Properties of a membrane-bound cardiolipin synthetase from Lactobacillus plantarum.
Cardiolipin (CL) synthetase of Lactobacillus plantarum 17-5 catalyzed the stoichiometric conversion of 2 mol of phosphatidylglycerol to 1 mol of CL. The enzyme activity was linear with time for 30 min at 37 C and with protein concentration between 20 and 200 mug of protein per ml. The enzyme was membrane associated, had a pH optimum of 5.1 in phosphate buffer, and was not stimulated by Mg2+, and the activity was not affected by the addition of ethylenediaminetetraacetic acid, cytidine diphosphate diglyceride, or cytidine triphosphate. The reaction was inhibited about 95% by Triton X-100 (0.5% final concentration) and by CL, the end product of the reaction. The activity of this enzyme was studied as a function of growth. The CL synthetase specific activity was highest during the early and midexponential growth phases, as was the cellular content of CL. The results demonstrate a correlation between enzyme-specific activity and lipid content of the cells.
D002308:Cardiolipins / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology; D003567:Cytidine Diphosphate Diglycerides / Q000494:pharmacology; D003597:Cytosine Nucleotides / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007778:Lactobacillus / Q000201:enzymology* / Q000254:growth & development; D008274:Magnesium / Q000494:pharmacology; D010770:Phosphotransferases / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology
D002308:Cardiolipins; D003567:Cytidine Diphosphate Diglycerides; D003597:Cytosine Nucleotides; D011092:Polyethylene Glycols; D004492:Edetic Acid; D010770:Phosphotransferases; D008274:Magnesium