Carboligase activity of α-ketoglutarate dehydrogenase

Schlossberg, Michael A.; Bloom, Robert J.; Richert, Dan A.; Westerfeld, W. W.

doi:10.1021/bi00807a015

Cited by 34 publications

(22 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The carboligase reaction is in fact cata lyzed by the decarboxylase component of the a-ketoglutarate dehydrogenase complex [11][12][13], an enzyme that requires the cofactor TPP for activity. Thus, thiamine deficiency, which does depress a-ketoglutarate dehydro genase activities [14,15], is postulated to result in decreased catabolism via the carbo ligase pathway and hence accumulation of glyoxylate.…”

mentioning

confidence: 99%

Thiamine Deficiency and Glyoxylic Acid

Stewart¹,

Grammer²,

Brosemer³

1981

Ann Nutr Metab

View full text Add to dashboard Cite

The effect of thiamine deficiency on glyoxylic acid metabolism in mice and rats was investigated to determine whether the vitamin deficiency results in gross effects on glyoxylate levels via an alteration in the activity of α-ketoglutarate:glyoxylate carboligase. Thia-mine-deprived or pyrithiamine-treated mice did not show a decreased oxidation of [1-¹⁴C]glyoxylate to respiratory CO₂; there was some decrease in the conversion of [2-¹⁴C]glyoxylate into CO₂ by pyrithiamine-treated mice, but not by thiamine-deprived animals. Dietary thiamine deprivation caused a decrease in carboligase levels in liver but no effect on levels in three brain regions. Pyrithiamine treatment had no significant effect on liver carboligase activities, but did decrease the levels in cerebrum, cerebellum and brainstem. Thiamine-deprived and pyrithiamine-treated mice showed decreased urinary glycolic acid excretion. Glyoxylic acid excretion by thiamine-deprived rats was monitored in order to re-examine a previous report by another laboratory that glyoxyluria occurs under these conditions. Trace amounts of glyoxylate could be detected in the urine of rats fed thiamine-deficient diet for 3–5 weeks, but urinary glyoxylate was not detectable at later stages of thiamine deprivation. These results do not support a significant role for α-ketoglutarate:carboligase activity in the primary etiology of thiamine deficiency syndromes.

show abstract

mentioning

confidence: 99%

Thiamine Deficiency and Glyoxylic Acid

Stewart¹,

Grammer²,

Brosemer³

1981

Ann Nutr Metab

View full text Add to dashboard Cite

show abstract

“…Glyoxylic acid is a reactive compound and is rapidly con verted to CO2 in the liver and kidney mito chondria by TPP-depcndent a-KG:GA carboligase [18], as well as via the glyoxylate oxidation cycle [19], It is also converted to oxalate by GAO and LDH or it may be reduced to glycolate, which is further con verted to oxalate by GAD ( fig. 3).…”

Section: Discussionmentioning

confidence: 99%

“…The decarbox ylation of glyoxylate by a-KG:GA carboligase was also significantly decreased in both liver and kidney mitochondria. The carboligase activity is associated with the a-ketoglutarate-decarboxylase moiety of a-ketoglutarate-dehydrogenase complex [18] and thia- All values are mean ± SEM o f 6 rats. ** p < 0.01; *** p < 0.001, as compared to PFC rats.…”

Section: Discussionmentioning

confidence: 99%

Oxalate Metabolism in Thiamine-Deficient Rats

et al. 1987

View full text Add to dashboard Cite

Male weanling rats were maintained on a thiamine-deficient diet for 4 weeks, and compared with ad libitum and pair-fed controls. Thiamine deficiency led to slow growth and finally a decrease in body weight. Liver and kidney weights of the deficient rats were low, but appropriate to the body weight. Thiamine deficiency also caused a significant decrease in erythrocyte transketolase levels. The decarboxylation of glyoxylate both via the glyoxylate oxidation cycle and α-ketoglutarate:glyoxylate (α-KG:GA) carboligase was significantly lower in the liver and kidney mitochondria, leading to accumulation of glyoxylate in the tissues and its excretion in the urine. Part of the accumulated glyoxylate is converted to oxalate, causing hyperoxaluria.

show abstract

“…Bourke et al (1972) also demonstrated the presence of mitochondrial and soluble CL; however, neither were reduced in primary hyperoxaluria type 1 patients. Schlossberg et al (1970) found that all the CL activity in rat liver, heart and brain and rabbit liver was particulate, only muscle having significant soluble activity. In addition, it was shown that CL co-purified with the first decarboxylating component of the mitochondrial matrix enzyme 2-oxog!utarate dehydrogenase.…”

Section: Transaminationmentioning

confidence: 94%

Recent advances in the understanding, diagnosis and treatment of primary hyperoxaluria type 1

Danpure

1989

J of Inher Metab Disea

View full text Add to dashboard Cite

Carboligase activity of α-ketoglutarate dehydrogenase

Cited by 34 publications

References 15 publications

Thiamine Deficiency and Glyoxylic Acid

Thiamine Deficiency and Glyoxylic Acid

Oxalate Metabolism in Thiamine-Deficient Rats

Recent advances in the understanding, diagnosis and treatment of primary hyperoxaluria type 1

Contact Info

Product

Resources

About