Thermostable N-carbamoyl-D-amino acid amidohydrolase: screening, purification and characterization.

摘要: Abstract A thermostable N- carbamoyl- d -amino acid amidohydrolase was found in the cells of newly isolated bacterium, Blastobacter sp. A17p-4. The bacterium also showed -specific hydantoinase activity. activity exhibited a temperature optimum at 50–55°C, and stable up to 50°C. A17p-4 purified homogeneity characterized. It has relative molecular weight about 120 000 consists three identical subunits with 40 000. Carbamoyl- acids having hydrophobic groups served as good substrates for enzyme. been suggested that production from dl -5-substituted hydantoin involves action series enzymes involved pyrimidine degradation, namely amide-ring opening enzyme, dihydropyrimidinase, N-carbamoylamide hydrolyzing β-ureidopropionase. However, enzyme did not hydrolyze β-ureidopropionate; suggesting coexisting hydantoinase, probably is different