Proposal that the strains of the Mycoplasma ovine/caprine serogroup 11 be reclassified as Mycoplasma bovigenitalium.

This proposal is our response to the recommendation of the International Committee on Systematics of Prokaryotes (Subcommittee on the taxonomy of Mollicutes) that we 'write a proposal to classify Mycoplasma bovigenitalium and ovine/caprine serogroup 11 as a single species'. Physiological and phylogenetic comparisons between 27 strains of M. bovigenitalium and Mycoplasma serogroup 11 showed that (i) growth and patterns of organic acid substrate use completely overlapped among strains; (ii) all had lipase and phosphatase activities; (iii) the strains were indistinguishable in their SDS-PAGE whole-cell protein profiles, which differed from five other species; (iv) strains were indistinguishable in immunoblotting of cell proteins and cross-reactivity in ELISA, but differed from other Mycoplasma species; (v) DNA-DNA hybridization did not distinguish between the two groups, and (vi) comparison of 16S and 23S rRNA gene sequences of ten strains of Mycoplasma serogroup 11 and six strains of M. bovigenitalium showed that they shared 98-100% similarity across all strains tested, but only 86-95% to other Mycoplasma species. Strains of the Mycoplasma ovine/caprine serogroup 11 must therefore be reassigned as Mycoplasma bovigenitalium.