Lecithin retinol acyltransferase is an enzyme that transfers an acyl group from phosphatidylcholine, also called lecithin, to retinol, producing a retinyl ester. The donor's position and the acceptor's alcohol group are part of the reaction definition; describing it merely as an enzyme that binds vitamin A would omit its chemical function.[ref]
Lecithin retinol acyltransferase in IUBMB Enzyme Nomenclature. EC 2.3.1.135, accepted reaction and sn-1 acyl transfer
This reaction supplies ester forms for retinoid storage and metabolism. It is distinct from changing retinyl-chain geometry, even though both operations occur in the broader visual cycle.[ref]
Lecithin retinol acyltransferase in IUBMB Enzyme Nomenclature. Comments, ester products and substrate recognition
A 2005 experiment illustrates why the distinction matters. Cultured cells expressing RPE65 required coexpression of lecithin retinol acyltransferase to provide the ester substrate for the measured production of 11-cis-retinol.[ref]
RPE65 is the isomerohydrolase in the retinoid visual cycle by Gennadiy Moiseyev and others. Abstract, coexpression requirement
Missing product can therefore reflect a failure of upstream substrate supply rather than a failure of the downstream enzyme itself. Measuring both steps helps distinguish a pathway requirement from the identity of the catalyst performing a particular transformation. Articles by others on the same topic
There are currently no matching articles.