Genomic evidence for the evolution of Streptococcus equi: host restriction, increased virulence, and genetic exchange with human pathogens. by Holden, M, Heather, Z, Paillot, R, Steward, K, Webb, K, Ainslie, F, Jourdan, T, Bason, N, Holroyd, N, Mungall, K, Quail, M, Sanders, M, Simmonds, M, Willey, D, Brooks, K, Aanensen, D, Spratt, BG, Jolley, K, Maiden, M, Kehoe, M, Chanter, N, Bentley, S, Robinson, C, Maskell, D, Parkhill, J, Waller, A