Protein
Ketol-acid reductoisomerase (NADP(+)) 2
Organism
Bacillus cereus (strain ATCC 14579 / DSM 31 / JCM 2152 / NBRC 15305 / NCIMB 9373 / NRRL B-3711)
Function
Involved in the biosynthesis of branched-chain amino acids (BCAA). Catalyzes an alkyl-migration followed by a ketol-acid reduction of (S)-2-acetolactate (S2AL) to yield (R)-2,3-dihydroxy-isovalerate. In the isomerase reaction, S2AL is rearranged via a Mg-dependent methyl migration to produce 3-hydroxy-3-methyl-2-ketobutyrate (HMKB). In the reductase reaction, this 2-ketoacid undergoes a metal-dependent reduction by NADPH to yield (R)-2,3-dihydroxy-isovalerate.
Similarity
Belongs to the ketol-acid reductoisomerase family.
Sequence
MKTYYEKDANVELLQGKTVAVVGYGSQGHAQAQNLRDSGVEVVVGVRPGKSYEVAKADGFEVMSVSEAVRTAQVVQMLLPDEQQAHVYKAEVEENLREGQMLLFSHGFNIHFGQINPPSYVDVAMVAPKSPGHLVRRVFQEGNGVPALVAVHQDATGTALHVALAYAKGVGCTRAGVIETTFQEETETDLFGEQAVLCGGVTALVKAGFETLTEGGYRPEIAYFECLHELKLIVDLMYEGGLTTMRHSISDTAEFGDYVTGSRIVTDETKKEMKRVLTEIQQGEFAKKWILENQAGRPTYNAMKKAEQNHQLEKVGAELREMMSWIHAPKELVKK