Purification and characterization of a lysophosphatidic acid-specific phosphatase.

摘要: Lysophosphatidic acid (LPA)-specific phosphatase was purified 3300-fold from bovine brain cytosol. The purification achieved by (NH4)2SO4 fractionation and several chromatography steps, such as Q-Sepharose, DEAE-5PW, Superdex 200 heparin-Sepharose. final enzyme preparation showed a single band of molecular mass 44 kDa on SDS/PAGE under reducing conditions. activity completely dependent the presence detergents Triton X-100, CHAPS, cholate octyl-beta-glucoside. independent Mg2+; other cations were inhibitory. hydrolysed LPA specifically but not cardiolipin, tetraoleoyl-bisphosphatidic acid, ceramide 1-phosphate or sphingosine 1-phosphate, although phosphatidic slightly. 1-oleoyl at rate 1. 1 micromol/min per mg protein when assayed with X-100 mixed micelles. Km value for 38 microM. NaF N-ethylmaleimide markedly inhibited activity, propranolol had less potent inhibitory effect. LPA-specific might have an important role in elimination.