FIGURE 1.4 Physiological responses responsible for imparting tolerance in nematodes to

polluted soils.

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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

GST has a wide range of activities, but its primary role is as a GSH

transferase, catalyzing the conjugation of electrophilic endobiotics and

xenobiotics (or their metabolites) to GSH (Li et al., 2012). GSTs also have

non-catalytic functions, such as serving as binding and carrier proteins, such

as ligands for certain hazardous chemicals. These processes are required for

cell survival and detoxification against reactive oxygen species (ROS) and

toxic electrophiles. Metallothioneins can operate as radical scavengers and

guard against metal toxicity by sequestering Zn, Cu, Cd, and Hg, among

other metals (Klaassen et al., 2019). If metabolization and excretion do not

keep up with intake rates, organic contaminants can build up in the tissue. In

Caenorhabditis elegans, Haitzer et al. (2000) discovered pyrene buildup in

lipid-rich body areas. Pollution avoidance, detoxification, and accumulation

(organic)/sequestration (heavy metals) are all accompanied by a variety of

more general strategies for surviving in stressful situations (Ekschmitt &

Korthals, 2006). These bioindicators’ responses to remediation tactics can

be used to examine how soil remediation approaches alter hazardous metal

bioavailability in the environment (Harrington et al., 2012).

1.7 CHALLENGES ASSOCIATED WITH MICROBE-ASSISTED

BIOREMEDIATION

Microbial degradation, in its broadest definition, refers to the employment

of microbes to break down, degrade, detoxify, or change contaminants in

the environment. Microbe-assisted bioremediation is unquestionably a

significantly more cost-effective and environmentally benign method of