title: The lantibiotic NAI-107 binds to bactoprenol-bound cell wall precursors and impairs membrane functions.
abstract: The lantibiotic NAI-107 is active against Gram-positive bacteria including vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. To identify the molecular basis of its potency, we studied the mode of action in a series of whole cell and in vitro assays and analyzed structural features by nuclear magnetic resonance (NMR). The lantibiotic efficiently interfered with late stages of cell wall biosynthesis and induced accumulation of the soluble peptidoglycan precursor UDP-N-acetylmuramic acid-pentapeptide (UDP-MurNAc-pentapeptide) in the cytoplasm. Using membrane preparations and a complete cascade of purified, recombinant late stage peptidoglycan biosynthetic enzymes (MraY, MurG, FemX, PBP2) and their respective purified substrates, we showed that NAI-107 forms complexes with bactoprenol-pyrophosphate-coupled precursors of the bacterial cell wall. Titration experiments indicate that first a 1:1 stoichiometric complex occurs, which then transforms into a 2:1 (peptide: lipid II) complex, when excess peptide is added. Furthermore, lipid II and related molecules obviously could not serve as anchor molecules for the formation of defined and stable nisin-like pores, however, slow membrane depolarization was observed after NAI-107 treatment, which could contribute to killing of the bacterial cell.
authors.affiliation: Institute of Medical Microbiology, Immunology and Parasitology, Pharmaceutical Microbiology Section, University of Bonn, 53115 Bonn, Germany. Electronic address: dmuench@uni-bonn.de.
authors.forename: Daniela
authors.initials: D
authors.lastname: Münch
authors.affiliation: Institute of Medical Microbiology, Immunology and Parasitology, Pharmaceutical Microbiology Section, University of Bonn, 53115 Bonn, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Müller
authors.affiliation: Institute of Medical Microbiology, Immunology and Parasitology, Pharmaceutical Microbiology Section, University of Bonn, 53115 Bonn, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Schneider
authors.affiliation: Department of Biology of Microorganisms, Ruhr University Bochum, 44780 Bochum, Germany.
authors.forename: Bastian
authors.initials: B
authors.lastname: Kohl
authors.affiliation: Department of Biology of Microorganisms, Ruhr University Bochum, 44780 Bochum, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Wenzel
authors.affiliation: Department of Biology of Microorganisms, Ruhr University Bochum, 44780 Bochum, Germany.
authors.forename: Julia Elisabeth
authors.initials: JE
authors.lastname: Bandow
authors.affiliation: NAICONS, Srl, 20139 Milano, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Maffioli
authors.affiliation: NAICONS, Srl, 20139 Milano, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Sosio
authors.affiliation: NAICONS, Srl, 20139 Milano, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Donadio
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, 9000 Aalborg, Denmark.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Wimmer
authors.affiliation: Institute of Medical Microbiology, Immunology and Parasitology, Pharmaceutical Microbiology Section, University of Bonn, 53115 Bonn, Germany. Electronic address: hgsahl@uni-bonn.de.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Sahl
mesh_terms: D000595:Amino Acid Sequence; D001430:Bacteriocins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D004591:Electrophoresis, Polyacrylamide Gel; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D040901:Proteomics; D013211:Staphylococcus aureus / Q000187:drug effects; D013729:Terpenes / Q000378:metabolism*
chemical_list: D001430:Bacteriocins; D013729:Terpenes; C528150:microbisporicin; C000146:bactoprenol
keywords: Antibiotics; Cell Wall; Lantibiotics; Lipid II; Membrane; Nisin; Nuclear Magnetic Resonance; Peptidoglycan; Staphylococcus aureus; Teichoic Acid