Degradation of Aflatoxin B1 by recombinant laccase extracellular produced from Escherichia coli.
Ecotoxicol Environ Saf
; 244: 114062, 2022 Oct 01.
Article
in En
| MEDLINE
| ID: mdl-36108433
ABSTRACT
Bioenzymatic degradation of aflatoxin B1 (AFB1) is a safe, efficient and environmentally friendly detoxification technology. In this work, AFB1 was successfully degraded by recombinant laccase (fmb-rL103) in the absence of a mediator. The laccase gene was cloned from Bacillus vallismortis fmb-103, and was expressed in heterologous host Escherichia coli after codon optimization. The extracellular production of fmb-rL103 could be induced by adding methanol (6 %, v/v), and the maximum yield was 1545.6 U/L. In the 10 L bioreactor, the extracellular yield increased to 50,950.6 U/L after 20 h of induction, accounting for three quarters of the total yield. The mechanism of methanol-induced extracellular secretion was further studied by measuring acetate content, lac103 gene expression and cell membrane permeability. Furthermore, we explored the biochemical properties of fmb-rL103 and its degradation conditions on AFB1. The degradation efficiency increased constantly with increase in incubation pH and temperature, and exceeded 60 % at pH 7.0 and 37 °C. This work provides new insight into developing the large-scale production of laccase and its application to degrade AFB1.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Aflatoxin B1
/
Laccase
Language:
En
Journal:
Ecotoxicol Environ Saf
Year:
2022
Document type:
Article