Glyceric acid phosphate

Glycogen — hexose — hexose monophosphate —> hexose diphosphate —> glycerose phosphate + dihyroxyacetone phosphate —> glyceric acid phosphate + glycerol phosphate. Glyceric acid... 

Glyceric acid Phosphates Glycerol Glyceric acid Diglycerol Glycosyl-glycerol... 

R)-Glyceraldehyde. Fischer projection of, 976 molecular model of, 976, 977 Glyceric acid, structure of. 753 Glycerol, catabolism of, 1132-1133 s/i-Glycerol 3-phosphate, naming of, 1132... 

Sugar The hydrolysis of sucrose in the intestine produces both glucose and fructose, which are transported across the epithelial cells by specific carrier proteins. The fructose is taken up solely by the liver. Fructose is metabolised in the liver to the triose phosphates, dihydroxy-acetone and glycer-aldehyde phosphates. These can be converted either to glucose or to acetyl-CoA for lipid synthesis. In addition, they can be converted to glycerol 3-phosphate which is required for, and stimulates, esterification of fatty acids. The resulting triacylglycerol is incorporated into the VLDL which is then secreted. In this way, fructose increases the blood level of VLDL (Chapter 11). 

The interconversions of the phosphorylated three-carbon acids—phosphenolpyruvate, glycerate-2-phosphate, and glycerate-3-phosphate—have already been discussed in this chapter. This pool is linked to the fructose-1,6-bisphos-... 

Inspection of the amino acid biosynthetic pathways shows that all amino acids arise from a few intermediates in the central metabolic pathways (see fig. 21.1). Amino acids de-rived from a common intermediate are said to be in the same family. For example, the serine family of amino acids, which includes serine, glycine, and cysteine, all arise from glycerate-3-phosphate (see fig. 21.1). The carbon flow from the central metabolic pathways to amino acids is a regulated... 

Before the next phase of glycolysis can occur, the phospho-glyceric acid must be internally rearranged, by the transfer of the remaining phosphate from position 3 to position 2 of the molecule. The rearrangement is brought about by the enzyme phospho-glyceromutase ... 

Location. Plant fatty acid synthesis appears to be limited to chloroplasts. A chloroplast isozyme of pyruvate dehyrogenase catalyzes the conversion of pyruvate to acetyl-CoA. Pyruvate is also derived from glycerate-3-phosphate, an intermediate in the Calvin cycle, a biosynthetic pathway in which plants incorporate COz into sugar molecules. (The Calvin cycle is discussed in Chapter 13.)... 

---