EC Number   |
Substrates |
Organism |
Products |
Reversibility |
|---|
  3.1.2.29 | acetyl-CoA + H2O |
- |
Streptomyces cattleya |
acetate + CoA |
- |
? |
| 3.1.2.29 | acetyl-CoA + H2O |
poor substrate |
Streptomyces cattleya |
acetate + CoA |
- |
? |
| 3.1.2.29 | fluoroacetyl-CoA + H2O |
- |
Streptomyces cattleya |
fluoroacetate + CoA |
- |
? |
| 3.1.2.29 | fluoroacetyl-CoA + H2O |
- |
Dichapetalum cymosum |
fluoroacetate + CoA |
- |
? |
| 3.1.2.29 | fluoroacetyl-CoA + H2O |
does not accept acetyl-CoA as a substrate |
Streptomyces cattleya |
fluoroacetate + CoA |
- |
? |
| 3.1.2.29 | fluoroacetyl-CoA + H2O |
the enzyme is strongly selective for fluoroacetyl-CoA compared with acetyl-CoA |
Streptomyces cattleya |
fluoroacetate + CoA |
- |
? |
| 3.1.2.29 | more |
no substrate: acetyl-CoA |
Dichapetalum cymosum |
? |
- |
? |
| 3.1.2.29 | more |
Thr 42, Glu 50, and His 76 are key catalytic residues. FlK minimizes interaction with the thioester carbonyl, leading to selection against acetyl-CoA binding. Fluorinated substrates bind in a hydrophobic binding pocket created by a lid structure, containing Val 23, Leu 26, Phe 33, and Phe 36, that is not found in other structurally characterized members of this superfamily. Water plays a critical role in fluorine specificity. The Phe 36 gate residue functions to exclude water from the active site |
Streptomyces cattleya |
? |
- |
? |
| 3.1.2.29 | more |
chemical, kinetic, and structural mechanism for the selectivity for fluoroacetyl-CoA. Following substrate binding, fluoroacetyl-CoA reacts with Glu50 to acylate this side chain. After enzyme acylation, a proton is abstracted by His 76 to generate an enolate that can break down through a proposed ketene intermediate. The pro-R proton of fluoroacetyl-CoA is specifically abstracted. The selectivity for the fluoroacetyl-CoA substrate appears to rely not only on the enhanced polarization provided by the electronegative fluorine substitution but also on molecular recognition of fluorine in both formation and breakdown of the acyl-enzyme intermediate to control active site reactivity |
Streptomyces cattleya |
? |
- |
? |
| 3.1.2.29 | more |
the high selectivity of fluoroacetyl-CoA thioesterase is achieved through catalysis rather than molecular recognition. Deprotonation at the Calpha position to form a putative ketene intermediate only occurs on the fluorinated substrate, thereby accelerating the rate of hydrolysis 10000fold compared with the nonfluorinated congene. An enzyme-anhydride intermediate is formed for the nonfluorinated substrate |
Streptomyces cattleya |
? |
- |
? |
