Genetic stability and worldwide dissemination of integron insert encoding trimethoprim resistance.
A hospital-based surveillance study of class 1 integron-positive Acinetobacter isolates in the Urals and Siberia (Russia) demonstrated that dihydrofolate reductase gene (dfrA5) was located in a functional gene cassette insertion driven from a promoter of a weak type. This insertion is an example of the integron-associated trimethoprim resistance disseminated worldwide from the free-living animals to human. Despite the long-term persistence as an integron insert any loss or modifications in the nucleotide sequence especially at attC site was not observed. Nucleotide sequence previously referred as a weak type promoter may be considered as a wild-type configuration of an integron promoter region.
Solomennyi
Aleksandr
A
Laboratory of Aquatic Microbiology, Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, Perm, Russian Federation. solomen@iegm.ru
Saralov
Aleksandr
A
D000150:Acinetobacter / Q000235:genetics* / Q000302:isolation & purification; D040981:Acinetobacter baumannii / Q000235:genetics; D001483:Base Sequence; D005798:Genes, Bacterial; D006801:Humans; D032023:Integrons / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D012426:Russia / Q000453:epidemiology; D012800:Siberia / Q000453:epidemiology; D014296:Trimethoprim Resistance / Q000235:genetics*