Transposition of a gene encoding OXA-2 beta-lactamase.

A bla gene encoding OXA-2 beta-lactamase has been transposed from the Salmonella typhimurium R plasmid R1767. This transposable element which was designated Tn2410 encoded sulphonamide and mercury resistance in addition to the bla gene. It had a size of 18.5 kb and appeared to be flanked by small inverted repeats. Restriction enzyme analysis resulted in a detailed map of Tn2410, which showed a high degree of similarity with the published map of Tn2603, a transposon encoding OXA-1 beta-lactamase. The ampicillin and sulphonamide resistance genes on Tn2410 were mapped in a cluster on the region between the centre and the righ end of the map.