Listeria virulence factors

Invasion of mammalian cells: Internalin A and B. Escape from a single membrane vacuole: -LLO (a pore-forming cytotoxin), -PI-PLC (an enzyme that removes charged head groups from phospholipids). Cell-to cell spread: ActA - stimulate actin polymerisation, propels the bacterium, bacteria enter adjacent cells. Escape from double membrane vacuole: PC-PLC (PlcB) – a phospholipase that cleaves the head group from many different kinds of lipids. Regulation of virulence factors: PrfA – is a positive regulator of virulence genes, may respond to temperature