Transposition of the oxacillin-hydrolyzing penicillinase gene

Abstract

We have found that the oxacillin-hydrolyzing penicillinase gene (oxa) encoded by plasmid RGN238 transposes to various plasmids in a recA background. We call this transposable element Tn2603. Tn2603 encodes the genes for streptomycin, sulfonamide, and mercury resistance in addition to the oxa gene. Tn2603 has a molecular size of 19.6 kilobase pairs and appears to be flanked by small inverted repeat sequences of about 200 base pairs long.

A gene and its product required for transposition of resistance transposon Tn2603

“…Construction of deletions in pMK1::Tn2603 plasmids. pMK1::Tn2603-1 is a derivative of plasmid pMK1 with Tn2603 inserted in the ColEl plasmid region and has a molecular size of 33 kb (19). A restriction cleavage map of the plasmid has been constructed with various restriction endonucleases (Fig.…”

“…Strains WA5023 and X2207 were kindly provided by M. Yoshikawa and M. Inoue, respectively. The plasmids pMK1: :Tn2603-1, pMB9::Tn2603-1, R386, and pACYC184 were previously described (18,19). pMK1::Tn2603-11 is a plasmid with Tn2603 from R388::Tn2603-1 inserted into pMK1 (19).…”

“…The plasmids pMK1: :Tn2603-1, pMB9::Tn2603-1, R386, and pACYC184 were previously described (18,19). pMK1::Tn2603-11 is a plasmid with Tn2603 from R388::Tn2603-1 inserted into pMK1 (19). pMK1 is a variant of plasmid ColEl, contains TnS, and has a molecular size of 12 kb.…”

“…Determination of Tn2603-promoted nmsposition by a conjugal mating assay. Determination of transposition frequency was carried out essentially by the method described before (19), except that WA5023 Rifr was used instead of P3478 Riff as the recipient bacterium.…”

“…Tn2603 is 20 kilobases (kb) in length and encodes multiple resistance to ampicillin, streptomycin, sulfonamide, and mercury (19). Ampicillin resistance of Tn2603 is due to production of a type II ,B-lactamase (alternatively, oxacillinhydrolyzing 3-lactamase, designated OXA-1 [17]).…”