Purification and characterization of a C5a-inactivating enzyme from human peritoneal fluid.
Earlier work has suggested that familial Mediterranean fever, an inherited disorder characterized by sporadic episodes of inflammation involving the pleural and peritoneal cavities and the joints, is caused by the lack of a C5a inactivator normally found in serosal fluid. We have purified this inactivator from ascites fluid and obtained a protein of molecular weight 53 to 56 kD with a specific activity 10,000-fold greater than the crude material. On Western blot, an inhibitory antibody recognized a single antigenic species at the same molecular weight. The enzyme had no activity against denatured bovine serum albumin. With recombinant C5a as substrate, the Km and Vm were 3.4 mumol/L and 52 nmol C5a/min/mg protein, respectively.
Ayesh
S K
SK
Hematology Unit, Hadassah University Hospital, Mount Scopus, Jerusalem, Israel.
Azar
Y
Y
Barghouti
I I
II
Ruedi
J M
JM
Babior
B M
BM
Matzner
Y
Y
D001202:Ascitic Fluid / Q000201:enzymology*; D002633:Chemotaxis; D015936:Complement C5a / Q000037:antagonists & inhibitors; D006801:Humans; D012697:Serine Endopeptidases / Q000302:isolation & purification*
C041833:complement C5a-inhibitors; D015936:Complement C5a; D012697:Serine Endopeptidases