title: The cell wall subproteome of Listeria monocytogenes.
abstract: The surface subproteome of Listeria monocytogenes that includes many proteins already known to be involved in virulence and interaction with host cells has been characterized. A new method for the isolation of a defined surface proteome of low complexity has been established based on serial extraction of proteins by different salts at high concentration, and in all 55 proteins were identified by N-terminal sequencing and mass spectrometry. About 16% of these proteins are of unknown function and three proteins have no orthologue in the nonpathogenic L. innocua and might be involved in virulence mechanisms. Remarkably, a relatively high number of proteins with a function in the cytoplasmic compartment was identified in this surface proteome. These proteins had neither predicted or detectable signal peptides nor could any modification be observed except removal of the N-terminal methionine. Enolase (Lmo2455) is one of these proteins. It was shown to be present in the cell wall of the pathogen by immunoelectron microscopy and, along with heat shock factor DnaK (Lmo1473), elongation factor TU (Lmo2653), and glyceraldehyde-3-phosphate dehydrogenase (Lmo2459), it was found to be able to bind human plasminogen in overlay blots and surface plasmon resonance (SPR) experiments. The KD values of these interactions were determined by SPR measurements. The data indicate a possible role of these proteins as receptors for human plasminogen on the bacterial cell surface. The potential role of this recruitment of a host protease for extracellular invasion mechanisms is discussed.
authors.affiliation: Department of Cell Biology, German Research Centre for Biotechnology (GBF), Braunschweig, Germany.
authors.forename: Jessica
authors.initials: J
authors.lastname: Schaumburg
authors.forename: Oliver
authors.initials: O
authors.lastname: Diekmann
authors.forename: Petra
authors.initials: P
authors.lastname: Hagendorff
authors.forename: Simone
authors.initials: S
authors.lastname: Bergmann
authors.forename: Manfred
authors.initials: M
authors.lastname: Rohde
authors.forename: Sven
authors.initials: S
authors.lastname: Hammerschmidt
authors.forename: Lothar
authors.initials: L
authors.lastname: Jänsch
authors.forename: Jürgen
authors.initials: J
authors.lastname: Wehland
authors.forename: Uwe
authors.initials: U
authors.lastname: Kärst
mesh_terms: D000626:Aminopeptidases / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry*; D015153:Blotting, Western; D002473:Cell Wall / Q000378:metabolism*; D003001:Cloning, Molecular; D019295:Computational Biology; D003593:Cytoplasm / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008024:Ligands; D008089:Listeria monocytogenes / Q000378:metabolism*; D013058:Mass Spectrometry; D008715:Methionine / Q000737:chemistry; D016253:Microscopy, Immunoelectron; D010958:Plasminogen / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry; D020543:Proteome; D012492:Salts / Q000494:pharmacology; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D020349:Surface Plasmon Resonance; D013997:Time Factors; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D008024:Ligands; D011506:Proteins; D020543:Proteome; D012492:Salts; D010958:Plasminogen; D008715:Methionine; D000626:Aminopeptidases; C072222:aminopeptidase C