On the mechanisms of the formation of L-alloisoleucine and the 2-hydroxy-3-methylvaleric acid stereoisomers from L-isoleucine in maple syrup urine disease patients and in normal humans.

@article{Mamer1992OnTM,
  title={On the mechanisms of the formation of L-alloisoleucine and the 2-hydroxy-3-methylvaleric acid stereoisomers from L-isoleucine in maple syrup urine disease patients and in normal humans.},
  author={Orval A. Mamer and Mark L. J. Reimer},
  journal={The Journal of biological chemistry},
  year={1992},
  volume={267 31},
  pages={
          22141-7
        }
}
  • O. Mamer, M. L. Reimer
  • Published 5 November 1992
  • Medicine, Chemistry
  • The Journal of biological chemistry
2-Keto-3-methylvaleric acid (KMVA) has been found not to undergo spontaneous keto-enol tautomerization in neutral aqueous solution, alone or in the presence of large concentrations of pyridoxamine or pyridoxamine-5-phosphate. This finding denies the commonly held suppositions that 3R-KMVA is derived spontaneously from 3S-KMVA in vivo, and that L-alloisoleucine is the product of the reamination of this 3R-KMVA. Evidence presented here suggests that racemization of the 3-carbon of L-isoleucine… Expand
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