IS 1675 , a Novel Lactococcal Insertion Element, Forms a Transposon-Like Structure Including the Lacticin 481 Lantibiotic Operon
Résumé
ABSTRACT Two copies of IS 1675 , a novel lactococcal insertion element from the IS 4 family, are present on a 70-kb plasmid, where they frame the lantibiotic lacticin 481 operon. The whole structure could be a composite transposon designated Tn 5721 . This study shows that the lacticin 481 operon does not include any regulatory gene and provides a new example of a transposon-associated bacteriocin determinant. We identified five other IS 1675 copies not associated with the lacticin 481 operon. The conservation of IS 1675 flanking sequences suggested a 24-bp target site.