2.5.1.62 evolution the predicted sequence of ChlG of Synechocystis sp. PCC 6803 is considerably similar (35% identity) to that of Rhodobacter sphaeroides BchG, each enzyme has a high level of substrate specificity to distinguish its own substrate from the other. But the BchG activity of Synechocystis chlorophyll synthase mutant ChlGI44F and the ChlG activity of bacteriochlorophyll synthase mutant BchGF28I suggest that ChlG/EC 2.5.1.62 and BchG/EC 2.5.1.133 are evolutionarily related enzymes 738867 2.5.1.62 malfunction gene silencing in vein cells and neighboring cells reduces chlorophyll accumulation around veins by 60-90%, CO2 fixation by minor veins from the xylem stream and the amount of specific metabolites such as soluble sugars associated with carbohydrate metabolism and the shikimate pathway are reduced, the abundance of transcripts encoding components of phosphoenolpyruvate generating pathways are altered, leaf senescence, growth rate, and seed size are reduced 710282 2.5.1.62 malfunction mutant dlt4-1 is pale green and heat sensitive due to the reduced Chl content. Besides Chl synthase, Lhcb1, a light-harvesting Chl a/b-binding protein, is reduced to about 60% of the wild-type level in chlg-1. The chlG missense mutation is responsible for a light-dependent, heat-induced cotyledon bleaching phenotype. Following heat treatment, mutant chlg-1 but not wild-type seedlings accumulate a substantial level of chlorophyllide a, which results in a surge of phototoxic singlet oxygen. The mutation destabilized the chlorophyll synthase proteins and causes a conditional blockage of esterification of chlorophyllide a after heat stress. Accumulation of chlorophyllide a after heat treatment occurs during recovery in the dark in the light-grown but not the etiolated seedlings, suggesting that the accumulated chlorophyllides were not derived from de novo biosynthesis but from de-esterification of the existing chlorophylls. The triple mutant harboring the ChlG mutant allele and null mutations of chlorophyllase 1 (CLH1) and CLH2 indicates that the known chlorophyllases are not responsible for the accumulation of chlorophyllide a in chlg-1 739311 2.5.1.62 malfunction reduced enzyme activity does not result in accumulation of chlorophyllide, it causes reduced 5-aminolevulinic acid formation and Mg chelatase and ferrochelatase activity, growth is retarded, leaves are pale green (20% wild type chlorophyll content), overexpression is correlated with enhanced 5-aminolevulinic acid synthesizing capacity and more chelatase activity, the results point to a feedback control of the biosynthesis pathway, the phenotype is not distinguishable from the wild type 710291 2.5.1.62 metabolism enzyme catalyzes the last step in the chlorophyll biosynthetic pathway 710291 2.5.1.62 metabolism identification of a link between chlorophyll biosynthesis and the Sec/YidC-dependent cotranslational insertion of nascent photosystem polypeptides into membranes. This close physical linkage coordinates the arrival of pigments and nascent apoproteins to produce photosynthetic pigment protein complexes with minimal risk of accumulating phototoxic unbound chlorophylls 739294 2.5.1.62 metabolism light-harvesting-like potein 3, Lil3, participates in the regulation of chlorophyllide a esterification 739419 2.5.1.62 additional information in the presence of light or chlorophyllide, chlorophyll synthase interacts with protochlorophyllide-oxidoreductase, EC 1.3.1.33, and light-harvesting-like potein 3, Lil3 739419 2.5.1.62 additional information residue I44 is important for the substrate specificities of ChlG 738867 2.5.1.62 physiological function chlorophyll synthase is an important enzyme of the chlorophyll biosynthetic pathway catalyzing attachment of phytol/geranylgeraniol tail to the chlorophyllide molecule 737772