Determination of Transposition Property of Neomycin , Streptomycin and Trimethprim Resistance Genes in Clinical Isolates of Escherichia coli and Proteus mirabilis


Twenty bacterial isolates were collected from human diarrheal samples and then identified. Seven out of twenty isolates were E. coli and three P. mirabilis . These isolates were checked for their resistance to six antibiotics and two heavy metals ( HgCl2 and Cdcl2). The bacterial isolates showed variation in their resistance to antibiotics and heavy metals.and only one E. coli but all P. mirabilis isolates showed high level of resistance. Transposition induction of genes in the two chosen bacterial isolates was carried out.. Our results suggested that in E. coli isolate, neomycin resistance gene was induced to jump and insert itself into chloramphenicol and tetracyclin resistance genes causing them to mutate .in percents reaching 80% and 8% respectively. On the other hand, the streptomycin resistance gene transposition appear to be specific for generating mutations in the heavy metals resistance genes at rates 48% and 100 % respectively. In addition, transposition induction of the above genes in the chosen P. mirbilis isolate seemed to cause mutations in ampicilin, chloramphenicol and tetracyclin resistance genes ranging between 2 and 4 % .