Widespread occurrence of glyceryl ether monooxygenase activity in rat tissues detected by a novel assay.
An assay was set up for glyceryl ether monooxygenase activity in tissue samples using the novel substrate 1-O-pyrenedecyl-sn-glycerol and high-performance liquid chromatographic analysis of reaction mixtures with fluorescence detection, allowing robust detection of enzymatic activity in microgram amounts of tissue homogenates. The activity partially purified from rat liver strictly depended on the presence of a tetrahydropteridine. Tetrahydrobiopterin-dependent glyceryl ether monooxygenase activity was observed in all rat tissues tested except female heart, with highest activities in liver, intestine, and cerebellum. Activity was not uniformly distributed in brain: it was higher in cerebellum than in striatum or cortex. These data demonstrate that tetrahydrobiopterin-dependent glyceryl ether monooxygenase is found not only in liver and the gastrointestinal tract but also in brain and other organs of the rat and provide an additional goal for tetrahydrobiopterin biosynthesis in these organs.
Werner
Ernst R
ER
Division of Biological Chemistry, Biocenter, Innsbruck Medical University, A-6020 Innsbruck, Austria. ernst.r.werner@i-med.ac.at
Hermetter
Albin
A
Prast
Helmut
H
Golderer
Georg
G
Werner-Felmayer
Gabriele
G
D000818:Animals; D002531:Cerebellum / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005995:Glyceryl Ethers / Q000737:chemistry / Q000378:metabolism*; D007422:Intestines / Q000201:enzymology; D008297:Male; D008832:Microchemistry / Q000379:methods; D008862:Microsomes, Liver / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000032:analysis / Q000378:metabolism*; D008956:Models, Chemical; D011621:Pteridines / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D005995:Glyceryl Ethers; D011621:Pteridines; C045357:5,6,7,8-tetrahydropteridine; D006899:Mixed Function Oxygenases