title: Bioinformatics identification of MurJ (MviN) as the peptidoglycan lipid II flippase in Escherichia coli.
abstract: Peptidoglycan is a cell-wall glycopeptide polymer that protects bacteria from osmotic lysis. Whereas in gram-positive bacteria it also serves as scaffold for many virulence factors, in gram-negative bacteria, peptidoglycan is an anchor for the outer membrane. For years, we have known the enzymes required for the biosynthesis of peptidoglycan; what was missing was the flippase that translocates the lipid-anchored precursors across the cytoplasmic membrane before their polymerization into mature peptidoglycan. Using a reductionist bioinformatics approach, I have identified the essential inner-membrane protein MviN (renamed MurJ) as a likely candidate for the peptidoglycan flippase in Escherichia coli. Here, I present genetic and biochemical data that confirm the requirement of MurJ for peptidoglycan biosynthesis and that are in agreement with a role of MurJ as a flippase. Because of its essential nature, MurJ could serve as a target in the continuing search for antimicrobial compounds.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA. nruiz@princeton.edu
authors.forename: Natividad
authors.initials: N
authors.lastname: Ruiz
mesh_terms: D019295:Computational Biology; D004926:Escherichia coli / Q000201:enzymology* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D010457:Peptidoglycan / Q000096:biosynthesis*; D049294:Phospholipid Transfer Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D010457:Peptidoglycan; D049294:Phospholipid Transfer Proteins