Detoxification of ochratoxin A by Lysobacter sp. CW239 and characteristics of a novel degrading gene carboxypeptidase cp4. (March 2020)

• Record Type: Journal Article
• Authors: Wei, Wei; Qian, Yingying; Wu, Yanbo; Chen, Ying; Peng, Cheng; Luo, Mingzhong; Xu, Junfeng; Zhou, Yu
• Is Part Of: Environmental pollution. Volume 258(2020)
• Publication Date: 2020-03
• Subjects: Ochratoxin A -- Carboxypeptidase -- Gene cloning -- Overexpression -- Biodegradation; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2019.113677
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Ochratoxin A (OTA) is a potent mycotoxin that frequently contaminates agro-products and threatens food safety. A highly efficient OTA degrading strain Lysobacter sp. CW239 was isolated, and the OTA degradation characteristics were investigated. A novel OTA degrading gene carboxypeptidase cp4 was successfully cloned and characterized from CW239. The heterologous recombinant was constructed by gene cp4 and expression vector pET-32a (+) and overexpressed by E. coli BL21 CodonPlus™ (DE3). The recombinant protein rCP4 was purified, and the OTA-degrading activity was evaluated. Although OTA was efficiently degraded by CW239 (24-h degradation ratio of 86.2%), the 24-h OTA degradation ratio for rCP4 was only 36.8% at fairly high concentration (0.25 mg/mL) protein. The degraded product was obtained by immune affinity column (IAC) and determined by mass spectrometry (MS), and the degraded product was the less toxic ochratoxin α (OTα). Based on the serial investigations of this study, OTA might be simultaneously co-degraded by CP4 and another unknown degrading agent in that degrading strain. Graphical abstract: Image 1 Highlights: Ochratoxin A was efficiently degraded by the newly isolated Lysobacter sp. CW239. A novel detoxification gene carboxypeptidase cp4 was cloned and characterized. The ochratoxin A degraded product was the less toxic ochratoxin α. Abstract : The characteristics of the strain CW239 and detoxify enzyme in study suggested the potential significance of further OTA detoxification development.