ATP-dependent leader peptide cleavage by NukT, a bifunctional ABC transporter, during lantibiotic biosynthesis.

摘要: NukT, a possible ABC transporter maturation and secretion (AMS) protein, may contribute to the cleavage of leader peptide NukA, which is prepeptide lantibiotic nukacin ISK-1, ISK-1 transport. In this study, we reconstituted in vitro peptidase activity full-length NukT overexpressed inside-out membrane vesicles Staphylococcus carnosus TM300. We found that presence unusual amino acids NukA required for cleavage. Furthermore, was inhibited by phenylmethylsulfonyl fluoride, serine/cysteine protease inhibitor; finding strongly suggests like other AMS proteins, cysteine protease. Interestingly, depended on ATP hydrolysis. These results suggest N-terminal domain cooperatively function with C-terminal ATP-binding domain. This first study lantibiotics reports processing mechanism bifunctional transporter.