title: Specificity and selectivity of diacylglycerolphosphate synthesis in Escherichia coli.
abstract: The glycerolphosphate and 1-acylglycerolphosphate acyltransferase systems Escherichia coli membranes show relatively low specificities for acylcoenzymes A when maximal velocities for the respective acyl-coenzymes A are compared. However, the selectivities for palmitate and oleate in the acylations of the 1- and 2-positions of glycerolphosphate moiety, respectively, are higher at lower concentrations of acceptors in the presence of an equimolar mixture of palmitoyl-CoA and oleoyl-CoA. More 1-palmitoyl-2-oleoyl-glycerolphosphate species and less other species were synthesized at lower concentrations of glycerolphosphate. The fatty acyl moiety at the 1-position of 1-acylglycerolphosphate did not influence significantly the specificity for acyl-coenzymes A of the 1-acylglycerolphosphate acyltransferase system. Thus, the acceptor concentrations being kept low in vivo and in vitro are important for the highly selective incorporations of saturated and unsaturated fatty acids into the 1- and 2-positions of diacylglycerolphosphate, respectively, in the presence of mixtures of saturated and unsaturated acyl-coenzymes A while these acyltransferase systems exhibit relatively low specificies for acyl-coenzymes A when the respective maximal velocities are compared.
mesh_terms: D000217:Acyltransferases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005992:Glycerol-3-Phosphate O-Acyltransferase / Q000378:metabolism*; D010712:Phosphatidic Acids / Q000096:biosynthesis*; D013329:Structure-Activity Relationship
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D010712:Phosphatidic Acids; D000217:Acyltransferases; D005992:Glycerol-3-Phosphate O-Acyltransferase