Knerr, Patrick J.Oman, Trent J.Garcia De Gonzalo, Chantal V.van der Donk, Wilfred A.Lupoli, Tania J.Kahne, Suzanne2013-05-172012Knerr, Patrick J., Trent J. Oman, Chantal V. Garcia De Gonzalo, Tania J. Lupoli, Suzanne Walker, and Wilfred A. van der Donk. 2012. Non-proteinogenic amino acids in lacticin 481 analogues result in more potent inhibition of peptidoglycan transglycosylation. ACS Chemical Biology 7(11): 1791-1795.1554-89291554-8937http://nrs.harvard.edu/urn-3:HUL.InstRepos:10646332Lantibiotics are ribosomally synthesized and post-translationally modified peptide natural products that contain the thioether structures lanthionine and methyllanthionine and exert potent antimicrobial activity against Gram-positive bacteria. At present, detailed modes-of-action are only known for a small subset of family members. Lacticin 481, a tricyclic lantibiotic, contains a lipid II binding motif present in related compounds such as mersacidin and nukacin ISK-1. Here, we show that lacticin 481 inhibits PBP1b-catalyzed peptidoglycan formation. Furthermore, we show that changes in potency of analogues of lacticin 481 containing non-proteinogenic amino acids correlate positively with the potency of inhibition of the transglycosylase activity of PBP1b. Thus, lipid II is the likely target of lacticin 481, and use of non-proteinogenic amino acids resulted in stronger inhibition of the target. Additionally, we demonstrate that lacticin 481 does not form pores in the membranes of susceptible bacteria, a common mode-of-action of other lantibiotics.en-USJournal Article2013-05-1710.1021/cb300372b