Molecular epidemiology of plasmid patterns in Shigella flexneri types 1-6.
A total of 123 drug-resistant and drug-sensitive Shigella flexneri types 1-6, and their Escherichia coli K12 transconjugants were used for plasmid profile analysis by agarose gel electrophoresis. Resistance factors (R-factors) were further characterized by incompatibility testing. The overall distribution of small plasmids in S. flexneri showed that a cryptic plasmid of about 4.6 Kb was found in all serotypes, and a plasmid of about 4.2 Kb was found in serotypes 1-4. Shigella flexneri types 2, 4 and 6 showed a 6.5 Kb plasmid which correlated with SSu-resistance. All S. flexneri serotypes harboured large plasmids of about 217 Kb. Plasmid profile analysis of S. flexneri in Ethiopia showed a high degree of uniformity within individual serotypes. However, there was a limited variability which, at times, could be useful for epidemiological investigation. Shigella flexneri serotypes 1-6 harboured resistance plasmids with diverse molecular weights but mostly belonging to incompatibility groups N and X.
National Research Institute of Health, Addis Ababa, Ethiopia.
A
A
Gebre-Yohannes
B S
BS
Drasar
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004269:DNA, Bacterial / Q000032:analysis / Q000737:chemistry; D004352:Drug Resistance, Microbial; D004405:Dysentery, Bacillary / Q000453:epidemiology / Q000382:microbiology*; D004587:Electrophoresis, Agar Gel; D005002:Ethiopia / Q000453:epidemiology; D006801:Humans; D008970:Molecular Weight; D010957:Plasmids; D011815:R Factors; D012703:Serotyping; D012763:Shigella flexneri / Q000145:classification* / Q000187:drug effects / Q000235:genetics
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial