Shigella dysenteriae Sd197

Names Shigella dysenteriae Sd197
Accession numbers NC_007606, NC_007607, NC_009344
Background 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. 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 dysenteriae causes deadly epidemics in many of the poorer countries of the world. Shigella dysenteriae (strain Sd197) was isolated from epidemics in China during the 1950's. It harbors one chromosome and one plasmid. The IS-element IS1N is copiously present in the chromosome. The SHI-1, SHI-2 and SHI-3 pathogenicity islands are absent from Sd197. It has lost flagellar function due to muations in several different genes. (HAMAP: SHIDS)
Strain Sd197
Complete Yes
Sequencing centre (29-OCT-2004) State Key Laboratory for Moleclular Virology and Genetic Engineering, Microbial Genome Center of
(30-NOV-2005) National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA
Sequencing quality Level 6: Finished
Sequencing depth NA
Sequencing method NA
Isolation site Epidemic in China in 1950s
Isolation country China
Number of replicons 3
Gram staining properties Negative
Shape Bacilli
Mobility No
Flagellar presence No
Number of membranes 2
Oxygen requirements Facultative
Optimal temperature 37.0
Temperature range Mesophilic
Habitat HostAssociated
Biotic relationship Free living
Host name Homo sapiens
Cell arrangement Pairs, Singles
Sporulation Nonsporulating
Metabolism NA
Energy source Chemoorganotroph
Diseases Dysentery
Pathogenicity Yes