Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Reductive, nonreductive, and photolytic interactions of vanadate with fructose-1,6-bisphosphate aldolase were examined and used to explore the interactions of oxoanions with aldolase. Aldolase is known to interact strongly with oxoanions at low ionic strength and weakly at higher ionic strength. Oxoanions inhibit aldolase competitively with respect to fructose 1,6-bisphosphate although the location of the oxoanion binding site on aldolase remains elusive. In this work, the interaction of aldolase with a series of oxoanions was compared at ionic strength approaching physiologic levels. The size and shape of the anion were important for the effective binding to aldolase, and no significant increase in affinity for aldolase was observed by the addition of alkyl groups to the oxoanions. Vanadate competitively inhibits aldolase in a manner analogous to the other oxoanions. Since vanadate solutions contain a mixture of vanadate oxoanions, the nature of the inhibition was determined using a combination of enzyme kinetics and 51V NMR spectroscopy. Aldolase contains a significant number of thiol functionalities, and as expected, vanadate undergoes redox chemistry with them, generating an irreversibly inhibited aldolase. This oxidative chemistry was attributed to the vanadate tetramer, whereas vanadate dimer was a reversible inhibitor. Vanadate monomer does not significantly interact with aldolase reversibly or irreversibly. Vanadyl cation has the lowest inhibition constant under these high ionic strength conditions. Using Yonetani-Theorell analysis, it appears that phosphate, pyrophosphate, and sulfate bind to the same site on aldolase, whereas vanadate, arsenate, and molybdate bind to another site. UV light-induced photocleavage of aldolase by vanadate was examined, and the loss of aldolase activity was correlated with cleavage of the aldolase subunit. Further studies using vanadium as a probe should reveal details on the location of the vanadate and vanadyl cation binding sites. This study suggests several sites on aldolase will accommodate oxoanions, and one of these sites also accommodates vanadyl cation.
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PMID:Interaction of rabbit muscle aldolase at high ionic strengths with vanadate and other oxoanions. 163 17

The effects of vanadate, an oxidized form of vanadium, on glucose metabolism of the lens in diabetic rats were studied. Five-week-old male Sprague-Dawley rats were rendered diabetic with intraperitoneal injection of streptozotocin (50 mg/kg). One week later, the diabetic rats were given 0.2 g/l NaVO3 -5g/l NaCl solution in drinking water ad libitum for 2 weeks and biochemical parameters in their lenses were determined. Blood glucose levels significantly decreased in the vanadate-administered diabetic rats (DV group), compared with the diabetic rats given no vanadate (D group). In the DV group, a significant decrease was observed in lens fructose content compared with the D group. Lens ketohexokinase activity tended to be higher and lens aldolase activity was significantly higher in the DV group than in the D group. These results indicate that vanadate accelerates the metabolic reaction from sorbitol pathway to glycolysis.
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PMID:[Effects of vanadate on glucose metabolism in the lens of rats with streptozotocin-induced diabetes--ketohexokinase and aldolase activity]. 788 27