3- Phosphoglycerate determination

The stmcture was determined to 2.8 A resolution in the laboratory of Tom Steitz, Yale University, (d) The glycolytic enzyme phospho-glycerate mutase, which catalyzes transfer of a phos-phoryl group from carbon 3 to carbon 2 In phosphoglycerate. The structure was determined to 2.S A resolution in the laboratory of Herman Watson, Bristol University, UK. (Adapted from J. Richardson.)... 

The simultaneous determination of dissolved organic carbon and phosphorus is feasible [39]. Phosphoglyceric acid (1 g equivalent P) was added to membrane-filtered, pre-irradiated seawater, and the phosphate was measured before and after ultraviolet irradiation using an autoanalyser. The recovery of organic phosphorus was 100%. 

Phosphorus was determined in the extracts by the spectrophotometric method of Murphy and Riley [63] and Stickland and Parsons [96]. In Table 12.10 results are shown obtained upon applying the procedure to the determination of total phosphorus in solutions of calcium phosphoglyceric acid. 

Phosphoglycerate kinase is a protein composed of two structural domains of approximately equal molecular weight (N-terminal do-mainMr 20,814 C-terminal domain Afr 23,735). The crystallographic structure has been determined (Watson et al., 1982) and can be used to calculate the hydrophobic surface exposed to water on total or partial unfolding as well as the number of hydrogen bonds and other bonds involved in the stabilization of the folded conformation. 

Adams H (1963) Adenosine-5 -triphosphate determination with phosphoglycerate kinase. In Bergmeyer HU (ed) Methods of enzymatic... 

The stable bisubstrate ligands 109 of phosphoglycerate kinase (PGK) in which adenylate is attached to non-scissile 1,3-bisphosphoglycerate analogues have been described. The analogues form high-affinity complexes with PGK as determined by H NMR. 

At regular intervals the immune status of the patient was assessed as well as the serum content and the urinary excretion of purine- and pyrimidine metabolites according to methods described in detail previously (6,8,10). The (deoxy)ribonucleotide content of the erythrocytes was analyzed by HPLC Ul)- Perchloric acid extracts of freshly withdrawn blood were made according to Cohen et al. (2) with minor modifications. In order to analyze deoxyribo-nucleotides the neutralized perchloric acid extracts were treated with sodium periodate according to Garret and Santi (12). 2,3 Di-phosphoglycerate (2,3-DPG) in the erythrocytes was determined as previously described (13). Ecto-5 -nucleotidase on intact lymphocytes was determined as described(14). Adenosine deaminase activity of the lymphocytes was determined essentially according to van Laar-hoven et al. (15). 

The combination of metal coordination and cleft-like preorganization has been exploited by Anslyn with receptor 54 to bind 2,3-bisphosphoglycerate (55). The association constant for 55 binding was measured by an indicator displacement method in 1 1 water/CH30H, and determined to be 8 X 10 M Structurally similar phosphoglycerates, in which of one phosphate is removed, gave binding constants 80-180 times lower than that of 55. This result established that receptor 54 was very selective for 55. 

The two triose phosphates may be distinguished chemically. Both sugar phosphates are rapidly split by alkali at room temperatures. The oxidation of the aldehyde to phosphoglyceric acid by iodine has been used in the assay of mixtures. Only the remaining dihydroxyacetone phosphate is alkali labile. The phosphoglyceric acid may be determined by its high rotation in molybdate. 

Fig. 34. Experiment to determine which reaction is indirectly light-dependent in the secondary processes of photosynthesis. When it becomes dark the amount of 3-phosphoglyceric acid (PGA) increases, in contrast to that of the other components (modified from Baron 1967).

Fig. 6 Phosphoglycerate mutase (PGM) in spinach chloroplasts identified by the latency method. Purified, intact chloroplasts were subjected to stepwise osmotical shock by lowering the sorbitol cone, of the medium. The enzyme activity released from chloroplast was determined in the supernatant. In the latency studies, PGM exhibits an identical behaviour compared to reversible NADP-GAPDH and shikimate oxidoreductase (SORase) as marker enzymes for chloroplasts.

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