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Expression, Solubilization, and Purification of Eukaryotic Borate Transporters
Published on: March 7, 2019
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A Sb(III)-specific efflux transporter from Ensifer adhaerens E-60
Ruixiang Yang1, Thiruselvam Viswanatham2, Shuangqin Huang1
1Institute of Environmental Microbiology, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Microbiological Research
|July 14, 2024
Summary
Researchers discovered AntB, a novel transporter in Ensifer adhaerens, that confers resistance to toxic antimony compounds. This finding enhances understanding of microbial antimony resistance and its role in the environment.
Area of Science:
- Environmental Microbiology
- Biochemistry
- Toxicology
Background:
- Antimony is a widespread environmental toxin.
- Microorganisms possess diverse mechanisms for antimony resistance, transformation, and extrusion.
- Efflux transporters play a crucial role in microbial detoxification.
Purpose of the Study:
- To identify and characterize novel genes conferring antimony resistance in Ensifer adhaerens.
- To elucidate the function of the identified transporter AntB and its regulatory mechanism.
- To understand the role of efflux transporters in the antimony biogeochemical cycle.
Main Methods:
- Identification of the AntB major facilitator superfamily (MFS) transporter on the Ensifer adhaerens E-60 chromosome.
- Analysis of the adjacent LysR-type transcriptional regulator LysRars.
- Heterologous expression of the antB gene in E. coli AW3110 (Δars).
- Assessing resistance to Sb(III) and Sb(V) and measuring intracellular antimony concentrations.
Main Results:
- The AntB transporter confers significant resistance to both Sb(III) and Sb(V).
- LysRars acts as an As(III)/Sb(III)-responsive transcriptional repressor regulating antB expression.
- Heterologous expression of antB in E. coli reduced intracellular Sb(III) levels, confirming its efflux function.
- Conserved cysteine residues were identified in both AntB and LysRars orthologs.
Conclusions:
- The discovery of AntB, an Sb(III) efflux transporter, expands the known mechanisms of microbial antimony resistance.
- The LysRars regulator provides insights into the transcriptional control of antimony resistance genes.
- This research contributes to understanding the microbial role in antimony cycling and detoxification in the environment.
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