Alkylphosphate esters as inhibitors of phospholipase D

Alkylphosphate esters were shown to be potent inhibitors of phospholipase D. Using phosphatidyl choline/sodium dodecylsulfate (2:1) as substrate, IC50 values were determined for alkylphosphocholines of different chain length (C10-C18) and for various octadecylphosphate esters with different polar head groups. The inhibitory potency strongly increased with increasing chain length of the alkyl chain. The substitution of choline for heterocyclic nitrogen compounds or for 2-trimethylarsonio-ethanol also affected the inhibition of phospholipase D. Octadecylphosphocholine proved to be the most efficient inhibitor (IC50 = 6.4 microM).