InterPro domain: IPR016206

Ketol-acid reductoisomerases (KARI) catalyses two steps in the biosynthesis of branched-chain amino acids. The reaction involves an Mg2+ dependent alkyl migration followed by an NADPH-dependent reduction of the 2-keto group. There are two groups of KARI enzymes: class I is a short form found in fungi and most bacteria, and class II is a long form found in plants and certain bacteria (although their sequences differ) [ 1 , 2 ]. However, there has also been a long form found in certain bacteria, but these differ from class II sequences found in plants.

This group represents a ketol-acid reductoisomerase, plant type.

1. The crystal structure of a bacterial class II ketol-acid reductoisomerase: domain conservation and evolution. Protein Sci. 14, 3089-100
2. Facile crystallization of Escherichia coli ketol-acid reductoisomerase. Acta Crystallogr. D Biol. Crystallogr. 60, 1432-4