| Title : Display of a novel carboxylesterase CarCby on Escherichia coli cell surface for carbaryl pesticide bioremediation - Liu_2022_Microb.Cell.Fact_21_97 |
| Author(s) : Liu Y , Wang X , Nong S , Bai Z , Han N , Wu Q , Huang Z , Ding J |
| Ref : Microb Cell Fact , 21 :97 , 2022 |
| Abstract : BACKGROUND: Carbamate pesticides have been widely used in agricultural and forestry pest control. The large-scale use of carbamates has caused severe toxicity in various systems because of their toxic environmental residues. Carbaryl is a representative carbamate pesticide and hydrolase/carboxylesterase is the initial and critical enzyme for its degradation. Whole-cell biocatalysts have become a powerful tool for environmental bioremediation. Here, a whole cell biocatalyst was constructed by displaying a novel carboxylesterase/hydrolase on the surface of Escherichia coli cells for carbaryl bioremediation. RESULTS: The carCby gene, encoding a protein with carbaryl hydrolysis activity was cloned and characterized. Subsequently, CarCby was displayed on the outer membrane of E. coli BL21(DE3) cells using the N-terminus of ice nucleation protein as an anchor. The surface localization of CarCby was confirmed by SDS-PAGE and fluorescence microscopy. The optimal temperature and pH of the engineered E. coli cells were 30 degreesC and 7.5, respectively, using pNPC4 as a substrate. The whole cell biocatalyst exhibited better stability and maintained approximately 8-fold higher specific enzymatic activity than purified CarCby when incubated at 30 degreesC for 120 h. In addition, ~ 100% and 50% of the original activity was retained when incubated with the whole cell biocatalyst at 4 degC and 30 degreesC for 35 days, respectively. However, the purified CarCby lost almost 100% of its activity when incubated at 30 degreesC for 134 h or 37 degreesC for 96 h, respectively. Finally, approximately 30 mg/L of carbaryl was hydrolyzed by 200 U of the engineered E. coli cells in 12 h. CONCLUSIONS: Here, a carbaryl hydrolase-containing surface-displayed system was first constructed, and the whole cell biocatalyst displayed better stability and maintained its catalytic activity. This surface-displayed strategy provides a new solution for the cost-efficient bioremediation of carbaryl and could also have the potential to be used to treat other carbamates in environmental bioremediation. |
| ESTHER : Liu_2022_Microb.Cell.Fact_21_97 |
| PubMedSearch : Liu_2022_Microb.Cell.Fact_21_97 |
| PubMedID: 35643494 |
| Gene_locus related to this paper: baca2-a7z924 |
| Gene_locus related to this paper: baca2-a7z924 |
Liu Y, Wang X, Nong S, Bai Z, Han N, Wu Q, Huang Z, Ding J (2022)
Display of a novel carboxylesterase CarCby on Escherichia coli cell surface for carbaryl pesticide bioremediation
Microb Cell Fact
21 :97
Liu Y, Wang X, Nong S, Bai Z, Han N, Wu Q, Huang Z, Ding J (2022)
Microb Cell Fact
21 :97