Ester, biosynthesis

O Hagan D and Robins RJ (1998) Tropic acid ester biosynthesis in Datura stramonium and related species. Chem Soc Rev 27, 207-212. 

Kayama, M. and Nevenzel, J. (1974). Wax ester biosynthesis by midwater marine animals. Marine Biology 24,79-285. 

A considerable amount of knowledge has accumulated about how pheromone components are produced in female moths since the first pathway was identified some 20 years ago. It appears that most female moths produce their pheromone through modifications of fatty acid biosynthesis pathways. For moths that utilize aldehydes, alcohols, or esters biosynthesis occurs in the pheromone gland. The exceptions are those that utilize linoleic or linolenic acids, which must be obtained from the diet. However, modifications of these fatty acids occur in the gland. For moths that utilize hydrocarbons or epoxides of hydrocarbons, the hydrocarbon is produced in oenocyte cells and then transported to the pheromone gland where the epoxidation step takes place. 

Ruegger, M., Meyer, K., Cusumano, J.C. and Chappie, C. (1999) Regulation of ferulate-5-hydroxylase expression in Arabidopsis in the context of sinapate ester biosynthesis. Plant Physiol, 119,101-10. 

Aromatic esters have been synthetised in ionic liquids. In this context, the lipase-catalysed acylation of 2-hydroxymethyl-l,4-benzodioxane with vinyl acetate was carried out in two ionic liquids, [bmim+][PFg ] and [bmim+][BF ] [14], They found better or comparable conversion in these unconventional media than in conventional organic solvents. Another interesting example of aromatic ester biosynthesis in ILs was reported by Vidyaa and Chadhaa [13]. These authors carried out the transesteii-fication of ethyl 3-phenylpropanoate with 11 alcohols catalysed by in [bmim ] [PFg ], [bmim "][BF "] and [bmim+llNTf "] as reaction media. 

Fig. 3. The effect of purified SCP on rat liver microsomal cholesterol ester biosynthesis, using [4- C]cholesterol as substrate. The microsomal conversion of cholesterol to cholesterol esters was conducted as described [22].

THE PHENYLPROPANOID PATHWAY IN ARABIDOPSIS LESSONS LEARNED FROM MUTANTS IN SINAPATE ESTER BIOSYNTHESIS... 

Rodriguez, G.M, Tashiro, Y., and Atsumi, S. (2014) Expanding ester biosynthesis in Escherichia coli. Nat Chem. Biol., 10, 259-265. 

Li, F Wu, X Lam, P Bird, D Zheng, H Samuels, L Jetter, R Kimst, L. Identification of the wax ester synthase/acyl-coenzyme A Diacylglycerol acyltransferase WSDl required for stem wax ester biosynthesis m. Arabidopsis. Plant Physiol, 2008, 148, 97-107. 

Esters can be synthesised chemically or biologically in beer. Brewing yeasts are undoubtedly the principal ester producers in beer fermentation. Esters and their formation mechanisms in brewing S. cerevisiae yeast strains have attracted much research attention and have been reviewed several times (Peddie, 1990 Pires et al., 2014 Saeiens, Delvaux, Verstrepen, Thevelein, 2010 Verstrepen et al., 2003). Therefore, it is beyond the scope of this section to elaborate the details of ester biosynthesis, and interested readers are referred to these review articles for further information. However, a summary of ester biosynthesis based on these reviews are provided below. 

Reversal of an esterase-type reaction was the only mechanism demonstrated for wax ester biosynthesis until 1967 (Kolattukudy, l%7a). Under physiological conditions an acyl transfer mechanism would be expected to be involved in such ester synthesis. Because of the high thioesterase activ-... 

Reexposure to air enhances the production of methanol, some esters, and acetic acid (m/z 43, m/z 61, and m/z 75) for three of the four cultivars. The C6 compound production decreases for these three cultivars, but remains at values slightly higher than initial aerobic conditions. Reexposure to aerobic conditions for the fourth cultivar (Pink Lady) results in a fast decrease of all the compounds to production rates lower than initial aerobic conditions. Low O2 storage decreases ester content and enzymatic activity responsible for ester biosynthesis in apples [26]. These measurements show that even when exposed to short anaerobic treatment (24 h). Pink Lady suffered low oxygen injuries, by losing its aroma and flavor. 

D. S., Bostick, B.C. (1993) Study of ester biosynthesis in relation to harvest maturity and controlled-atmosphere storage of apples (Malus domestica Borkh.). Proceedings of the 6th International Controlled Atmosphere Research Conference, Cornell University, Ithaca, NY. 

When whole strawberries were cut into pieces and incubated with alcohols and acids, it has been shown that if they were cut into two or four pieces, the formation of the acetate esters increased, while cutting them into eight pieces dramatically depressed the formation of esters. Moreover, no ester formation was observed when strawberry was homogenized (Yamashita et al. 1975). Gilliver and Nursten (1976) showed that without adding banana slices, it was impossible to produce esters in aqueous solutions containing lower alcohols and either acetyl or butyryl CoA, or acetic or butyric anydride. They concluded that there is need for enzymes and/or cofactors from the fruit slice for ester biosynthesis. 

Fellman JK, Mattinson DS, Bostick BC, Mattheis JP, Patterson ME (1993) Ester biosynthesis in Rome apples subjected to low-oxygen atmospheres. Postharvest Biol and Technol 3 201-214... 

Wax ester biosynthesis probably involves an acyl transfer mechanism. The high thioesterase activity found in crude plant extracts makes it difficult to demonstrate acyl-CoA involvement in wax ester synthesis. However, partial purification of an acetone powder extract from the leaves of B. oleracea gave a protein fraction that catalyzed an acyl-CoA-dependent esterification of fatty alcohols (222). Additionally the acetone powder extract from B. oleracea leaves appeared to catalyze the direct transfer of acyl moieties from phospholipids to fatty alcohols. The leaf extract also catalyzed under appropriate conditions the esterification of fatty alcohols to free fatty acids. The transacylase mechanism is likely to be the main mechanism of wax ester synthesis in vivo. The fact that labeled wax esters were synthesized by a membrane-bound microsomal fraction from Hordeum vulgare leaves following incubation with radioactive alcohols, but not after incubation with free fatty acids (17), is consistent with the proposed acyl transfer mechanism. In E. gracilis the acyl-CoA reductase is functionally coupled to the acyl transferase (227). Both of these activities were solubilized from the microsomes... 

Matich, A., and Rowan, D. (2007) Pathway analysis of branched-chain ester biosynthesis in apple using deuterium labeling and enanti-oselective gas chromatography-mass spectrometry. J. Agric. Food Chem. 55, 2727-2735... 

R.E. Garcia and J.B. Mudd, Identification of an acyl donor in steryl ester biosynthesis by enzyme preparations from spinach leaves. Plant Physiol. 62 348 (1978)... 

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