title: Requirement of lipid II biosynthesis for cell division in cell wall-less Wolbachia, endobacteria of arthropods and filarial nematodes.
abstract: Obligate Wolbachia endobacteria have a reduced genome and retained genes are hypothesized to be crucial for survival. Although intracellular bacteria do not need a stress-bearing peptidoglycan cell wall, Wolbachia encode proteins necessary to synthesize the peptidoglycan precursor lipid II. The activity of the enzymes catalyzing the last two steps of this pathway was previously shown, and Wolbachia are sensitive to inhibition of lipid II synthesis. A puzzling characteristic of Wolbachia is the lack of genes for l-amino acid racemases essential for lipid II synthesis. Transcription analysis showed the expression of a possible alternative racemase metC, and recombinant Wolbachia MetC indeed had racemase activity that may substitute for the absent l-Ala racemase. However, enzymes needed to form mature peptidoglycan are absent and the function of Wolbachia lipid II is unknown. Inhibition of lipid II biosynthesis resulted in enlargement of Wolbachia cells and redistribution of Wolbachia peptidoglycan-associated lipoprotein, demonstrating that lipid II is required for coordinated cell division and may interact with the lipoprotein. We conclude that lipid II is essential for Wolbachia cell division and that this function is potentially conserved in the Gram-negative bacteria.
authors.affiliation: Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Vollmer
authors.forename: Andrea
authors.initials: A
authors.lastname: Schiefer
authors.forename: Tanja
authors.initials: T
authors.lastname: Schneider
authors.forename: Karen
authors.initials: K
authors.lastname: Jülicher
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Johnston
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Taylor
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Sahl
authors.forename: Achim
authors.initials: A
authors.lastname: Hoerauf
authors.forename: Kenneth
authors.initials: K
authors.lastname: Pfarr
mesh_terms: D000818:Animals; D001181:Arthropods / Q000382:microbiology; D053898:Biosynthetic Pathways / Q000235:genetics; D002455:Cell Division; D002473:Cell Wall / Q000378:metabolism*; D020869:Gene Expression Profiling; D009348:Nematoda / Q000382:microbiology; D010457:Peptidoglycan / Q000096:biosynthesis; D014538:Uridine Diphosphate N-Acetylmuramic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D020577:Wolbachia / Q000502:physiology*
chemical_list: D010457:Peptidoglycan; D014538:Uridine Diphosphate N-Acetylmuramic Acid; C069249:muramyl-NAc-(pentapeptide)pyrophosphoryl-undecaprenol