title: Two neutral thermostable cellulases from Phialophora sp. G5 act synergistically in the hydrolysis of filter paper.
abstract: Two novel cellulase genes, cbh6A and egGH45, were cloned from Phialophora sp. G5 and successfully expressed in Pichia pastoris. The putative polypeptide of CBH6A consists of a family 1 CBM and a catalytic domain of glycosyl hydrolase family 6 cellobiohydrolases, while deduced EgGH45 only contains a catalytic domain of family 45 endoglucanases. CBH6A and EgGH45 were optimally active at pH 7.0 and 65°C, and pH 6.0 and 60°C, respectively. Both enzymes exhibited high activities and stabilities over a wide pH range and had good thermostability at 70°C. CBH6A and EgGH45 had significant resistance to SDS (10mM), remaining 35% and 54% activities, respectively. These enzymes had synergic effect on the hydrolysis of filter paper, showing the highest efficiency in the ratio of CBH6A to EgGH45 at 80:20. The properties make this enzyme combination potential for application in textile and detergents industries.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
authors.forename: Junqi
authors.initials: J
authors.lastname: Zhao
authors.forename: Pengjun
authors.initials: P
authors.lastname: Shi
authors.forename: Zhongyuan
authors.initials: Z
authors.lastname: Li
authors.forename: Peilong
authors.initials: P
authors.lastname: Yang
authors.forename: Huiying
authors.initials: H
authors.lastname: Luo
authors.forename: Yingguo
authors.initials: Y
authors.lastname: Bai
authors.forename: Yaru
authors.initials: Y
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
mesh_terms: D001483:Base Sequence; D044602:Cellulases / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D019295:Computational Biology; D004591:Electrophoresis, Polyacrylamide Gel; D005374:Filtration / Q000295:instrumentation; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008969:Molecular Sequence Data; D010209:Paper; D010676:Phialophora / Q000201:enzymology*; D010843:Pichia; D017434:Protein Structure, Tertiary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D044602:Cellulases