wall. However, many of these enzymes and their role in the pathogenesis of microbial pathogens are not characterized, especially those from Oomycetes. In this study, we analyzed the function of four putative endo-beta-1,4-xylanase-encoding genes (ppxyn1-ppxyn4) from Phytophthora parasitica, an oomycete plant pathogen known to cause severe disease in a wide variety of plant species...
February 22, 2018: Current Genetics
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