Function
Serine acetyltransferase (SAT) catalyzes the reaction converting serine to O-acetyl-serine using acetyl-CoA as a cofactor. This reaction is the first step in the synthesis of cysteine in bacteria and plants[1]. SAT is regulated by a feedback inhibition by ots end product - cysteine.
Structural highlights
The structure of the complex of SAT with its substrate serine suggest that His169 and Asp154 form a catalytic dyad and that His189 may stabilize the oxyanion intermediate. Glu177 helps to position Arg203 and His204 for serine binding. Arg 253 is important for the catalytic efficiency of SAT. Lys230 is required for the cofactor acetyl-CoA binding[2].
