Glucose 1-phosphate kinase

All the reactions of the Calvin cycle except those catalyzed by rubisco, sedoheptulose 1,7-bisphospha-tase, and ribulose 5-phosphate kinase also take place in animal tissues. Lacking these three enzymes, animals cannot carry out net conversion of C02 to glucose. 

Glucose 6-phosphate dehydrogenase Phenylalanine ammonia lyase Rihulose 5 -phosphate kinase NADP+-malate dehydrogenase... 

The molecular weight is328 75,000, and the Km for D-fructose 1-phosphate is326 0.3 mM at an optimal327 pH of 8. No phosphorylation is observed with L-ffuctose 1-phosphate, D-mannose 6-phosphate, D-fructose 6-phosphate, D-glucose 6-phosphate, or D-glucose 1-phosphate.328 The enzyme requires Mnz+ or Mg2+ for catalytic activity,328 but K+, Rb+, and NH4+ increase the enzymic activity.329 ATP inhibits the kinase, as the ratio of concentration of Mg2+ to ATP decreases below 2 1. The ATP inhibition can be released by Mg2+. Citrate (K, 0.85 mM), D-fructose 1,6-bisphosphate (K,- 4.4 mM), and D-fructose 6-phosphate (Kj 1.0 mM) inhibit D-fructose 1-phosphate kinase competitively with D-fructose 1-phosphate.328... 

The phosphoglucomutase reaction involves continual utilization and resynthesis of the cofactor, but it cannot cause the net synthesis of glucose-1,6-diphosphate. Two mechanisms have been found to increase the amount of this cofactor in each case glucose-l-phosphate is the phosphate acceptor but the phosphate donors are different for the two enzymes involved. Glucose-l-phosphate kinase requires ATP to carry out the reaction ... 

Fig. 14.2 Cellulose biosynthetic pathway in cellulose-producing acetic acid bacteria. FIP firuc-tose-1-phosphate, F6P fructose-6-phosphate, FDP fructose diphosphate, PGA phosphogluconate GHK glucose hexokinase, FHK fructose hexokinase, IPFK fructose-1-phosphate kinase, FBP fructose blsphosphatase, PGI phosphoglucose isomerase, PGM phosphoglucomutase, UGP UDP-glucose pyrophosphorylase, G6PD glucose-6-phosphate dehydrogenase, PTS phosphotransferase system EMP Embden-Myerhoff pathway...

The biological transformations that involve ATP are both numerous and funda mental They include for example many phosphorylation reactions m which ATP trans fers one of its phosphate units to the —OH of another molecule These phosphoryla tions are catalyzed by enzymes called kinases An example is the first step m the metabolism of glucose... 

Clinical Analysis. A wide range of clinically important substances can be detected and quantitated using chemiluminescence or bioluminescence methods. Coupled enzyme assay protocols permit the measurement of kinase, dehydrogenase, and oxidases or the substrates of these enzymes as exemplified by reactions of glucose, creatine phosphate, and bile acid in the following ... 

---