Molecular Docking and In Vitro Studies of Ochratoxin A (OTA) Biodetoxification Testing Three Endopeptidases

• Published in: Molecules (Basel, Switzerland) Vol. 28; no. 5; p. 2019
• Main Authors: Orozco-Cortés, Pablo César, Flores-Ortíz, Cesar Mateo, Hernández-Portilla, Luis Barbo, Vázquez Medrano, Josefina, Rodríguez-Peña, Olga Nelly
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 21.02.2023; MDPI
• Subjects: Ananas comosus bromelain cysteine-protease; Animal Feed - analysis; Animals; Bacillus subtilis neutral metalloendopeptidase; Binding sites; biodetoxification; Book publishing; bovine trypsin serine-protease; Bromelains; Cattle; Chemical reactions; Cysteine; degradability; Economic impact; Enzymes; Feed industry; Food; Health problems; Hydrogen bonds; Instrument industry; Intestine; Ligands; Metabolites; Metalloendopeptidases; Molecular docking; Molecular Docking Simulation; Mycotoxins; Ochratoxin A; Ochratoxins - analysis; Peptides; Protease; Proteases; Proteins; Reaction mechanisms; Toxins; Trypsin; α–ochratoxin; United States; α–ochratoxin; mycotoxin detoxifier; biodetoxification; bovine trypsin serine-protease; degradability; Ananas comosus bromelain cysteine-protease; Bacillus subtilis neutral metalloendopeptidase; enzymatic mycotoxin detoxification
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules28052019

Ochratoxin A (OTA) is considered one of the main mycotoxins responsible for health problems and considerable economic losses in the feed industry. The aim was to study OTA's detoxifying potential of commercial protease enzymes: (i) bromelain cysteine-protease, (ii) bovine trypsin serine-protease and (iii) neutral metalloendopeptidase. In silico studies were performed with reference ligands and T-2 toxin as control, and in vitro experiments. In silico study results showed that tested toxins interacted near the catalytic triad, similar to how the reference ligands behave in all tested proteases. Likewise, based on the proximity of the amino acids in the most stable poses, the chemical reaction mechanisms for the transformation of OTA were proposed. In vitro experiments showed that while bromelain reduced OTA's concentration in 7.64% at pH 4.6; trypsin at 10.69% and the neutral metalloendopeptidase in 8.2%, 14.44%, 45.26% at pH 4.6, 5 and 7, respectively ( < 0.05). The less harmful α-ochratoxin was confirmed with trypsin and the metalloendopeptidase. This study is the first attempt to demonstrate that: (i) bromelain and trypsin can hydrolyse OTA in acidic pH conditions with low efficiency and (ii) the metalloendopeptidase was an effective OTA bio-detoxifier. This study confirmed α-ochratoxin as a final product of the enzymatic reactions in real-time practical information on OTA degradation rate, since in vitro experiments simulated the time that food spends in poultry intestines, as well as their natural pH and temperature conditions.