an acyl phosphate + H2O = a carboxylate + H(+) + phosphate Optimum pH is 5.2-6.5. Thermostable. Retains 85-90 % of its activity after 3 hours of incubation at 90 degrees Celsius. Has a considerably reduced catalytic efficiency compared to other mesophilic acylphosphatases. Shows a considerable resistance against urea denaturation since the full enzymatic activity is maintained in the presence of urea concentrations approaching 6.0 M and that only a slight decreae of 10-15 % was observed with higher urea concentrations. Belongs to the acylphosphatase family.