Squash glycerol-3-phosphate (1)-acyltransferase. Alteration of substrate selectivity and identification of arginine and lysine residues important in catalytic activity.

Glycerol-3-phosphate 1-acyltransferase is a soluble chloroplast enzyme involved in glycerol-lipid biosynthesis associated with chilling resistance in plants (). Resistance is associated with higher selectivity for unsaturated acyl substrates over saturated ones. In vitro substrate selectivity assays performed under physiologically relevant conditions have been established that discriminate between selective and non-selective forms of the enzyme.