Pyruvate carboxylase lipoic acid

The coenzyme form of pantothenic acid is coenzyme A and is represented as CoASH. The thiol group acts as a carrier of acyl group. It is an important coenzyme involved in fatty acid oxidation, pyruvate oxidation and is also biosynthesis of terpenes. The epsilon amino group of lysine in carboxylase enzymes combines with the carboxyl carrier protein (BCCP or biocytin) and serve as an intermediate carrier of C02. Acetyl CoA pyruvate and propionyl carboxylayse require the participation of BCCP. The coenzyme form of folic acid is tetrahydro folic acid. It is associated with one carbon metabolism. The oxidised and reduced forms of lipoic acid function as coenzyme in pyruvate and a-ketoglutarate dehydrogenase complexes. The 5-deoxy adenosyl and methyl cobalamins function as coenzyme forms of vitamin B12. Methyl cobalamin is involved in the conversion of homocysteine to methionine. 

The -amino groups of lysyl residues serve as attachment sites of a number of coenzymes in proteins (e.g. biotin in pyruvate carboxylase, pyridoxal phosphate in phosphorylase, lipoic acid in lipoate acetyl-transferase) and form covalent intermediates in several enzymic reactions (e.g. transaldolase, aldolase, etc.). Discussion of all of these naturally-occuring derivatives of lysine will not be attempted in this treatise, but the investigator using chemical modification of proteins should be aware of their possible presence and effect on the results of his experiments. It should be noted that e-N-phospholysine has been reported in nucleoside diphosphate kinase (Walinder 1968). 

Lipoic acid 3-10 mg Lactic and pyruvic acidemia" Pyruvate carboxylase... 

The results of the resolution and reconstitution experiments carried out with the E. coli pyruvate dehydrogenation complex indicate that there are specific binding sites on the lipoic reductase-transacetylase component for the carboxylase and the flavoprotein. In other words, the latter two enzymes appear to be specifically oriented with respect to the lipoic acid bound to the lipoic reductase-transacetylase component. It is evident from the re-... 

At autopsy, multiple areas of necrosis are found in the grey matter of the central part of the brain and in the spinal cord [141]. Leigh compared these changes to Wernicke s encephalopathy, though with a different distribution. This suggested either thiamine deficiency or inability to utilize thiamine normally, but treatment with thiamine or thiamine pyrophosphate has no effect on the course of the disease [142]. Lipoic acid, like thiamine pyrophosphate involved in the oxidative decarboxylation of pyruvic acid, has been given to some patients [137] the concentration of pyruvic acid in the blood fell and clinical improvement was claimed. Others have tried lipoic acid treatment with less success—the pyruvic acid content of the blood fell, but there was no effect on the clinical course of the disease [136]. It is now known that the enzymes dec2irboxylating pyruvic acid are normal and that the metabolic error results from a lack of pyruvate carboxylase. 

Maesaka, H., Kamiya, K., Misugi, K. and Tada, K. (1976), Hyperalaninemia, hyper-pyruvicemia, and lactic acidosis due to pyruvate carboxylase deficiency of liver. Treatment with thiamine and lipoic acid. Eur. J. Pediatr., 122,159. 

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