Food Biochemistry and Food Processing

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O-antigen

Lipopolysaccharide

(nonprotein)

LPS may be directly related to the

(LPS)

upregulation of the Gb3 receptor or indirectly related through the upregulation of tumor necrosis factor 1 and other preinflammatory cytokines (Currie et al. 2001, Lingwood et al. 1998, Tesh 1998).

L. monocytogenes

Listeriolysin

Thiol activated

58 kDa

Pore-forming protein binds to cholesterol

O (LLO)

cytolysin

in the host membrane. The protein then oligomerizes, forms a pore, and allows the escape of

L. monocytogenes

from the

phagosome of the host into the cytoplasm where it can replicate.

Phospholipase

Phospholipase C

33 kDa

Hydrolyses phosphotidylinositol—plays an

C-A (PLC-A)

overlapping role with PLC-B in degrading the phagosome membrane or vacuole, so the bacteria can escape to the cytosol or spread from cell to cell (Bannam and Goldfine 1998, Titball 1999).

Phospholipase

Phospholipase C

30 kDa

Broad range phospholipase—plays an

C-B (PLC-B)

overlapping role with PLC-A in degrading the phagosome membrane or vacuole, so the bacteria can escape to thecytosol or spread from cell to cell(Snyder and Marquis 2003, Titball 1999).

P60 protein

Extracellular

60 kDa

Extracellular protein associated with the

(Iap)

protein

invasion of phagocytic cells. The protein has also been implicated in cell division (Cabanes et al. 2002, Klein and Juneja 1997).

S. aureus

Enterotoxins

Enterotoxins

22–27 kDa

This group includes haemolysins, nucleases,

A-E and G-J

proteases, leucocidins, collagenases, cell-surface proteins and superantigens, allowing the bacteria to colonize and persist in host organisms (Melton-Celsa and O’Brien 1998).

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