Biosynthesis of alkyl-ether containing lipid from dihydroxyacetone phosphate.

نویسنده

  • A K Hajra
چکیده

A lipid, stable to alkaline methanolysis, is formed when liver mitochondria or brain microsomes are incubated with dihydroxyacetone phosphate, long chain alcohol, ATP, CoA, NaF and Mg*. The lipid has been identified as alkyl dihydroxyacetone phosphate. This lipid is reduced by NADPH to 1-alkyl glycerol3-phosphate and is further acylated to form 1-alkyl 2-acyl glycerol-3-phosphate. The ether-containing lipids are very widespread in nature (1). Recently Snyder and coworkers (2,3) presented evidence that these lipids are formed in tumor cells from long chain alcohol and D-glyceraldehyde-3-phosphate (GADP)'. During the course of investigation of DHAP-containing lipid, it was found that an alkyl-ether-containing lipid is biosynthesized in normal guinea pig liver mitochondria or in mouse brain microsomes from long chain alcohol and DHAP in the presence of necessary cofactors. Evidence presented here indicates that GADP is not an obligatory intermediate in this system. Materials and Methods: 1-14C-Hexadecanol was purchased from Amersham/Searle (Des Plaines). 32 P-Labeled DHAP was prepared by enzymatic phosphorylation of dihydroxyacetone (4). Labeled fructose-6-phosphate was prepared by enzymatic (hexokinase) phosphorylation of fructose by y32 P-ATP and oxidized with periodic acid (5) to form =P-GADP. Crystalline enzymes were from Boehringer-Mannheim (New York). Hexadecanol was emulsified in Tris-HCl buffer (0.1 M, pH 7.6) with Triton X-100 (Rohm and Haas, Philadelphia). Incubation conditions are described in Table 1. The reaction was stopped by adding 4.5 ml chloroform-methanol (l-2) and the lipid was extracted as

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عنوان ژورنال:
  • Biochemical and biophysical research communications

دوره 37 3  شماره 

صفحات  -

تاریخ انتشار 1969