title: Expression of LAP, a SecA2-dependent secretory protein, is induced under anaerobic environment.
abstract: Listeria adhesion protein (LAP), an alcohol acetaldehyde dehydrogenase homolog (lmo1634) in Listeria monocytogenes, promotes bacterial adhesion to intestinal epithelial cells in vitro. Investigation of the effect of anaerobiosis, an intrinsic gastrointestinal condition, on LAP expression and LAP-mediated infection should elucidate its significance during intestinal infection. The influence of anaerobiosis on LAP expression was determined by growing L. monocytogenes wild type (WT), and lap-deficient (KB208) and -complemented (CKB208) strains anaerobically and monitoring LAP in secreted, cell wall, and whole-cell protein fractions. The effect of anaerobiosis on LAP-mediated infection was evaluated in cell culture adhesion assays and mouse infection models. Additionally, the role of secretory system SecA2 in LAP secretion was investigated. Anaerobic growth induced significant increases in level of lap transcript and protein secretion, and secretion was SecA2-dependent. Anaerobiosis facilitated greater LAP-mediated adhesion of L. monocytogenes to cultured intestinal cells. Oral administration of WT, KB208 and CKB208 to mice confirmed that LAP is essential for full virulence, and anaerobically-grown WT exhibited greater translocation to liver and spleen relative to aerobically-grown organisms. LAP, a SecA2-dependent secreted virulence factor, plays an important role during intestinal infection, particularly when L. monocytogenes is subjected to an anaerobic environment.
authors.affiliation: Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, Indiana 47907, USA.
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Burkholder
authors.forename: Kwang-Pyo
authors.initials: KP
authors.lastname: Kim
authors.forename: Krishna K
authors.initials: KK
authors.lastname: Mishra
authors.forename: Sarimar
authors.initials: S
authors.lastname: Medina
authors.forename: Byoung-Kwon
authors.initials: BK
authors.lastname: Hahm
authors.forename: Hyochin
authors.initials: H
authors.lastname: Kim
authors.forename: Arun K
authors.initials: AK
authors.lastname: Bhunia
mesh_terms: D018829:Adhesins, Bacterial / Q000096:biosynthesis*; D000693:Anaerobiosis; D000818:Animals; D001422:Bacterial Adhesion; D002460:Cell Line; D002473:Cell Wall / Q000737:chemistry; D003470:Culture Media / Q000737:chemistry; D005260:Female; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D006801:Humans; D008089:Listeria monocytogenes / Q000737:chemistry / Q000502:physiology*; D008088:Listeriosis / Q000382:microbiology; D008099:Liver / Q000382:microbiology; D051379:Mice; D008805:Mice, Inbred A; D013154:Spleen / Q000382:microbiology; D014774:Virulence
chemical_list: D018829:Adhesins, Bacterial; D003470:Culture Media