2,3-Dihydroxy-3-methylpentanoic acid is an intermediate in the metabolism of
isoleucine
Isoleucine (symbol Ile or I) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH form under biological conditions), an α-carboxylic acid group (which is in the depr ...
.
Metabolism
2,3-Dihydroxy-3-methylpentanoate is synthesized by the action of
acetolactate mutase with subsequent reduction from
α-aceto-α-hydroxybutyrate through
3-hydroxy-2-keto-3-methylpentanoate:
: α-aceto-α-hydroxybutyrate → 3-hydroxy-2-keto-3-methylpentanoate
: 3-hydroxy-2-keto-3-methylpentanoate + NAD(P)H → 2,3-dihydroxy-3-methylpentanoate + NAD(P)
+
It is then processed by the action of
dihydroxyacid dehydratase
The enzyme dihydroxy-acid dehydratase () catalyzes the chemical reaction
:2,3-dihydroxy-3-methylbutanoate \rightleftharpoons 3-methyl-2-oxobutanoate + H2O
This enzyme participates in valine, leucine and isoleucine biosynthesis and pantothenate ...
, which results in
2-keto-3-methylvalerate and water:
: 2,3-dihydroxy-3-methylpentanoate → 2-keto-3-methylvalerate + H
2O
Transamination
Transamination is a chemical reaction that transfers an amino group to a ketoacid to form new amino acids. This pathway is responsible for the deamination of most amino acids. This is one of the major degradation pathways which convert essential ...
of 2-keto-3-methylvalerate yields isoleucine.
References
{{DEFAULTSORT:Dihydroxy-3-methylpentanoic acid, 2,3-
Alpha hydroxy acids
Vicinal diols
Beta hydroxy acids