Mercury bioaccumulation and simultaneous nanoparticle synthesis by Enterobacter sp. cells

Area of Science:

• Environmental Microbiology
• Nanotechnology
• Bioremediation

Background:

• Mercury contamination poses significant environmental and health risks.
• Conventional mercury remediation methods often have limitations, such as mercury vaporization.
• There is a need for sustainable and efficient methods for mercury removal and valuable byproduct generation.

Purpose of the Study:

• To report a novel mercury-resistant Enterobacter sp. strain.
• To investigate the strain's ability for mercury bioaccumulation and simultaneous mercury nanoparticle synthesis.
• To characterize the synthesized mercury nanoparticles and assess their potential for environmental applications.

Main Methods:

• Isolation and characterization of a mercury-resistant Enterobacter sp. strain.
• Optimization of culture conditions (pH 8.0, low mercury concentration) for nanoparticle synthesis.
• Characterization of intracellular mercury nanoparticles using High-Resolution Transmission Electron Microscopy (HR-TEM), Energy Dispersive X-ray Analysis (EDX), Powder X-ray Diffraction (PXRD), and Atomic Force Microscopy (AFM).

Main Results:

• A mercury-resistant Enterobacter sp. strain was identified.
• The strain synthesized uniform, spherical, 2-5 nm intracellular mercury nanoparticles under optimized conditions.
• The mercury nanoparticles were recoverable and prevented mercury vaporization, addressing a key challenge in mercury remediation.
• Characterization confirmed the size, shape, and composition of the mercury nanoparticles.

Conclusions:

• The Enterobacter sp. strain demonstrates a unique capability for mercury bioaccumulation and simultaneous biosynthesis of mercury nanoparticles.
• This biological process offers a promising green alternative for mercury remediation from environmental effluents.
• The recoverable mercury nanoparticles can be utilized in various applications, contributing to sustainable nanotechnology.