Valine metabolism

H. E. Umbarger and B. Brown, Isoleucine and valine metabolism in Escherichia coli. VIII. The formation of acetolactate. J. Biol. Chem. 233, 1156 1160 (1958). 

Roe CR, Cederbaum SD, Roe DS, Mardach R, Galindo A, Sweetman L. Isolated isobutyryl-CoA dehydrogenase deficiency an unrecognized defect in human valine metabolism. Mol Genet Metab. 1998 Dec 65(4) 264-71. PubMed citation... 

Isolated isobutyryl-CoA dehydrogenase deficiency an unrecognized defect in human valine metabolism. 

C-11) Hypervalinemia. There is a suspected defect in valine transaminase, which acts at one of the steps in valine metabolism. 

Propionyl-CoA carboxlase (methionine, leucine and valine metabolism) Biotin is found in numerous foods and also is synthesized by intestinal bacteria and as such deficiencies ofj he vitamin are rare. 

B2. Bamabei, O., Valyasevi, A., Bamess, L. A., and Gyorgy, P., Sources of methyl-malonate in rat urine valine metabolism. Arch. Biochem. Biophys. 69, 259 (1957). 

Isoluecine catabolism. The catabolism of leucine is presented as a representative of branched-chain amino acid (leucine, isoleucine, and valine) metabolism. This can occur in more than one tissue (see text for more detail). The purple lettering under an enzyme indicates the resulting disease when this enzyme is missing. 

Ikeda, Y. Tanaka, K. (1983) J. Biol. Chem. 258, 9477-9487. Purification and characterization of 2-methyl-branched chain acylcoenzyme A dehydrogenase, an enzyme involved in the isoleucine and valine metabolism, from rat liver mitochondria. 

Knerr I, Vockley J, Gibson KM. Disorders of leucine, isoleucine and valine metabolism. In Physician s guide to the diagnosis, treatment and follow-up of... 

Chen X, Nielsen KF, Borodina I, Kielland-Brandt MC, Karhumaa K. (2011). Increased isobutanol production in Saccharomyces cerevisiae by overexpression of genes in valine metabolism. Biotechnol Biofuels, 4, 21. 

Carbon-13 labelling has been utilised in studies of valine metabolism. [3- C]-Valine was administered to fasted rats and the glycogen formed was isolated degradation confirmed the formation of a 3-carbon intermediate [175], A patient with methylmalonic acidemia has been studied by administration of [2- CJvaline and [2,3- C]valine methylmalonic acid was isolated from the urine and analysed by C-NMR [176,177]. 

The disorders of isoleucine and valine metabolism are detected in a sequential process that begins with the evaluation of the symptoms and signs displayed by the patient. Clinical chemistry is helpful in the assessment of ketogenesis by urinary tests for ketones or quantification of 3-hydroxybuty-rate and acetoacetate in the blood. The electrolytes and pH may provide evidence of acidosis and it is important to assess the presence or absence of hyperammonemia. Amino acid analysis of the plasma and urine may be helpful. In virtually all instances the definitive diagnosis will come from organic acid analysis of the urine. 

Andresen, B. S., Christensen, E., Corydon, T. J. et al. (2000) Isolated 2-methylbutyryl-glycinuria caused by short/branched-chain acyl-CoA dehydrogenase deficiency Identification of a new enzyme defect, resolution of its molecular basis, and evidence for distinct acyl-CoA dehydrogenases in isoleucine and valine metabolism. Am. J. Hum. Genet,67, 1095. 

Brown, G.K., Hunt, S.M. Scholem, R., Fowler, K., Grimes, A., Mercer, J.F.B., Truscott, R.M., Cotton, R.G.H., Rogers, J.G. and Banks, D.M. (1982) Beta-hydroxyisobutyryl coenzyme A deacylase deficiency a defect in valine metabolism associated with physical malformations. Pediatr. 70, 532-538. 

The a-ketobutyrate is decarboxylated to valine and follows the pattern of valine metabolism discussed previously (see Section V). 

Tanaka, K., Armitage, I.M., Ramsdell, H.S., Hsia, Y.E., Lipsky, S.R. and Rosenberg, L.E. (1975), [ C]-Valine metabolism in methylmalonic aciduria using nuclear magnetic resonance Propionate as an obligate intermediate. Proc. Natl. Acad. Sci. U.S.A.,12,3692. 

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