Biosynthesis and structure of a new intermediate between farnesyl pyrophosphate and squalene

G Popják, J Edmond, K Clifford, V Williams
1969 Journal of Biological Chemistry  
The intermediate, discovered by Rilling, between farnesyl pyrophosphate and squalene was synthesized in milligram quantities with yeast subcellular particles from farnesylJ4Cpyrophosphate and from farnesyl-l-3H&4C-pyrophosphate. The 3H : l4C ratio in the new squalene precursor was found to be identical with that in the farnesyl pyrophosphate, whereas the ratio in squalene was close to the expected value of 0.75 relative to the ratio either in farnesyl pyrophosphate or in the precursor. The
more » ... precursor. The squalene precursor is optically active and gives a normal optical (dextro) rotatory dispersion curve. From nuclear magnetic resonance and mass spectrometric studies, and from chemical degradation, it is concluded that this squalene precursor is the cyclic pyrophosphoryl ester of squalene-lO,ll-glycol. The metabolism of farnesyl pyrophosphate by the yeast subcellular particles yields, in addition to the squalene precursor, free farnesol, some nerolidol, farnesene, and also the cyclic monophosphate (phosphodiester) of squalene-10, llglycol. The latter is not converted into squalene with liver by guest on March 24, 2020 Downloaded from Squalene Precursor Vol. 244, No. 7 EXPERIMENTAL PROCEDURE Enzymes * In some preparations a small, as yet unidentified, radioactive component appeared between 185 and 225 ml of effluent. by guest on March 24, 2020
pmid:4388617 fatcat:4v4x4qjvenbxlmswc65umpj4ai