GLYCERYL-ETHER MONOOXYGENASE (EC-1.14.16.5) - NATURE OF THE GLYCERYL-ETHER LIPID SUBSTRATES IN AQUEOUS BUFFER

The kinetics of inhibition of glyceryl-ether monooxygenase with 6-meth yl-5,6,7,8-tetrahydropterin as cofactor (saturating) by the detergent Mega-10 with batyl alcohol and (1-hexadecyloxy)-2-hydroxypropane-1-pho sphocholine as substrates exhibited noncompetitive inhibition with app arent K-i values of 1.74 +/- 0.37 mM and 185 +/- 23 mu M, respectively . Inhibition by octadecan-1-ol (with batyl alcohol as substrate in the presence of 2.3 mM Mega-10) was competitive with an apparent K-i valu e of 765 +/- 80 mu M. The critical micelle concentration values of var ious solutions of Mega-10 were determined and used to show that the ac tive ether-lipid substrates were in micelle form (for a water soluble substrate) or mixed micelle form (for substrates solubilised with Mega -10).