Premium
Characterization of cockroach ( Periplaneta americana ) fat body phospholipase A 2 activity
Author(s) -
Sun D.,
Steele J.E.
Publication year - 2002
Publication title -
archives of insect biochemistry and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.576
H-Index - 66
eISSN - 1520-6327
pISSN - 0739-4462
DOI - 10.1002/arch.10014
Subject(s) - periplaneta , american cockroach , cockroach , biology , phospholipase , cytosol , phospholipase a , enzyme , biochemistry , substrate (aquarium) , centrifugation , phospholipase c , chromatography , phospholipase a2 , chemistry , ecology
A phospholipase has been identified in the fat body of the American cockroach, Periplaneta americana , which removes fatty acid from the sn ‐2 acyl position of an artificial substrate. The enzyme has been characterized using a crude preparation obtained by low‐speed centrifugation of the homogenized tissue. With 1‐hexadecanoyl‐2‐(1‐pyrenedecanoyl)‐ sn ‐glycero‐3‐phosphocholine as the substrate, the K m has been estimated to be 1.17 μM and the v max 113.5 pmol/min/mg protein. The phospholipase has a pH optimum close to 7 and shows maximal activity at 50°C. Activity of the phospholipase has been determined in cytosolic and plasma membrane fractions. The specific activity of the latter fraction is approximately twice that of the cytosol. The enzyme in both fractions is Ca 2+ ‐independent. Arch. Insect Biochem. Physiol. 49:149–157, 2002. © 2002 Wiley‐Liss, Inc.