Shigella boydii CDC 3083-94

Shigella is a Gram-negative, non-sporulating, facultative anaerobe bacterium that causes dysentery or shigellosis in man. Shigella are highly invasive in the colon and the rectum, and are able to proliferate in the host cell cytoplasm, triggering an inflammatory reaction. Shigella was recognized as the etiologic agent for bacillary dysentery in the 1890's, and adopted as a genus in the 1950's and subgrouped into four species. However, a recent genetic study argues that Shigella emerged from multiple independent origins of E.coli 35,000-270,000 years ago and may not constitute a genus. S.boydii is mainly epidemic to the Indian subcontinent. Comparison of 20 E.coli/Shigella strains shows the core genome to be about 2000 genes while the pan-genome has over 18,000 genes. There are multiple, striking integration hotspots that are conserved across the genomes, corresponding to regions of abundant and parallel insertions and deletions of genetic material.Shigella boydii BS512 was originally isolated from a 12-year-old boy in Arizona, USA. It is serotype 18 and is a member of Group 1 as determined by sequence analysis. The virulence of S. boydii BS512 has been verified through in vitro experimentation via invasion of HeLa cells. (HAMAP: SHIB3)