Catalytic and non-catalytic functions of human IIA phospholipase A2.
Group IIA phospholipase A2 (PLA2) is a low-molecular-mass secreted PLA2 enzyme that has been identified as an acute phase protein with a role in the inflammatory response to infection and trauma. The protein is possibly unique in being highly cationic and having a global distribution of surface arginine and lysine residues. This structure supports two functions of the protein. (1) An anti-bacterial role where the enzyme is targeted to the anionic cell membrane of Gram-positive bacteria and phospholipid hydrolysis assists in bacterial killing. (2) A proposed non-catalytic role in which the protein forms supramolecular aggregates with anionic phospholipid vesicles or debris. These aggregates are then internalized via interactions with cell surface heparin sulphate proteoglycans and macropinocytosis for disposal by macrophages.
Birts
Charles N
CN
School of Biological Sciences, University of Southampton, Boldrewood Campus, Southampton, United Kingdom.
Barton
C Howard
CH
Wilton
David C
DC
D000209:Acute-Phase Proteins / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000378:metabolism; D054501:Group II Phospholipases A2 / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000378:metabolism
D000209:Acute-Phase Proteins; D000900:Anti-Bacterial Agents; D054501:Group II Phospholipases A2; C516287:PLA2G2A protein, human