Carbon Glucose-6-phosphatase

Brondeau MT, Coulais C, de Ceaurriz J. 1991. Difference in liver and serum malathion carboxylesterase and glucose-6-phosphatase in detecting carbon tetrachloride-induced liver damage in rats. J AppI Toxicol 11 433-435. 

Glende EA Jr., Hruszkewycz AM, Recknagel RO. 1976. Critical role of lipid peroxidation in carbon tetrachloride-induced loss of aminopyrine demethylase, cytochrome P-450 and glucose 6-phosphatase. Biochem Pharmacol 25 21663-2170. 

Sein KT, Chu N. 1979. Liver and Kidney glucose-6-phosphatase levels in carbon tetrachlolride - and PDT - administered mice. Enzyme 24 72-74. 

Cytochrome oxidase Peroxidase, catalase Carbonic anhydrase Alcohol dehydrogenase Hexokinase Pyruvate kinase Glucose 6-phosphatase Pyruvate kinase Nitrogenase, nitrate reductase Glutathione peroxidase... 

Fig. 2.9 Synthesis of sucrose. See text (Modified from Fig. 20-13 in Berg JM, Tymoczko JL and Stiver L. Biochemistry, 5th Ed. 2002. W.H. Freeman Co., New York to also show the phosphatase step). Note The diagram of fructose in this figure (red) is rotated so that its anomeric carbon atom (C2) lies to the right of the ring structure instead of the left as in a conventional diagram. Because of the rotation, it is not obvious that the fructose bond in sucrose is in the (3-anomeric configuration. Only the glucose bond is in the a-anomeric configuration. The conventional diagrams of glucose and fructose alone and in sucrose are illustrated in Fig. 15.6.

Efficient utilization of the fructose requires phosphorylation of the glyceraldehyde. Tracer experiments show that the carbon 1 of fructose appears as both carbons 1 and 6 of glucose. This is the result of triose phosphate isomerization followed by (conventional) aldolase condensation to hexose diphosphate. The conversion of fructose diphosphate to glucose-6-phosphate requires a phosphatase and an isomerase, as discussed in the pentose phosphate pathway. 

Lastly, both glucagon and the glucocorticoid hormones, such as cortisol increase the levels of the glucogenic bypass enzymes such as fructose 1,6-bisphosphatase and glucose 6-phosphatase, and also the levels of the transaminase enzymes which release the carbon skeletons from the glucogenic amino acids. 

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