In-situ monitoring of xenobiotics using genetically engineered whole-cell-based microbial biosensors: recent advances and outlook

Abstract

Industrialisation, directly or indirectly, exposes humans to various xenobiotics. The increased magnitude of chemical pesticides and toxic heavy metals in the environment, as well as their intrusion into the food chain, seriously threatens human health. Therefore, the surveillance of xenobiotics is crucial for social safety and security. Online investigation by traditional methods is not su cient for the detection and identi cation of such compounds because of the high costs and their complexity. Advancement in the eld of genetic engineering provides a potential opportunity to use genetically modi ed microorganisms. In this regard, whole-cell-based microbial biosensors (WCBMB) represent an essential tool that couples genetically engineered organisms with an operator/promoter derived from a heavy metal-resistant operon combined with a regulatory protein in the gene circuit. The plasmid controls the expression of the reporter gene, such as gfp, luc, lux and lacZ, to an inducible gene promoter and has been widely applied to assay toxicity and bioavailability. This review summarises the recent trends in the development and application of microbial biosensors and the use of mobile genes for biomedical and environmental safety concerns.

Use of whole-cell bioreporters to assess bioavailability of contaminants in aquatic systems

“…The bacterium E. coli has been widely used as a host cell for WCB to measure the genotoxicity of typical environmental contaminants such as inorganic and organic compounds (Yoon et al, 2016;Ali et al, 2021). However, in addition to E. coli, other Gram-negative bacteria such as Alcaligenes eutrophus (Peitzsch et al, 1998;Leth et al, 2002) and Cupriavidus metallidurans (Magrisso et al, 2009) as well as Gram-positive bacteria such as Bacillus subtilis and Staphylococcus aureus (Tauriainen et al, 1998;Bondarenko et al, 2008) have also been widely used for the construction of WCBs.…”

Mark‐recapture of microorganisms

“…It is possible to engineer barcodes to differ from one another by manipulating the barcode length, nucleotide composition, and/or genomic location. In experiments that use multiple markers, minimizing sequence similarity among barcodes can improve barcode assignment accuracy as de novo mutations and sequencing errors can change nucleotide composition of the barcode (Ali et al, 2021; Buschmann, 2017). Marking does not influence an individual's performance .…”

Immobilized Enzyme-based Novel Biosensing System for Recognition of Toxic Elements in the Aqueous Environment

“…The biosensors employ a biological recognition element (bioreceptor), can be a whole cell-base system or cell partbased system, for the detection of toxic pollutants, these devices allow onside quantification and avoid the requirement of sophisticated equipment [31]. The development of a wide type of biosensors using different bioreceptors such as microbial fuel cells [18,[32][33][34][35][36], microorganisms (Whole cell-based) [37][38][39][40], antibodies [41][42][43], enzymes [44][45][46][47][48][49][50], among others has been reported in the literature. On the other hand, biosensors can be placed as a favorable alternative due to the variability of pollutants (Heavy metals, organic compounds, drugs, and microorganisms) that are capable of pollutant trace detection [29].…”