Genetic structure of Salmonella revealed by fragment analysis.

Recently, the genus Salmonella has been studied by multilocus enzyme electrophoresis (MLEE) and three collections of strains defined by this method, SARA, SARB and SARC, have been assembled to represent the genetic diversity of Salmonella choleraesuis (commonly known as Salmonella enterica) subspecies I and of the genus as a whole. The novel technique fluorescent amplified-fragment length polymorphism (FAFLP) analysis was applied to these collections to determine the genetic diversity of Salmonella. FAFLP broadly confirmed the MLEE findings but added precision to them, successfully distinguishing between the subspecies of S. enterica. It revealed the clonal nature of some serotypes of S. enterica subspecies I and the diversity of others. The enteric Salmonella Paratyphi B strains clustered separately from those associated with gastroenteritis. FAFLP is a powerful, highly flexible, whole-genome method that can be used to provide an unweighted view of genetic variation within Salmonella.