Patulin Detoxification by Evolutionarily Divergent Reductases of ATCC 621.

The mycotoxin patulin in processed apple juice poses a significant threat to food safety, driving the need for effective detoxification strategies. ATCC 621 can detoxify patulin to ascladiol using either the short-chain dehydrogenases/reductases (SDRs)─GOX0525, GOX1899, and GOX0716─or the aldo-keto reductase (AKR) GOX1462. While GOX0525 and GOX1899 have been previously characterized, this study focuses on GOX0716 and GOX1462, evaluating their optimal pH, thermostability, thermoactivity, and substrate specificity, thereby completing the characterization of all four reductases.

Unveiling the Broad Substrate Specificity of Deoxynivalenol Oxidation Enzyme DepA and Its Role in Detoxifying Trichothecene Mycotoxins.

DepA, a pyrroloquinoline quinone (PQQ)-dependent enzyme isolated from mutans 17-2-E-8, exhibits versatility in oxidizing deoxynivalenol (DON) and its derivatives. This study explored DepA's substrate specificity and enzyme kinetics, focusing on DON and 15-acetyl-DON. Besides efficiently oxidizing DON, DepA also transforms 15-acetyl-DON into 15-acetyl-3-keto-DON, as identified via LC-MS/MS and NMR analysis.

Microbial detoxification of mycotoxins in food.

Mycotoxins are toxic secondary metabolites produced by certain genera of fungi including but not limited to , and . Their persistence in agricultural commodities poses a significant food safety issue owing to their carcinogenic, teratogenic, and immunosuppressive effects. Due to their inherent stability, mycotoxin levels in contaminated food often exceed the prescribed regulatory thresholds posing a risk to both humans and livestock.

Characterization of Two Dehydrogenases from Involved in the Transformation of Patulin to Ascladiol.

Patulin is a mycotoxin that primarily contaminate apples and apple products. Whole cell or cell-free extracts of ATCC 621 were able to transform patulin to E-ascladiol. Proteins from cell-free extracts were separated by anion exchange chromatography and fractions with patulin transformation activity were subjected to peptide mass fingerprinting, enabling the identification of two NADPH dependent short chain dehydrogenases, GOX0525 and GOX1899, with the requisite activity.