Identification and characterization of genes involved in excision of the Lactococcus lactis conjugative transposon Tn5276.

AUTOR(ES)

Rauch, P J

RESUMO

The 70-kb transposon Tn5276, originally detected in Lactococcus lactis NIZO R5 and carrying the genes for nisin production and sucrose fermentation, can be conjugally transferred to other L. lactis strains. Sequence analysis and complementation studies showed that the right end of Tn5276 contains two genes, designated xis and int, which are involved in excision. The 379-amino-acid int gene product shows high (up to 50%) similarity with various integrases, including that of the Tn916-related conjugative transposons. The xis gene product, like almost all known excisionase (Xis) proteins, is a small (68-residue), basic protein. Expression of both the Tn5276 int and xis genes is required for efficient excision of the ends of Tn5276 in Escherichia coli that appeared to be circularized in the excision process. Mutational analysis of the xis and int genes showed that excision efficiency is dependent on the integrity of the int gene but that an intact xis gene is also required for efficient excision.

Documentos Relacionados

• Characterization of the novel nisin-sucrose conjugative transposon Tn5276 and its insertion in Lactococcus lactis.
• Excision of the Conjugative Transposon Tn916 in Lactococcus lactis
• Molecular characterization of two proteins involved in the excision of the conjugative transposon Tn1545: homologies with other site-specific recombinases.
• Insertion of Transposon Tn917 Derivatives into the Lactococcus lactis subsp. lactis Chromosome
• Excision of a conjugative transposon in vitro by the Int and Xis proteins of Tn916.