cd04907

Second of two tandem C-terminal ACT domains of threonine dehydratase I (ThrD-I; L-threonine hydrolyase); This CD includes the second of two tandem C-terminal ACT domains of threonine dehydratase I (ThrD-I; L-threonine hydrolyase) which catalyzes the committed step in branched chain amino acid biosynthesis in plants and microorganisms, the pyridoxal 5'-phosphate (PLP)-dependent dehydration/deamination of L-threonine (or L-serine) to 2-ketobutyrate (or pyruvate). ThrD-I is a cooperative, feedback-regulated (isoleucine and valine) allosteric enzyme that forms a tetramer and contains four pyridoxal phosphate moieties. Members of this CD belong to the superfamily of ACT regulatory domains.