Phospholipase D-Catalyzed Synthesis of Phosphatidyl Aromatic Compounds

Abstract

Phospholipase D (PLD) from Streptomyces sp. was found to catalyze the transfer reaction of the dipalmitoylphosphatidyl residue from 1,2-dipalmitoyl-3-sn-phosphatidylcholine (DPPC) to an aromatic hydroxy group in a biphasic system of an organic solvent with low water solubility and acetate buffer. The following phosphatidyl aromatic compounds were synthesized: 1,2-dipalmitoyl-3-sn-phosphatidylphenol (1), 1,2-dipalmitoyl-3-sn-phosphatidyl-4-methoxyphenol (2, DPP-PMP), 1,2-dipalmitoyl-3-sn-phosphatidyl-4-methylphenol (3), 1,2-dipalmitoyl-3-sn-phosphatidylhydroquinone (4), 1,2-dipalmitoyl-3-sn-phosphatidyl-4-chlorophenol (5), 1,2-dipalmitoyl-3-sn-phosphatidylcatechol (6), l,2-dipalmitoyl-3-sn-phosphatidyl-3-methoxyphenol (7), 1,2-dipalmitoyl-3-sn-phosphatidyl-2-naphthol (8), and 1,2-dipalmitoyl-3-sn-phosphati-dyl-5-hydroxyindole (9). The transphosphatidylation reaction of DPPC by PLD was accompanied by hydrolysis of DPPC, and the ratios were significantly affected by both organic solvents and water contents in a biphasic system. PLD also catalyzed the transphosphatidylation reaction of DPP-PMP (2) to choline, to reproduce DPPC and liberate 4-methoxyphenol. This is the first report on the enzymatic transfer of phosphatidyl residue to aromatic hydroxy compounds.