title: Biochemical characterization of a novel surfactant-stable serine keratinase with no collagenase activity from Brevibacillus parabrevis CGMCC 10798.
abstract: Dehairing is a high pollution process in leather industry. Conventionally, the lime-sulfide mediated chemical process for dehairing would lead to the discharge of pollutants and corrosion of industrial equipment. Concerning these problems, keratinase has become a promising candidate for dehairing process in recent years. In this study, a keratinase-producing bacterium was isolated from sheepfold soil and identified as Brevibacillus parabrevis CGMCC 10798 based on the biochemical characteristics and molecular identification. The keratinase was purified to electrophoretic homogeneity with 17.19% of recovery, 13.18 folds of purification and an estimated molecular weight of 28kDa. The enzyme exhibited high keratinase activity and no collagenase activity. Besides, the keratinase showed optimal activity at 60°C and pH 8.0. The enzyme activity could be significantly increased in the presence of Na+and Ca2+. And it was inhibited by EDTA, and PMSF, which indicated that the keratinase belongs to serine-metallo protease. The enzyme could remain stable in the presence of surfactants. Especially, 5mM Tween 40 and Triton 100 could improve the activity by 11% and 30%, respectively. Moreover, B. parabrevis keratinase could completely dehair goat wool within 7h, which indicated its application potential in leather industry.
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China; School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Rong-Xian
authors.initials: RX
authors.lastname: Zhang
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Jin-Song
authors.initials: JS
authors.lastname: Gong
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Chang
authors.initials: C
authors.lastname: Su
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Dan-Dan
authors.initials: DD
authors.lastname: Zhang
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Tian
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Dou
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
authors.forename: Heng
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China. Electronic address: shijs@163.com.
authors.forename: Jin-Song
authors.initials: JS
authors.lastname: Shi
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, PR China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China. Electronic address: zhenghxu@jiangnan.edu.cn.
authors.forename: Zheng-Hong
authors.initials: ZH
authors.lastname: Xu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification; D058675:Brevibacillus / Q000201:enzymology*; D017364:Collagenases / Q000737:chemistry; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D010447:Peptide Hydrolases / Q000737:chemistry / Q000302:isolation & purification; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D010447:Peptide Hydrolases; C035855:keratinase; D017364:Collagenases
keywords: Brevibacillus parabrevis; Dehairing; Keratinase