The enzyme, characterized from the bacterium Thauera aromatica, participates in an anaerobic phenol degradation pathway. It catalyses the para dephosphorylation and carboxylation of phenylphosphate to 4-hydroxybenzoate. The enzyme from Thauera aromatica consists of four different subunits and requires K+ and a divalent metal cation (Mg2+ or Mn2+) for activity. It is strongly inhibited by oxygen.
The expected taxonomic range for this enzyme is: Thauera aromatica
The enzyme, characterized from the bacterium Thauera aromatica, participates in an anaerobic phenol degradation pathway. It catalyses the para dephosphorylation and carboxylation of phenylphosphate to 4-hydroxybenzoate. The enzyme from Thauera aromatica consists of four different subunits and requires K+ and a divalent metal cation (Mg2+ or Mn2+) for activity. It is strongly inhibited by oxygen.
Substrates: the enzyme also catalyzes the exchange of free CO2 with the carboxyl group of 4-hydroxybenzoate. The 14CO2 exchange reaction catalyzed by the three subunits of the core enzyme (54, 53, and 10 kDa) requires the fully reversible release of CO2 from 4-hydroxybenzoate with formation of a tightly enzyme-bound phenolate intermediate. Carboxylation of phenylphosphate requires in addition the 18-kDa subunit, which is thought to form the same enzyme-bound energized phenolate intermediate from phenylphosphate with virtually irreversible release of phosphate Products: -
Substrates: the enzyme also catalyzes the exchange of free CO2 with the carboxyl group of 4-hydroxybenzoate. The 14CO2 exchange reaction catalyzed by the three subunits of the core enzyme (54, 53, and 10 kDa) requires the fully reversible release of CO2 from 4-hydroxybenzoate with formation of a tightly enzyme-bound phenolate intermediate. Carboxylation of phenylphosphate requires in addition the 18-kDa subunit, which is thought to form the same enzyme-bound energized phenolate intermediate from phenylphosphate with virtually irreversible release of phosphate Products: -
enzyme preparation containing 6 M enzyme is completely inactivated by 0.1 mM dithionite, and the half-life was less than 1 min. Both the net carboxylation and isotope exchange activities are affected in the same way
the enzyme is strongly inhibited by oxygen. The enzyme is inactivated in a stoichiometric way, and the half-life was less than 1 min. The phenylphosphate carboxylation and the CO2 exchange activities are equally affected
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