Analyses of traA, int-Tn, and xis-Tn mutations in the conjugative transposon Tn916 in Enterococcus faecalis.

The conjugative transposon Tn916 moves intercellularly via an excision/insertion mechanism that involves products of int-Tn and xis-Tn. Tn5-insertion mutations in these genes were found to be complemented in an Enterococcus faecalis host by specific coresident transposons harboring the corresponding wild-type allele. A determinant designated traA, partially overlapping and divergently transcribed from xis-Tn, is thought to encode a key positively acting regulatory protein needed for expression of conjugation functions. This locus was also shown to express a trans-acting product.