Heterologous Expression and Characterization of A Novel Ochratoxin A Degrading Enzyme, N-acyl-L-amino Acid Amidohydrolase, from .

Ochratoxin A (OTA) is a well-known, natural contaminant in foods and feeds because of its toxic effects, such as nephrotoxicity in various animals. Recent studies have revealed that could generate enzymes to efficiently degrade OTA to ochratoxin α (OTα) in vitro. In an effort to obtain the OTA degrading mechanism, we purified and identified a novel degrading enzyme, N-acyl-L-amino acid amidohydrolase (OTase), from DSM 16503 via mass spectrometry. The same gene of the enzyme was also encountered in other strains. OTase belongs to peptidase family M20 and contains metal ions at the active site. In this study, recombination OTase was expressed and characterized in . The molecular mass of recombinant rOTase was approximately 47.0 kDa, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited a wide temperature range (30-70 °C) and pH adaptation (4.5-9.0) and the optimal temperature and pH were 50 °C and 6.5, respectively.