Listeria monocytogenes listeriolysin O and phosphatidylinositol-specific phospholipase C affect adherence to epithelial cells.
Listeria monocytogenes, a foodborn intracellular animal and human pathogen, produces several exotoxins contributing to virulence. Among these are listeriolysin O (LLO), a pore-forming cholesterol-dependent hemolysin, and a phosphatidylinositol-specific phospholipase C (PI-PLC). LLO is known to play an important role in the escape of bacteria from the primary phagocytic vacuole of macrophages, and PI-PLC supports this process. Evidence is accumulating that LLO and PI-PLC are multifunctional virulence factors with many important roles in the host-parasite interaction other than phagosomal membrane disruption. LLO and PI-PLC may induce a number of host cell responses by modulating signal transduction of infected cells via intracellular Ca2+ levels and the metabolism of phospholipids. This would result in the activation of host phospholipase C and protein kinase C. In the present study, using Bacillus sub tilis strains expressing LLO, PI-PLC, and simultaneously LLO and PI-PLC, we show that LLO and PI-PLC enhance bacterial binding to epithelial cells Int407, with LLO being necessary and PI-PLC playing an accessory role. The results of this work suggest that these two listerial proteins act on epithelial cells prior to internalization.
Krawczyk-Balska
Agata
A
Department of General Microbiology, Institute of Microbiology, University of Warsaw, Poland. akra@biol.uw.edu.pl
Bielecki
Jacek
J
D000818:Animals; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D001422:Bacterial Adhesion; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004847:Epithelial Cells / Q000382:microbiology*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006460:Hemolysin Proteins; D006461:Hemolysis; D006801:Humans; D007422:Intestines / Q000166:cytology / Q000382:microbiology; D008089:Listeria monocytogenes / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity*; D043265:Phosphatidylinositol Diacylglycerol-Lyase / Q000235:genetics / Q000378:metabolism*; D054801:Phosphoinositide Phospholipase C
D001427:Bacterial Toxins; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase; C038705:hlyA protein, Listeria monocytogenes