Production of extracellular superoxide radical in microorganisms and its environmental implications: A review

Environ Pollut. 2023 Sep 15:122563. doi: 10.1016/j.envpol.2023.122563. Online ahead of print.ABSTRACTExtracellular superoxide radical (O2•-) is ubiquitous in microbial environments and has significant implications for pollutant transformation. Microbial extracellular O2•- can be produced through multiple pathways, including electron leakage from the respiratory electron transport chain (ETC), NADPH oxidation by the transmembrane NADPH oxidase (NOX), and extracellular reactions. Extracellular O2•- significantly influences the geochemical processes of various substances, including toxic metals and refractory organic pollutants. On one hand, extracellular O2•- can react with variable-valence metals and detoxify certain highly toxic metals, such as As(III), Cr(VI), and Hg(II). On the other hand, extracellular O2•- can directly or indirectly (via Bio-Fenton) degrade many organic pollutants, including a variety of emerging contaminants. In this work, we summarize the production mechanisms of microbial extracellular O2•-, review its roles in the transformation of environmental pollutants, and discuss the potential applications, limiting factors, and future research directions in this field.PMID:37717891 | DOI:10.1016/j.envpol.2023.122563
Source: Environmental Pollution - Category: Environmental Health Authors: Source Type: research