Isoleucine trans

Conversion of the acetohydroxy acids to the a,/3-dihydroxyacid precursors of valine and isoleucine is catalyzed by acetohydroxy acid isomeroreductase. The a,/3-dihydroxy acids are both converted to the a-keto acid precursors of valine and isoleucine by a dihydroxy acid dehydrase. Finally, the two amino acids are formed in trans-... 

Human urine Cardiovascular risk 4680 1H NMR Isoleucine Valine Methylguanidine Hippurate 2-Hydroxibutirate Succine Scyllo-inositol Trans-aconitate Proline betaine (21)... 

Ala = Alanine, 6-Br-Trp = 6-bromotryptophan, Dide-Phe = a,P-dide-hydro-3,4,5-trihydroxyphenylalanine, Dide-Val = a,P-didehydro-valine, diOH-Sty = 3,4-dihydroxy-trans-styrylamine = [( )-l-amino-2-(3,4-dih-ydroxyphenyl)ethene], Gly = Glycine, lieu = Isoleucine, Leu = Leucine, N-Me = A-methyl, N,N-diMe = A,A-dimethyl-, P-OH = P-hydroxy, OH-Sty = 4-hydroxy-tra s-styrylamine = [( )-l-amino-2-(4-hydroxypheny-l)ethene], Phe = Phenylalanine, Phe-Et = Phenylethylamine, Pro= Proline, Sty = Styrylamine, Trp = Tryptophan, Tyr = Tyrosine, Val = Valine. 

Davies, N. M. and D. H. G. Crout, Pyrrolizidine alkaloid biosynthesis. Relative rates of incorporation of the isomers of isoleucine into the necic acid component of senecionine, J. Chem. Soc., Perkin Trans. I, 2079-2086 (1974). 

Crout DHG, Whitehouse D (1977) Absolute ctmliguration of 2,3-dihydroxy-3-methypentanoic acid, an intermediate in the biosynthesis of isoleucine, and its identity with the esterifying acid of the pyrrolizidine alkaloid strigosine. J Chem Soc, Perkin Trans I 544—549... 

Cahill R, Crout DHG, Gregorio MVM, Mitchell MB, Miiller US (1983) Pyrrolizidine alkaloid biosynthesis stereochemistry of the formation of isoleucine in senecio species and of its conversion into necic acid. J Chem Soc, Perkin Trans 1173-180... 

Witten et al. (1973) identified adipic and 3-methyladipic acids and also reported the presence in urine, using GC-MS, of aconitic and isocitric acids in addition to citrate. Mamer et al, (1971) reported the occurrence of several hydroxyaliphatic acids in addition to those already identified by other workers, and Mamer and Tjoa have identified 2-ethylhydracrylic acid in urine derived from isoleucine metabolism (Mamer and Tjoa, 1974). Urine from healthy children and adults may contain low amounts of aliphatic dicarboxylic acids of chain length C4-C8 (Lawson et ai, 1976). Pettersen and Stokke (1973) reported a series of 3-methyl-branched C4-C8 dicarboxylic acids in urine from normal subjects, and Lindstedt and co-workers have identified other dicarboxylic acids with cyclopropane rings and acetylenic bonds as well as a series of cis and trans mono-unsaturated aliphatic dicarboxylic acids (Lindstedt et al., 1974,1976 Lindstedt and Steen, 1975). 

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