Association of the strA-strB genes with plasmids and transposons in the present-day bacteria and in bacterial strains from permafrost

Molecular structure and translocation of a multiple antibiotic resistance region of aPsychrobacter psychrophiluspermafrost strain

“…We found that about 30% of the isolated strains had been simultaneously resistant to two and more antibiotics of different classes (Mindlin et al , 2008). Furthermore, we demonstrated that in some environmental streptomycin‐resistant strains, the strA‐strB genes were associated with mobile elements such as plasmids and transposons (Petrova et al , 2008). We have also described a strain of Psychrobacter psychrophilus MR29‐12 isolated from a permafrost sample collected at the coast of the Eastern‐Siberian Sea (Mindlin et al , 2008), which carried an R plasmid pKLH80 specifying resistance to streptomycin and tetracycline.…”

“…We have also described a strain of Psychrobacter psychrophilus MR29‐12 isolated from a permafrost sample collected at the coast of the Eastern‐Siberian Sea (Mindlin et al , 2008), which carried an R plasmid pKLH80 specifying resistance to streptomycin and tetracycline. Although both determinants could be mobilized in mating‐out assays (Petrova et al , 2008), their association with transposable elements remained to be clarified. This study was undertaken to examine the molecular structure of the antibiotic resistance genes from the permafrost strain of P. psychrophilus MR29‐12 and the structure of the putative mobile element associated with these genes.…”

ISPpy1, a novel mobile element of the ancient Psychrobacter maritimus permafrost strain: Translocations in Escherichia coli K-12 cells and formation of composite transposons

“…Con sidering this circumstance, we attempted to study the origin and evolution of antibiotic resistance determi nants and mechanisms of their distribution in analysis of ancient bacterial strains preserved in permafrost sediments, that is, existing long before the antibiotic era. This approach yielded positive results: we suc ceeded for the first time to isolate from permafrost sediments the different bacterial strains resistant to antibiotics, including multidrug resistant bacteria [7][8][9]. We showed that determinants of antibiotic resis tance in ancient strains are highly homologous to those of present day clinical strains [7][8][9][10].…”

“…This approach yielded positive results: we suc ceeded for the first time to isolate from permafrost sediments the different bacterial strains resistant to antibiotics, including multidrug resistant bacteria [7][8][9]. We showed that determinants of antibiotic resis tance in ancient strains are highly homologous to those of present day clinical strains [7][8][9][10]. In addi tion, mobile elements (plasmids, transposons, and integrons with cassette genes) responsible for the dis tribution of resistance determinants in ancient strains and mobile elements related to those of contemporary bacteria were detected [9][10][11].…”

Transposon Tn5393e Carrying theaphA1-Containing Transposon Tn6023Upstream ofstrABDoes Not Confer Resistance to Streptomycin

“…This form of the transposon has been detected in bacteria recovered from permafrost, indicating that it is an ancient structure. 11 In Tn5393, the strAB genes have been shown to be cotranscribed from the tnpR promoter 16 and expressed using a ribosome binding site upstream of strA and translational coupling for strB. Expression was increased in the variant form that carries the IS1133 possibly because of a stronger promoter in the IS.…”