1. Molecular Evolution and Bioinformatics Section, Mansfield Road, Oxford Centre for Ecology and Hydrology, Oxford OX1 3SR, United Kingdom
2. Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
3. School of Computer Science, University of Manchester, Manchester, UK
4. The NERC Environmental Bioinformatics Centre, Oxford Centre for Ecology and Hydrology, Oxford, UK
5. The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA
6. EMBL Outstation — The European Bioinformatics Institute (EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK
7. National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD 20894, USA
8. The Pathogen Sequencing Unit, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK