---

Date of divergence of Escherichia coli and Salmonella enterica

Range	~140 Mya
Organism	bacteria
Reference	Wang L, Reeves PR. The Escherichia coli O111 and Salmonella enterica O35 gene clusters: gene clusters encoding the same colitose-containing O antigen are highly conserved. J Bacteriol. 2000 Sep182(18):5256-61. p.5256 right column bottom paragraphPubMed ID10960113
Primary Source	Ochman H, Wilson AC. Evolution in bacteria: evidence for a universal substitution rate in cellular genomes. J Mol Evol. 1987 26(1-2):74-86 AND Ochman, H., and A. C. Wilson. 1987. Evolutionary history of enteric bacteria, p. 1649–1654. In F. C. Neidhardt, J. L. Ingraham, K. B. Low, B. Magasanik, M. Schaechter, and H. E. Umbarger (ed.), Escherichia coli and Salmonella typhimurium: cellular and molecular biology, vol. 2. American Society for Microbiology, Washington, D.C.PubMed ID3125340
Method	P.5256 right column bottom paragraph: "[Investigators] present here the genetic basis for the identity of O antigens shared between S. enterica O35 and E. coli O111."
Comments	P.5256 right column bottom paragraph: "It is believed that E. coli and S. enterica diverged from a common ancestor about 140 million years ago (primary sources). The very small proportion of O antigens common to both suggests that most of the polymorphism arose after the divergence." Mya=million years ago. Range of 120–160 million years ago given in PMID 18437222 p.1 left column top paragraph
Entered by	Uri M
ID	107087