Pasteur's genome

Pasteurella multocida causes disease in birds, cattle, swine and humans, but the mechanisms underlying its virulence are unknown. In the 6 March PNAS May and colleagues report the complete sequence of the Pasteurella multocida (Pm70) genome (PNAS 2001, 98:3460-3465).

May et al used a shotgun strategy to sequence more than 53,000 DNA fragments and assemble them into a single circular sequence of about 2.26 Mb. The Pm70 genome contains 2,014 predicted coding regions, accounting for 89% of the entire chromosome, as well as six rRNA operons and 57 tRNA genes. About 10% of the open reading frames are unique to Pm, with more than half having orthologs in the closely related Haemophilus influenza (Hi) and also in Escherichia coli (Ec). Comparative analysis suggests that Pm diverged from Hi around 230 million years ago and from Ec around 680 millions years ago.

May et al identified 104 putative virulence-associated genes, notably ...