earticle

영어

Phospholipase D (PLD, EC 3.1.4.4) catalyzes hydrolysis of phospholipids resulting phosphatidic acid (PA) and alcohols. PLD catalyzes alcohol head group exchanging reaction known as transphosphatidylation reaction in presence of appropriate alcohol. Because of transesterification propensity, PLDs are proved to be bioindustrially important and a significant attention is being given in the search for such enzymes from wide variesties of sources, especially from microbes. More importantly, it produces scarce and commercially important phospholipids such as phosphatidylserine. Although there are a huge number of literatures found dealing with purification of extracellular PLD, only a few are from intracellular PLD. a membrane-bound phospholipase D was partially purified from the strain using sequential chromatographic steps after ammonium sulfate precipitation. The enzyme activity was found maximum at pH 8.0 and 60 °C. It was highly stable at or below 60 °C and between pH 8.0 and 10.0, indicating that it is an alkaline thermostable enzyme. Almost all detergents, except, Triton X-100 and CHAPS, suppressed the enzyme activity by various extents. Metal ions and detergents showed varied effect in the enzyme activity. Triton X-100, slightly enhanced the activity at 0.25%, however, beyond this concentration it suppressed the in concentration dependent manner.