Whole-cell bioreporters for evaluating petroleum hydrocarbon contamination

Abstract

Whole-cell bioreporter (WCB) is a category of biological analytical tools using living microorganisms to sense chemicals by producing quantifiable signals. Comparing to conventional chemical analysis, WCBs have the features of rapidness, cost-effectiveness and easy operation. This paper critically reviews the concept and recent progress in constructing and applying WCBs for sensing petroleum hydrocarbons, including n-alkanes and aromatic hydrocarbons. Additionally, some WCBs can evaluate the toxicity of petroleum hydrocarbons, linking their natural occurrence to ecological risks. Further discussions address the state-of-art design of WCBs for petroleum hydrocarbons, comprehensively assessing the key challenges in improving their sensitivity and limit of detection, including host strains, reporter genes and regulatory systems. Regarding the significant gaps between laboratory trials and real-world scenarios, we also discuss some restriction factors influencing bioreporter performance in sensing petroleum hydrocarbons in environmental samples, e.g., low solubility, and suggest some solutions as biosurfactant and chemotaxis. Further development of sensing devices and multisensing WCBs can provide more feasibilities overcoming the applicable barriers. This review comprehensively summarizes the current progress of WCBs for petroleum hydrocarbons, and raises new insights into their bright future in practices of environmental monitoring and risk assessment.