FEATURES

FAMILY

DESCRIPTION

Also known as TDCB_SALTY, tdcB. Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2-ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA. TdcB also dehydrates serine to yield pyruvate via analogous enamine/imine intermediates. In the native structure, TdcB is in a dimeric form, whereas in the TdcB-AMP complex, it exists in a tetrameric form (dimer of dimers).

EXTERNAL LINKS

tdcB

Mutations

Mutation(s) distribution

Mutations table