1. Department of Biology, University of York, PO Box 373, York Y01 5YW, UK
2. Department of Applied Chemistry and Microbiology, Biocenter 1, PO Box 56, FIN-00014, University of Helsinki, Finland
3. Key Laboratory of Agro-Microbial Resources and Application, Ministry of Agriculture of China, College of Biological Sciences, China Agricultural University, Beijing 100094, China
4. Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México D.F. 11340, Mexico
5. Department of Molecular Genetics, College of Agronomy, South China Agricultural University, Guangzhou 510642, China