Purification and properties of the membrane-bound CDP-diglyceride synthetase from Escherichia coli.

摘要: The enzyme CDP-diglyceride synthetase (CTP: phosphatidate cytidylyltransferase; EC 2.7.7.41) has been purified to 90% homogeneity from Escherichia coli cells that overproduce the 50-fold through use of recombinant DNA technology. purification required different detergents at each step, illustrating refractory hydrophobic nature this protein. Apparent physical effects EDTA on were also utilized in purification. an apparent minimum subunit mass 27,000 daltons, as estimated by polyacrylamide gel electrophoresis presence sodium dodecyl sulfate. amino acid composition protein was determined, and it correlates well with theoretical product cds gene, sequence which is reported accompanying paper (Icho, T., Sparrow, C. P., Raetz, R. H. (1985) J. Biol. Chem. 260, 12078-12083). pure displays surface dilution kinetics when assayed Triton X-100. As previously suggested basis studies using partially preparations, mechanism sequential, computer-calculated kinetic constants are herein. substrate specificity investigated. This first time any source, despite fact essential for phospholipid biosynthesis all organisms.