The Lengths of attI Sites Have No Effect on the Transcription and Expression of the Cassette and Integrase Genes

摘要

Class 1 integron is a genetic element with the ability to capture and express of the exogenous drug-resistance genes embedded in gene cassettes, offering bacteria with multi-drug resistance. The structures of the integron itself can regulate the transcription and express levels of the cassette genes. In this study, the effects of the attI sites on the transcription and express of the cassette and integrase genes were reported. pACYC184 plasmids, containing cloned integron fragments which differed only with respect to the lengths of attI sites were transferred into E. coli JM109. Then, the transcription and expression levels of the integrase and the first cassette gene after Pc promoter were detected in the corresponding recombinant strains. The results showed that the lengths of attI sites had no effect on the transcription and expression of the gene cassettes and integrase genes. This research was reported for the first time.