title: Characterization of a highly thermostable glycoside hydrolase family 10 xylanase from Malbranchea cinnamomea.
abstract: A thermostable xylanase (McXyn10) from the thermophilic fungus Malbranchea cinnamomea strain S168 was purified and biochemically characterized. The enzyme was purified to homogeneity with a molecular mass of 43.5 kDa on SDS-PAGE. The optimal pH and temperature of the purified enzyme were pH 6.5 and 80°C, respectively. The enzyme showed a broad range of pH stability (pH 4.0-10.5), and was stable up to 70°C with a thermal denaturing half life of 76.0 min. The enzyme exhibited strict specificity for various xylans as substrates, but displayed no activity toward other tested polysaccharides. McXyn10 hydrolyzed birchwood xylan, beechwood xylan and oat-spelt xylan, yielded mainly xylobiose, xylotriose and xylooligosaccharides with degree of polymerization (DP) above 5, while yielded xylobiose from xylotriose and xylotetraose. The xylanase gene was further cloned. It had an open reading frame of 1191 bp with two introns. The deduced amino acid sequence of the gene showed highest identity (58%) with a glycoside hydrolase family 10 xylanase from Aureobasidium pullulans.
authors: College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
authors: Guangsen
authors: G
authors: Fan
authors: College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
authors: Shaoqing
authors: S
authors: Yang
authors: Bioresource Utilization Laboratory, College of Engineering, China Agricultural University, Beijing 100083, China.
authors: Qiaojuan
authors: Q
authors: Yan
authors: College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
authors: Yu
authors: Y
authors: Guo
authors: College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China.
authors: Yanxiao
authors: Y
authors: Li
authors: College of Food Science and Nutritional Engineering, Beijing Key Laboratory of Functional Food from Plant Resources, China Agricultural University, Beijing 100083, China. Electronic address: zhqjiang@cau.edu.cn.
authors: Zhengqiang
authors: Z
authors: Jiang
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000201:enzymology*; D001483:Base Sequence; D003001:Cloning, Molecular; D004789:Enzyme Activation; D004795:Enzyme Stability; D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D006026:Glycoside Hydrolases
keywords: M. cinnamomea; Thermostable xylanase; Xylooligosaccharides