Cloning, expression and characterization of a cold-adapted endo-1, 4- β -glucanase from Citrobacter farmeri A1, a symbiotic bacterium of Reticulitermes labralis

PeerJ

article

Xi Bai¹  Xianjun Yuan¹  Aiyou Wen²  Junfeng Li¹  Yunfeng Bai³  Tao Shao¹ 

[1] Institute of Ensiling and Processing of Grass, Nanjing Agricultural University;College of Animal Science, University of Science and Technology of Anhui;Institute of Agricultural Resource and Environment, Jiangsu Academy of Agricultural Sciences

关键词: Citrobacter farmeri;    Endoglucanase;    Cold-adapted;    Expression;    Escherichia coli;    Properties;   

DOI  :  10.7717/peerj.2679

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundMany biotechnological and industrial applications can benefit from cold-adapted EglCs through increased efficiency of catalytic processes at low temperature. In our previous study, Citrobacter farmeri A1 which was isolated from a wood-inhabiting termite Reticulitermes labralis could secrete a cold-adapted EglC. However, its EglC was difficult to purify for enzymatic properties detection because of its low activity (0.8 U/ml). The objective of the present study was to clone and express the C. farmeri EglC gene in Escherichia coli to improve production level and determine the enzymatic properties of the recombinant enzyme.MethodsThe EglC gene was cloned from C. farmeri A1 by thermal asymmetric interlaced PCR. EglC was transformed into vector pET22b and functionally expressed in E. coli. The recombination protein EglC22b was purified for properties detection.ResultsSDS-PAGE revealed that the molecular mass of the recombinant endoglucanase was approximately 42 kDa. The activity of the E. coli50% relative activity even at 5 °C, whereas it lost approximately 90% of its activity after incubation at 60 °C for 30 min. Its activity was enhanced by Co2+ and Fe3+, but inhibited by Cd2+, Zn2+, Li+, Triton X-100, DMSO, acetonitrile, Tween 80, SDS, and EDTA.ConclusionThese biochemical properties indicate that the recombinant enzyme is a cold-adapted endoglucanase that can be used for various industrial applications.

【 授权许可】

CC BY