The substrate requirements of phospholipase D

The hydrolysis rates of different diphosphates, compared with the one obser ved with natural phosphatidylcholine, are used to identify the molecular ba sis for phospholipase D (PLD) catalysis. Experimental data strongly support the idea that PLD is a rather generic phosphodiesterase with very wide sub strate specificity and a net preference for Lipophilic substrates. The pres ence of choline in the polar head is not required for activity although it improves hydrolysis efficiency. Choline esters are found to be substrates f or PLD hydrolysis, but only with long chain fatty acids. (C) 2001 Elsevier Science B.V. All rights reserved.