Class I histone deacetylase AcuC (Acetoin utilization protein)-like enzymes
AcuC (Acetoin utilization protein) is a class I deacetylase found only in bacteria and is involved in post-translational control of the acetyl-coenzyme A synthetase (AcsA). Deacetylase AcuC works in coordination with deacetylase SrtN (class III), possibly to maintain AcsA in active (deacetylated) form and let the cell grow under low concentration of acetate. B. subtilis AcuC is a member of operon acuABC; this operon is repressed by the presence of glucose and does not show induction by acetoin; acetoin is a bacterial fermentation product that can be converted to acetate via the butanediol cycle in absence of other carbon sources. Inactivation of AcuC leads to slower growth and lower cell yield under low-acetate conditions in Bacillus subtilis. In general, Class I histone deacetylases (HDACs) are Zn-dependent enzymes that catalyze hydrolysis of N(6)-acetyl-lysine residues in histone amino termini to yield a deacetylated histone (EC 3.5.1.98). Enzymes belonging to this group participate in regulation of a number of processes through protein (mostly different histones) modification (deacetylation). Class I histone deacetylases in general act via the formation of large multiprotein complexes. Members of this class are involved in cell cycle regulation, DNA damage response, embryonic development, cytokine signaling important for immune response and in posttranslational control of the acetyl coenzyme A synthetase.
Comment:Active site includes Zn binding site, lipophilic tube and foot pocket.
Comment:Active site consists of a long narrow tunnel (that apparently serves for substrate binding) and a cavity with Zn ion (that is important for catalysis). In this structure, the tunnel is filled by the aliphatic chain of the inhibitor.
Structure:1C3R: Aquifex aeolicus histone deacetylase homolog binds trichostatin A inhibitor; contacts at 4.0A.