THE INFLUENCE OF ORGANIC-SOLVENTS ON PHOSPHOLIPID TRANSFORMATIONS BY PHOSPHOLIPASE-D IN EMULSION SYSTEMS

Phospholipase D is an accepted tool in the transformation of phospholi pids which is preferably performed in aqueous-organic emulsion systems . The hydrolysis of phosphatidylcholine and its transphosphatidylation with 1-butanol are extremely different in hexane and diethyl ether. S mall amounts of primary ol secondary alcohols (<2%) are able to mediat e the otherwise very slow reaction in hexane/buffer. The reaction syst ems were characterized by X-ray scattering, water content in the organ ic phases, and interfacial areas and tensions. The different packing d ensity of the amphiphilic phosphatidylcholine molecules at the interfa ce where the enzymatic reaction mainly takes place appears to be one o f the major causes for the large solvent effects. (C) 1997 by Elsevier Science Inc.