title: Polymorphism of rRNA genes and plasmid analysis in the typing of Salmonella enterica serovar enteritidis from a Spanish health area.
abstract: A molecular epidemiological study of Salmonella enterica serovar Enteritidis (S. enteritidis) in a Spanish Health Area was carried out using two genotypic methods; polymorphism of rRNA genes (ribotyping) and plasmid analysis. The series included 100 isolates randomly selected from among those collected over the period 1984-92 (50 from sporadic episodes and 50 from 10 outbreaks). Ribotyping using HindIII, SmaI, and EcoRI showed a notable degree of homogeneity within Enteritidis serovar, it being able to discriminate only 1, 2, and 3 ribotypes, respectively. Such data suggest that there are a limited number of types or clonal lines, of which only one was widely disseminated within the health area under study (including 90% of isolates from sporadic episodes and all of those from outbreaks). Twelve plasmid profiles were differentiated. Sixty isolates carried only the virulence plasmid of 36 Md; whereas 24 isolates, grouped into 10 profiles, carried the 36 Md together with other plasmids; 7 isolates carried only other plasmids and 9 isolates were plasmid free. The combination of results from both methods revealed 15 subtypes, 9 of these including two or more isolates, one subtype being endemic and predominant (54% of the sporadic isolates and isolates from 6 outbreaks).
authors.affiliation: Departamento de Biologia Functional, Universidad de Oviedo, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Gonzalez Hevia
authors.forename: M C
authors.initials: MC
authors.lastname: Mendoza
mesh_terms: D015373:Bacterial Typing Techniques; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D005798:Genes, Bacterial; D006801:Humans; D017720:Molecular Epidemiology; D010957:Plasmids / Q000235:genetics*; D011110:Polymorphism, Genetic; D012329:RNA, Bacterial / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics*; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology; D012477:Salmonella enteritidis / Q000145:classification* / Q000235:genetics* / Q000472:pathogenicity; D012703:Serotyping; D013030:Spain / Q000453:epidemiology; D014774:Virulence / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D004262:DNA Restriction Enzymes