RESUMEN
A novel genomic island (GI) in Streptococcus suis serotype 2(SS2) was identified, which resided in the highly virulent strains but not in the hypo-virulent strains or avirulent strains of SS2 of the Chinese isolates. This newly discovered GI strain was designated as SSGI4 and its whole length of genome was 11 269 bps, sharing the typical properties of pathogenicity islands, such as the distinct G+C content, a mosaic architecture characteristics and the specificity for virulent isolates. There were 11 genes within SSGI4, in which some genes were putative cell surface protein genes and others were amino acid-binding protein genes. Our finding sheds light on the investigation of horizontal gene transfer in SS2 and their influence on pathogenicity.