title: DivIVA affects secretion of virulence-related autolysins in Listeria monocytogenes.
abstract: DivIVA is a well-conserved coiled-coil protein present in most Gram-positive bacteria and has been implicated in division site selection, peptidoglycan biosynthesis and sporulation. DivIVA proteins bind lipid membranes and characteristically accumulate at curved membrane areas, i.e. the cell poles and the division site, to which they recruit various interaction partners. We have studied the role of this morphogen in the human pathogen Listeria monocytogenes and our results suggest a novel mechanism by which DivIVA contributes to cell division. Contrary to expectation a ΔdivIVA mutant exhibited a pronounced chaining phenotype rather than a defect in cell division which we attributed to reduced extracellular levels of the autolytic enzymes p60 and MurA. We demonstrate that this is due to a malfunction in secretion of these autolysins and phenotypic comparison of the ΔdivIVA strain with a ΔsecA2 mutant suggests that DivIVA influences the activity of the SecA2 secretion route in L. monocytogenes. Also from the phenotypic analysis it was clear that divIVA affected swarming motility, biofilm formation, invasiveness and cell-to-cell spread in cell culture infection models. Thus, our experiments show that DivIVA is an important factor for various listerial traits that are essential for the pathogenicity of this organism.
authors.affiliation: Robert Koch Institute, FG11 - Division of Bacterial Infections, Burgstrasse 37, 38855 Wernigerode, Germany. halbedels@rki.de
authors.forename: Sven
authors.initials: S
authors.lastname: Halbedel
authors.forename: Birgit
authors.initials: B
authors.lastname: Hahn
authors.forename: Richard A
authors.initials: RA
authors.lastname: Daniel
authors.forename: Antje
authors.initials: A
authors.lastname: Flieger
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development; D018797:Cell Cycle Proteins / Q000172:deficiency / Q000378:metabolism*; D017353:Gene Deletion; D006801:Humans; D008089:Listeria monocytogenes / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D008124:Locomotion; D008969:Molecular Sequence Data; D009238:N-Acetylmuramoyl-L-alanine Amidase / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: C078516:60 kDa protein, Listeria monocytogenes; D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; C104636:DivIVA protein, bacteria; D037521:Virulence Factors; D019883:Alkyl and Aryl Transferases; C022566:UDP-N-acetylglucosamine 1-carboxyvinyltransferase; D009238:N-Acetylmuramoyl-L-alanine Amidase