1. Center for Anaerobic Microbial Resources of Sichuan Province, Chengdu 610041, PR China
2. Key Laboratory of Development and Application of Rural Renewable Energy, Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, Sichuan Province, PR China
3. National Agricultural Experimental Station for Microorganisms, Shuangliu, Chengdu 610213, Sichuan Province, PR China