Plasmid content in different serovars of Salmonella isolated in Sicily: an ecology study

This study determined plasmid relative abundance and distribution among a representative collection of Sicilian strains of Salmonella, with the purpose of gaining more insight into bacterial and plasmid ecology. 161 Salmonella strains of different serovars, isolated in Sicily from human and environmental sources between 1981 and 1985 were characterized by plasmid profile typing. Two main sets of Salmonella serovars were identified, one composed by plasmid-free serovars, rarely associated with clinical salmonellosis but typical of environmental niches; the other comprising the serovars usually encountered as major agents of human and animal salmonellosis. The biological relevance of the baseline information so provided on the genetic profiles of different serovars in Sicily is discussed.