Hexokinase expression

Using the expression x/(lmM - x) = 1500 ( 10 mM)/ x, one can solve the quadratic equation or iteratively estimate the value of x that satisfies the equation. This would place x at about 0.99994, indicating that 99.99% of the ATP would be depleted if the hexokinase reaction equilibrium is reached. 

As written, the above expression helps one to recognize that hexokinase can be used to maintain the [ADP]/... 

Smith, T.A. (2000) Mammalian hexokinases and their abnormal expression in cancer. Br. J. Biomed. Sci. 57, 170-178. 

A review of the four hexokinase isozymes of mammals their properties and tissue distributions and their expression during the development of tumors. 

M. M. Katabi, H. L. Chan, S. E. Karp, and G. Batist, Hexokinase type II a novel tumor-specific promoter for gene-targeted therapy differentially expressed and regulated in human cancer cells, Hum. Gene Ther. 70 155 (1999). 

Liu F, Dong Q, Myers AM, Fromm HJ. 1991. Expression of human brain hexokinase in Escherichia coli Purification and characterization of the expressed enzyme. Biochem Biophys Res Commun 177 305-311. 

Cimino M, Balduini W, Marini P, Cattabeni F, Court JA, Bianchi M, Magnani M (1998) Expression of hexokinase mRNA in human hippocampus. Mol Brain Res 5J 297-300. 

The Kf for glucokinase, a liver-specific enzyme, is 20 mM. (We shall use the expression here, even though some hexokinases studied do not follow Michaelis-Menten kinetics, and the term [S]q3 might be more appropriate. Not aU enzymes have a but they do all have a substrate concentration that gives rise to V /2. 

Various PET tracers have been developed for tumors, so they present different aspects of metabolism in tumor. The most widely used radiopharmaceutical in the clinic to detect for tumor is the glucose analog 2-[ F]fluoro-2-deoxy-d-glucose (1 F-FDG). (12) Like glucose, F-FDG is transported into cells via the glucose transporters and phosphorylated by the enzyme hexokinase. Tumors cells have increased expression of glucose transporters and hexokinase, which in turn. 

Nevertheless, there have been some successful attempts to enhance CA production through indirect means. Disruption of the gene-encoding trehalose-6-phosphate synthase A (T6PSA) led to decreased inhibition of hexokinase by trehalose-6-phosphate, which initiated citric acid accumulation earlier. Antisense expression of Brsa-25... 

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