title: Biochemical characterization of soluble phospholipase A2 from rheumatoid synovial fluid.
abstract: Radiolabeled E. coli, Phosphatidylethanolamine (PE) and Phosphatidylcholine (PC), were used to characterize the phospholipase A2 (PLA2) activity in synovial fluid (SF) from rheumatoid arthritis (RA) patients. Cell-free fractions of SF contain a PLA2 enzyme that preferentially releases [14C]oleic acid from E. coli, requires calcium and is optimally active at neutral pH. Purified PE, but not PC is also readily degraded by the soluble enzyme. A cell-associated PLA2 present in sonicates of SF mononuclear cells and neutrophils preferentially releases [3H]AA from E. coli. These studies suggest the presence of at least two different enzymes with activity of PLA2 in rheumatoid SF.
authors.affiliation: Department of Medicine, Section on Rheumatology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27103.
authors.forename: H
authors.initials: H
authors.lastname: Gonzalez-Buritica
authors.forename: D M
authors.initials: DM
authors.lastname: Smith
authors.forename: R A
authors.initials: RA
authors.lastname: Turner
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001172:Arthritis, Rheumatoid / Q000201:enzymology*; D002118:Calcium / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004926:Escherichia coli / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010740:Phospholipases / Q000378:metabolism*; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2; D010743:Phospholipids / Q000378:metabolism; D013379:Substrate Specificity; D013582:Synovial Fluid / Q000201:enzymology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D008823:Micelles; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D004492:Edetic Acid; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2; D002118:Calcium