Journal of Lipid Research, Vol 19, 309-315, Copyright © 1978 by Lipid Research, Inc.
Conversion of diphosphatidylglycerol to bis(monoacylglyceryl)phosphate by lysosomes
BJ Poorthuis and KY Hostetler
Diphosphatidyl[1',2',3'-14C]glycerol (cardiolipin) is converted to
bis(monoacylglyceryl)phosphate when incubated in vitro with rat lysosomes
at pH 4.4. The stereochemical configuration of the product is unknown. This
reaction probably takes place via lysophosphatidylglycerol, one of the
major products of diphosphatidylglycerol hydrolysis by lysosomes.
Phosphatidyl[1',2',3'- 14C]glycerol was introduced into mitochondrial
membranes by incubating mitochondria with [U-14C]sn-glycerol-3-phosphate
and cytidine diphosphate diacylglycerol. Membrane-bound
phosphatidyl[1',2',3'- 14C]glycerol is also converted to
bis(monoacylglycerol)phosphate when incubated with lysosomes in a reaction
that is dependent on the concentration of lysosomal protein and on
incubation time. These results support our previous proposal (Poorthuis, B.
J. H. M., and K. Y. Hostetler, 1976. J. Biol. Chem. 251: 4596-4602) that
bis(monoacylglyceryl)phosphate formation may require the interaction of
lysosomes with other membranes that contain the substrates for the
reaction. The stereochemistry of bis(monoacylglyceryl)phosphate
biosynthesis is discussed.