Microbial functionalities and immobilization of environmental lead: Biogeochemical and molecular mechanisms and implications for bioremediation

• Published in: Journal of hazardous materials 2023-09, Vol.457, p.131738-131738, Article 131738
• Main Authors: Elizabeth George, S., Wan, Yongshan
• Format: Article
• Language: English
• Subjects: Biodegradation, Environmental; Heavy metals; Humans; Lead; Metals, Heavy - metabolism; Microbial induced carbonate precipitation; Microbial remediation; Phosphate solubilizing bacteria; Phosphates; Soil; Soil Microbiology; Soil Pollutants - metabolism; Sulfate reducing microorganism
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2023.131738

The increasing environmental and human health concerns about lead in the environment have stimulated scientists to search for microbial processes as innovative bioremediation strategies for a suite of different contaminated media. In this paper, we provide a compressive synthesis of existing research on microbial mediated biogeochemical processes that transform lead into recalcitrant precipitates of phosphate, sulfide, and carbonate, in a genetic, metabolic, and systematics context as they relate to application in both laboratory and field immobilization of environmental lead. Specifically, we focus on microbial functionalities of phosphate solubilization, sulfate reduction, and carbonate synthesis related to their respective mechanisms that immobilize lead through biomineralization and biosorption. The contributions of specific microbes, both single isolates or consortia, to actual or potential applications in environmental remediation are discussed. While many of the approaches are successful under carefully controlled laboratory conditions, field application requires optimization for a host of variables, including microbial competitiveness, soil physical and chemical parameters, metal concentrations, and co-contaminants. This review challenges the reader to consider bioremediation approaches that maximize microbial competitiveness, metabolism, and the associated molecular mechanisms for future engineering applications. Ultimately, we outline important research directions to bridge future scientific research activities with practical applications for bioremediation of lead and other toxic metals in environmental systems. [Display omitted] •Microorganisms mediate biomineralization and biosorption of Pb in the environment.•Tolerance of Pb toxicity is critical to selection of phosphate solubilizing bacteria.•Sulfate reduction functional genes may serve as environmental genetic markers.•Biogenesis of carbonate involves ureolytic organisms in alkaline environments.•Optimization of microbe functionalities is key to real world applications.