Glyceryl-ether Monooxygenase [EC 1.14.16.5J Part V: Some Aspects of the Stoichiometry

Abstract

A stoichiometry of one is found for the reaction between RS-batyl alcohol and 6-methyl-5,6,7,8-tetrahydropterin catalysed by glyceryl-ether monooxygenase during the first two minutes. The apparent decoupling of these two substrates after the first two minutes of reaction is discussed. The stoichiometry of the oxidation of 6-methyl-5,6,7,8-tetrahydropterin [to quinonoid 6-methyl-7,8(6H)-dihydropterinJ to the conversion of NADH to NAD in the monooxygenase-dihydropteridine reductase coupled reaction is ca one at concentrations of 6-methyl-5,6,7,8-tetrahydropterin less than 100 μM. At higher concentrations of the tetrahydropterin the ratio decreases and it is shown to be due to product inhibition of the reductase. R( +)- and S( - )-6-Methyl- 5,6,7,8-tetrahydropterin are about equally effective substrates for glyceryl-ether monooxygenase. A new and convenient synthesis of 1-14C-batyl alcohol is reported.

Keywords

• glyceryl-ether monooxygenase
• direct spectrophotometric and dhpr-coupled assays
• 1-14c-batyl alcohol
• 6-methyl-5,6,7,8-tetrahydropterin
• stereospecificity
• stoichiometry