Genome sequencing of Coxiella burnetii strain RSA439

Genome sequencing of Coxiella burnetii strain RSA439. Strain name: RSA439, synonym Nine Mile phase II, clone 4 (NMII). It is an aviulent phase variant that has been created in a laboratory, so I would call it a lab strain, but there is no official strain collection. The strain was derived from the Nine Mile phase I strain, which was originally isolated in 1935 from the tick Dermacentor andersoni in Montana, USA. The Nine Mile strain was passaged 94 times in embryonated hen’s eggs and then plaque purified to generate NMII. NMII has an ~26-kb chromosomal deletion that eliminates several LPS biosynthetic genes and is associated with the production of a severely truncated LPS. Because of clonality, avirulence in a guinea pig model of infection, and lack of phase reversion, NMII is considered a biosafety level 2 (BSL-2) bacterium.