Phosphatidylethanolamine N-methyltransferase (PEAMT) (PEMT) (EC 2.1.1.17) (EC 2.1.1.71) (PEMT2) (Phospholipid methyltransferase) (PLMT)
1_MTRLL 6_ GYVDP 11_ LDPSF 16_ VAAVI 21_ TITFN 26_ PLYWN 31_ VVARW 36_ EHKTR 41_ KLSRA 46_ FGSPY 51_ LACYS 56_ LSVTI 61_ LLLNF 66_ LRSHC 71_ FTQAM 76_ LSQPR 81_ MESLD 86_ TPAAY 91_ SLGLA 96_ LLGLG 101_ VVLVL 106_ SSFFA 111_ LGFAG 116_ TFLGD 121_ YFGIL 126_ KEARV 131_ TVFPF 136_ NILDN 141_ PMYWG 146_ STANY 151_ LGWAI 156_ MHASP 161_ TGLLL 166_ TVLVA 171_ LTYIV 176_ ALLYE 181_ EPFTA 186_ EIYRQ 191_KASGS
1: Catalyzes the three sequential steps of the methylation pathway for the biosynthesis of phosphatidylcholine, a critical and essential component for membrane structure (PubMed:12431977, PubMed:15927961). Uses S-adenosylmethionine (S-adenosyl-L-methionine, SAM or AdoMet) as the methyl group donor for the methylation of phosphatidylethanolamine (1,2-diacyl-sn-glycero-3-phosphoethanolamine, PE) to phosphatidylmonomethylethanolamine (1,2-diacyl-sn-glycero-3-phospho-N-methylethanolamine, PMME), PMME to phosphatidyldimethylethanolamine (1,2-diacyl-sn-glycero-3-phospho-N,N-dimethylethanolamine, PDME), and PDME to phosphatidylcholine (1,2-diacyl-sn-glycero-3-phosphocholine, PC), producing S-adenosyl-L-homocysteine in each step (PubMed:12431977, PubMed:15927961). Responsible for approximately 30% of hepatic PC with the CDP-choline pathway accounting for the other 70% (Probable)
2: Catalyzes the three sequential steps of the methylation of 1,2-diacyl-sn-glycero-3-phospho-N-methylethanolamine (PMME) to 1,2-diacyl-sn-glycero-3-phospho-N,N-dimethylethanolamine (PDME) more efficiently than isoform 2 (PubMed:20860552). Induces increase in PC species with longer polyunsaturated chains than isoform 2 (PubMed:20860552)
3: Produces a higher increase in the level of PC species containing long chains with three double bonds than isoform 1