rac-Glycerol 1:2-cyclic phosphate 2-phosphodiesterase, a new soluble phosphodiesterase of mammalian tissues.
1. A soluble phosphodiesterase is present in mammalian tissues which rapidly hydrolyses enantiomorphs of rac-glycerol 1:2-cyclic phosphate, producing rac-glycerol 1-phosphate. 2. The enzyme has been purified up to 1700-fold by a combination of acetone precipitation and chromatography on DEAE-Sephadex A-50, Sephadex G-150 and hydroxyapatite. 3. The Km with glycerol cyclic phosphate as substrate is 7.2 mM, and the pH optimum broad (6.9--7.5). The molecular weight (by gel filtration) of the enzyme is approx. 35500. 4. The phosphodiesterase has no requirement for Ca2+ or Mg2+, but is stimulated by reducing agents (cysteine, dithiothreitol) and Fe2+. 5. The purified phosphodiesterase preparation also hydrolysed 3':5'-cyclic AMP, producing 5'-AMP exclusively, and 2':3'-cyclic AMP, forming 3'-AMP and 2'-AMP in the ratio 7:3. Bis-(p-nitrophenyl) phosphate was slowly hydrolysed, but other phosphodiesters tested were not attacked. 6. The phosphodiesterase is inhibited by theophylline and o-phenanthroline. It is inhibited by Pi and by a variety of phosphomonoesters, of which certain aromatic primary phosphates are particularly effective.
D000818:Animals; D002413:Cations, Divalent / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D005994:Glycerophosphates; D010726:Phosphodiesterase Inhibitors; D010727:Phosphoric Diester Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D013379:Substrate Specificity; D014018:Tissue Distribution
D002413:Cations, Divalent; D005994:Glycerophosphates; D010726:Phosphodiesterase Inhibitors; D010727:Phosphoric Diester Hydrolases