| Literature DB >> 25437 |
F Hirata, O H Viveros, E J Diliberto, J Axelrod.
Abstract
Two methyltransferases involved in the methylation of phosphatidylethanolamine to form phosphatidylcholine were demonstrated in a microsomal fraction of bovine adrenal medulla. The first methyltransferase catalyzes the methylation of phosphatidylethanolamine to form phosphatidyl-N-monomethylethanolamine. This enzyme has an optimum pH of 6.5, a low Km for S-adenosyl-L-methionine (1.4 micron), and an absolute requirement for Mg2+. The second methyltransferase catalyzes the two successive methylations of phodphatidyl-N-monomethylethanolamine to phosphatidyl-N,N-dimethylethanolamine and phosphatidylcholine. In contrast to the first methyltransferase, it has an optimum pH of 10 and a high Km for S-adenosyl-L-methionine (0.1 mM) and does not require Mg2+.Entities:
Mesh:
Substances:
Year: 1978 PMID: 25437 PMCID: PMC392410 DOI: 10.1073/pnas.75.4.1718
Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN: 0027-8424 Impact factor: 11.205