Abstract
Seven (6.1%) of 115 strains of Salmonella typhi isolated from Malaysian patients harbored a single large plasmid of 71 to 166mD. Two of the seven plasmidbearing strains were resistant to chloramphenicol (Cm) and tetracycline (Tc) and they transferred Cm and Tc resistance traits to Escherichia coli K12 at frequencies from 1.6×10-7 to 1.9×10-6. Agarose gel electrophoresis provided evidence that the resistance traits were cotransferred on a conjugative plasmid. The significance and importance of these results are discussed.
