Demonstration of endogenous inhibitors for the formation of 14,15-oxido-5,8,11-eicosatrienoic acid from phosphatidylinositol in bovine lung extract.
Bovine lung extract contained an enzyme or enzyme system that catalyzed the formation of 14,15-oxido-5,8,11-eicosatrienoic acid from phosphatidylinositol. The enzyme activity increased markedly during the course of purification, apparently due to the removal of two endogenous inhibitors from the enzyme. Using membranes with known molecular weight cut-offs, we estimated the Mr of Inhibitor 1 to be between 10,000 and 100,000 and Inhibitor 2 less than 1,000. Inhibitor 1 appeared to be partially inactivated by trypsin and was heat labile, whereas Inhibitor 2 was resistant to trypsin and was heat resistant. Both inhibitors were hydrophilic.
Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, TN 38101.
Z L
ZL
Xiao
C
C
Moreno
L R
LR
Ballou
W Y
WY
Cheung
D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D004851:Epoxide Hydrolases / Q000037:antagonists & inhibitors; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D006358:Hot Temperature; D008168:Lung / Q000378:metabolism*; D008970:Molecular Weight; D010716:Phosphatidylinositols / Q000378:metabolism*; D010741:Phospholipases A / Q000037:antagonists & inhibitors
D005231:Fatty Acids, Unsaturated; D010716:Phosphatidylinositols; C046782:14,15-epoxy-5,8,11-eicosatrienoic acid; D010741:Phospholipases A; D004851:Epoxide Hydrolases; D015126:8,11,14-Eicosatrienoic Acid