Exploration of the key functional proteins from an efficient cellulolytic microbial consortium using dilution-to-extinction approach  

作　　者：Qinghua Zhang Hanguang Li Xiangdong Zhu Fenju Lai Zhijun Zhai Yuanxiu Wang 

机构地区：[1]College of Bioscience and engineering, Jiangxi engineering Laboratory for the development and Utilization of Agricultural Microbial Resources,Jiangxi Agricultural University, Nanehan9 330045, China

出　　处：《Journal of Environmental Sciences》2016年第5期199-207,共9页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 31260024);the Science and Technology Support Program of Jiangxi Province (No. 20151BBF60029);the Jiangxi Province Science Foundation (Nos. 20122BAB214012, 20151BAB204001);Science and Technology Project Founded by the Education Department of Jiangxi Province (No. GJJ14297)

摘　　要：In the present study, the cellulose binding proteins（CBPs） secreted by a putative cellulolytic microbial consortium were isolated and purified by affinity digestion. The purified CBPs were subsequently separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis（SDS-PAGE）. Using mass spectrometric analyses, eight CBPs were identified and annotated to be similar to known proteins secreted by Clostridium clariflavum DSM 19732 and Paenibacillus sp. W-61. In addition, in combination with dilution-to-extinction approach and zymogram analysis technique, CBPs 6（97 k Da） and 12（52 k Da） were confirmed to be the key functional proteins that influence cellulolytic activities. Moreover, structural domain analyses and enzymatic activity detection indicated that CBPs 6 and 12 contained glycoside hydrolase families（GH） 9 and 48 catalytic modules, which both revealed endoglucandase and xylanase activities. It was suggested that the coexistence of GH9 and GH48 catalytic domains present in these two proteins could synergistically promote the efficient degradation of cellulose.In the present study, the cellulose binding proteins（CBPs） secreted by a putative cellulolytic microbial consortium were isolated and purified by affinity digestion. The purified CBPs were subsequently separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis（SDS-PAGE）. Using mass spectrometric analyses, eight CBPs were identified and annotated to be similar to known proteins secreted by Clostridium clariflavum DSM 19732 and Paenibacillus sp. W-61. In addition, in combination with dilution-to-extinction approach and zymogram analysis technique, CBPs 6（97 k Da） and 12（52 k Da） were confirmed to be the key functional proteins that influence cellulolytic activities. Moreover, structural domain analyses and enzymatic activity detection indicated that CBPs 6 and 12 contained glycoside hydrolase families（GH） 9 and 48 catalytic modules, which both revealed endoglucandase and xylanase activities. It was suggested that the coexistence of GH9 and GH48 catalytic domains present in these two proteins could synergistically promote the efficient degradation of cellulose.

关 键 词：Microbial consortium Cellulolytic Cellulose binding protein Dilution-to-extinction approach 

分 类 号：Q936[生物学—微生物学]