Partial purification and characterization of 1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine:acetyl-CoA acetyltransferase from rat spleen.
The enzyme 1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine: acetyl-CoA acetyltransferase (EC 2.3.1.67) was purified from rat spleen approx. 1500-fold in 1.6% yield. The specific activity of the purified enzyme was 0.317 +/- 0.089 mumol/min per mg of protein (mean +/- S.D., n = 6). The Km for the substrate acetyl-CoA was 137 +/- 13 microM and the pH optimum was about 8. Incubation of the purified enzyme was 1-O-[3H]octadecyl-2-lyso-sn-glycero-3-phosphocholine followed by electrophoresis resulted in the incorporation of radioactivity into a protein of Mr 29,000. The enzyme was most active towards 1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine as substrate, 1-palmitoyl-2-lyso-glycero-3-phosphocholine being a poor substrate. In addition, the enzyme preferred acetyl-CoA to palmitoyl-CoA or oleoyl-CoA as substrate.
D000123:Acetyltransferases / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D002845:Chromatography / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008861:Microsomes / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000201:enzymology*; D013379:Substrate Specificity
D000123:Acetyltransferases; C027628:acetyl-CoA-1-alkyl-2-lyso-sn-glycero-3-phosphocholine acetyltransferase