Excessive lead accumulation is a severe concern for the environment as its toxicity is associated with soil microbial diversity, agricultural production, and human health. Physico-chemical methods of remediation of lead from the existing environment are generally costly and also not efficient due to the production of another form of the toxic compound. Bioremediation has been now considered the most efficient method to remove heavy metals from the surrounding by using microorganisms and plants. Microbes are generally more resistant than any eukaryotic organism and act as a key player in mitigating lead toxicity. The absorption and accumulation of toxic metals by bacteria exhibit many metabolically related and independent processes. Biotransformation, biosorption, precipitation, and encapsulation are the most efficient strategies opted by the microbial system to remediate lead metal from wide sources such as soil, sludge, and wastewaters to clean the environment. Genetically improved bacterial strains have good efficiency and have multiple modes of remediation from soil and other industrial waste. However, environmental biotechnology has not yet explored many aspects of the interaction between metals and microorganisms, and further development and applications are needed to deliver the non-toxic form of lead into the ecosystem. This review also highlights the potential of lead-resistant bacteria used as a biosensor for lead contamination sites.
Key words: Lead toxicity, lead resistant bacteria, encapsulation, bacterial biosensors
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