Polymyxin B nonapeptide (TFA)

Polymyxin B nonapeptide TFA is a cyclic peptide obtained from Polymyxin B by proteolytic removal of its terminal amino acyl residue. Polymyxin B nonapeptide TFA is less toxic, lacks bactericidal activity, and retains its ability to render gram-negative bacteria susceptible to several antibiotics by permeabilizing their outer membranes[1][2][3].

FC(F)(F)C(O)=O.FC(F)(F)C(O)=O.FC(F)(F)C(O)=O.FC(F)(F)C(O)=O.O=C(N[C@H](C(N[C@H](C(N[C@H](C(N[C@@]1([H])[C@H](O)C)=O)CCN)=O)CCN)=O)CC(C)C)[C@H](NC([C@@H](NC([C@H](CCNC1=O)NC([C@H](CCN)NC([C@@H](N)[C@H](O)C)=O)=O)=O)CCN)=O)CC2=CC=CC=C2.FC(F)(F)C(O)=O

[1]Al-Marzooq F, et al. Discerning the role of polymyxin B nonapeptide in restoring the antibacterial activity of azithromycin against antibiotic-resistant Escherichia coli. Front Microbiol. 2022 Sep 21;13:998671.|[2]Danner RL,et al. Purification, toxicity, and antiendotoxin activity of polymyxin B nonapeptide. Antimicrob Agents Chemother. 1989 Sep;33(9):1428-34.|[3]Ofek I, et al. Antibacterial synergism of polymyxin B nonapeptide and hydrophobic antibiotics in experimental gram-negative infections in mice. Antimicrob Agents Chemother. 1994 Feb;38(2):374-7.