TY - JOUR
T1 - Calcium-dependent oxidation of 5,8,11-icosatrienoic acid by the cyclooxygenase enzyme system
AU - Elliott, W. J.
AU - Morrison, A. R.
AU - Sprecher, H.
AU - Needleman, P.
PY - 1986
Y1 - 1986
N2 - Mead (5,8,11-icosatrienoic) acid was found to be metabolized by the cyclooxygenase enzyme system of ram seminal vesicle microsomes in a calcium-dependent manner. Although the enzyme converted Mead acid to products more slowly and less completely than the isomeric 8,11,14-icosatrienoic acid, both oxidations were inhibitable by indomethacin. Experiments using purified cyclooxygenase confirmed the participation of this enzyme system in the calcium-dependent oxidation. The products of the oxidation were separated by high performance liquid chromatography and analyzed by ultraviolet and gas chromatography-mass spectrometry. The spectra obtained were consistent with the products having the structures 13-hydroxy-5,8,11-icosatrienoate (the major product), 11-hydroxy-5,8,12-icosatrienoate, 9-hydroxy-5,7,11-icosatrienoate, and two isomeric 8,11-dihydroxy-5,9,12-icosatrienoates. No prostaglandin-like, cyclized products could be identified. This report is only the second to illustrate a calcium-dependent oxidation of a poly-unsaturated fatty acid by a cyclooxygenase enzyme system and further extends the metabolic potential of Mead acid.
AB - Mead (5,8,11-icosatrienoic) acid was found to be metabolized by the cyclooxygenase enzyme system of ram seminal vesicle microsomes in a calcium-dependent manner. Although the enzyme converted Mead acid to products more slowly and less completely than the isomeric 8,11,14-icosatrienoic acid, both oxidations were inhibitable by indomethacin. Experiments using purified cyclooxygenase confirmed the participation of this enzyme system in the calcium-dependent oxidation. The products of the oxidation were separated by high performance liquid chromatography and analyzed by ultraviolet and gas chromatography-mass spectrometry. The spectra obtained were consistent with the products having the structures 13-hydroxy-5,8,11-icosatrienoate (the major product), 11-hydroxy-5,8,12-icosatrienoate, 9-hydroxy-5,7,11-icosatrienoate, and two isomeric 8,11-dihydroxy-5,9,12-icosatrienoates. No prostaglandin-like, cyclized products could be identified. This report is only the second to illustrate a calcium-dependent oxidation of a poly-unsaturated fatty acid by a cyclooxygenase enzyme system and further extends the metabolic potential of Mead acid.
UR - http://www.scopus.com/inward/record.url?scp=0022834094&partnerID=8YFLogxK
M3 - Article
C2 - 3084488
AN - SCOPUS:0022834094
SN - 0021-9258
VL - 261
SP - 6719
EP - 6724
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 15
ER -