1. State Key Laboratory of Microbial Technology, Shandong University, Qingdao, P. R. China
2. College of Veterinary Medicine, Shanxi Agr icultural University, Taigu, China
3. State Key Laboratory of Desert and Oasis Ecology, Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Ürűmqi, P. R. China
4. College of Life Sciences, Hebei University, Baoding, P. R. China
5. State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China