Molecular genotype analysis of Salmonella bovismorbificans.

Genotypes were analysed within 30 isolates of Salmonella bovismorbificans from human or bovine salmonellosis and from environmental or food sources. Three clonal evolutionary lines (chromosomal genotypes) were identified on the basis of restriction fragment length polymorphism at the 16S rRNA genes, total protein profiles, and the location and copy number of a Salmonella-specific DNA insertion sequence, IS200. The predominant type was found with and without a 90 kbp plasmid homologous to the spv BC genes of S. typhimurium, and seven plasmid profiles were observed in this chromosomal genotype. This is the first such virulence plasmid to be reported in S. bovismorbificans. One example was found of two other clones which differed substantially from the predominant clone and from each other in chromosomal genotype. These results show that three clonal lines share the antigen profile of S. bovismorbificans, and provide a subtyping scheme for this serovar.