Of hexose monophosphates

Both these compounds can also cause methemoglobin formation, stimulation of hexose monophosphate shunt activity in isolated suspensions of red cells, and reduced cell viability. 

Figure 21-9 Interrelationship of hexose monophosphate and glutathione pathways. GSH, Reduced glutathione GSSG, oxidized glutathione.

Studies at the U.S. Army Medical Research Institute of Chemical Defense are thus far consistent with the proposal that, with the exception of activation of hexose monophosphate shunt (Martens, 1994), this biochemical cascade may contribute to blister formation. In addition, however, the process would appear to require an active inflammatory response and altered fluid dynamics in the affected tissue to generate the very large blisters seen after sulfur mustard exposure. 

D8. Dumont, J. E., Stimulation in vitro of hexose monophosphate pathway in thyroid by iodothyrosines and Synkavit. Biochim. Biophys. Acta 60, 506-512 (1961). 

Sodium fluoroacetate is a controversial poison also known as Compound 1080. When an isolated rat heart is perfused with sodium fluoroacetate, the rate of glycolysis decreases and hexose monophosphates accumulate. In cardiac cells, fluoroacetate is condensed with oxaloacetate to give fluorocitrate. Under these conditions, cellular citrate concentrations increase, while the levels of other citric acid cycle components decrease. What enzyme is inhibited by fluorocitrate How can you account for the decrease in glycolysis and the buildup of hexose monophosphates ... 

The accumulation of citrate and the decrease in the levels of other citric acid cycle intermediates suggest that aconitase is inhibited by fluorocitrate. Excess citrate inhibits phosphofructokinase, causing a decrease in the rate of glycolysis and an accumulation of hexose monophosphates such as glucose 6-phosphate and fructose 1,6-bisphosphate. The controversy over Compound 1080 is between environmentalists, who want it banned from outdoor use, and farmers and ranchers, who find it useful against rodents and predators. Because of the way it acts on cells, there is no antidote and it produces a slow and painful death. 

Calvin cycle The cycle of photosynthetic dark reactions by which CO2 is fixed, reduced, and converted to glyceraldehydes-3-phosphate (the precursor of hexose monophosphates). 

Evidence from a number of sources indicated that pentose phosphates were metabolized in a series of reactions that resulted in the formation of hexose monophosphates and hexose diphosphates. Several enzyme steps are involved in these transformations. The reaction between D-ribulose 5-phosphate and D-ribose 5-phosphate to form D-sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate is catalyzed by an enzyme known as transketolase (91). This enzyme is found in plant, animal, and bacterial cells. Thiamine pyrophosphate (TPP) and Mg ions are required as cofactors. The mechanism of the reaction was suggested (92) as shown in reaction (28). 

Kaplan and Basford (1976) in their study of neutrophil function in four patients with megloblastic anemia showed that resting levels of hexose monophosphate shunt activities were slightly lower in PMN leukocytes from patients with vitamin Bi2 deficiency. However, when challenged with the latex beads or staphylococci, HMPS activity was only 1/3 that of controls. There was no impairment in leukocytes from patients with folic acid deficiency. Microbicidal activity was also slightly decreased in... 

Jensen, U.G., Brandt, N.J., Chistensen, E., Skovoby, R, Noigaard-Pedersen, B. and Simonsen, H., Neonatal screening for galactosemia by quantitative analysis of hexose monophosphates using tandem mass spectrometry A retrospective study. Clin. Chem., 47, 1364-1372 (2001). 

The rate of renewal of hexose monophosphate was found to be considerably lower than that of pyrophosphate or creatine phosphate (79,149). 

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