The mouse plasma PAF acetylhydrolase: II. It consists of two enzymes both associated with the HDL.
The PAF acetylhydrolase (PAF-AH) of mouse plasma was characterised as to its lipoprotein subclass and apolipoprotein association. Association with plasma lipoproteins was established by cholesteryl-hemisuccinate agarose affinity chromatography while electrophoretic and electrofocusing studies demonstrated almost exclusive association with the HDL-VHDL. Fractionation of [4-14C]cholesterol-labelled plasma on a Bio-Gel A-5m column established that 1% of the enzymic activity was associated with the VLDL-LDL, 4.5% with the HDL1, 80% with the HDL2-HDL3 and 15% with the VHDL. Electrophoresis of the solubilised, HDL2-HDL3 bound enzyme gave two peaks of activity with mobilities of 0.29 and 0.49 and a distribution of the recovered activity of 78 and 22%, respectively. The VHDL associated activity on similar analysis gave a 25 and 75% distribution. These findings showed that two enzymes, both associated with the HDL and VHDL fractions, constitute the PAF-AH activity of mouse plasma. Further fractionation of the HDL2-HDL3 bound activity on heparin-agarose established that 70% of the recovered activity was bound to the apo-E containing HDL.
Tsaoussis
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V
Institute of Biology, National Centre for Scientific Research Demokritos, Aghia Paraskevi Attikis, Greece.
Vakirtzi-Lemonias
C
C
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D000818:Animals; D001057:Apolipoproteins E / Q000378:metabolism; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood*; D008297:Male; D051379:Mice; D010741:Phospholipases A / Q000097:blood*; D051381:Rats
D001057:Apolipoproteins E; D008075:Lipoproteins, HDL; C026277:very high density lipoproteins; D010741:Phospholipases A; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase