Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.1.1 (hexokinase)
 5,274 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carbamyl phosphate synthetase from Escherichia coli has been shown to use only the A isomer of adenosine-5'-[2-thiotriphosphate] in both the ATPase reaction (MgATP HCO3- leads to MgADP + Pi) and the carbamyl phosphate synthesis reaction (2MgATP + HCO3- + L-glutamine leads to 2MgADP + Pi + carbamyl-P + L-glutamate). The B isomer was less than 5% as reactive. In the reverse reaction, only the A isomer of adenosine-5'-[2-thiotriphosphate] is synthesized from adenosine-5'-[2-thiodiphosphate] and carbamyl-P as determined by 31P NMR and a coupled enzymatic assay with Cd2+- hexokinase. It is therefore proposed that carbamyl phosphate synthetase uses the same diastereomer of MgATP at both ATP sites.
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PMID:Carbamyl phosphate synthetase of Escherichia coli uses the same diastereomer of adenosine-5'-[2-thiotriphosphate] at both ATP sites. 21 Nov 24

The effect of inert coordination complexes of chromium (III) with various nucleotides on the catalytic activity of rat liver pyruvate carboxylase was determined. The chromium nucleotides are effective initial inhibitors of pyruvate carboxylase and the inhibition becomes more severe with time. The initial rate decreases for several minutes, reaching a new slower rate that is then maintained until considerable net reaction occurs. Incubation of the enzyme with chromium nucleotides in the presence of Mg2+ and HCO3- causes maximal inhibition of the reaction and linear initial rates are then observed. This effect is similar to that found with yeast hexokinase (Dannenberg, K.D., and Cleland, W.W. (1975) Biochemistry 14, 28-39). The specificity of the carboxylase toward the nucleotide complexes suggests that the alpha and beta nucleotide phosphates are as important as the gamma phosphate in binding to the enzyme. A stable pyruvate carboxylase chromium nucleotide complex was not observed. These results are quite different from those found with yeast hexokinase where a stable complex between CrATP, sugar, and enzyme is found and hexokinase appears to be specific toward the beta, gamma phosphates of its nucleotide substrates.
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PMID:Rat liver pyruvate carboxylase. Inhibition by chromium nucleotide complexes. 124 76

RINm5F insulinoma cells show a defective physiological insulin secretory response to glucose stimulation. The short chain carbonic acid sodium butyrate induced a growth arrest during a 72-h tissue culture period. In contrast to control RINm5F cells, 2 mM glucose increased insulin secretion by more than 70% in these sodium butyrate-treated cells (1 mM) without any further increase of the secretory rate between 2 and 20 mM glucose. This effect of sodium butyrate on insulin secretion was assessed in comparison with its effect on gene expression of the GLUT1 and GLUT2 glucose transporter, hexokinase type I and type II, glucokinase and insulin. Sodium butyrate at a 1 mM concentration decreased GLUT1 gene expression by nearly 50%, but did not induce gene expression of the low-affinity GLUT2 glucose transporter above the detection limit. Furthermore, sodium butyrate increased glucokinase gene expression by more than 50% and hexokinase type II gene expression by more than 100%, while insulin gene expression was increased only by 24%. Hexokinase type II enzyme activity was increased by more than 100% without a concomitant significant change of the glucokinase enzyme activity. Sodium butyrate (2 mM) caused effects comparable with those of 1 mM sodium butyrate. Thus the improved insulin secretory responsiveness of RINm5F insulinoma cells after sodium butyrate treatment at low non-physiological millimolar glucose concentrations can be interpreted as a result of an increased hexokinase-mediated metabolic flux rate through the glycolytic chain.
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PMID:Effects of sodium butyrate on glucose transporter and glucose-phosphorylating enzyme gene expression in RINm5F insulinoma cells. 886 83