Cytosolic glutathione S-transferase in bacteria possesses the biochemical capacity to degrade various classes of organochlorine pollutants in the environment in addition to their primary role of defending the organism from a wide range of endobiotics and xenobiotic substrates. Furthermore, the ability of different classes of cGST to recognize a wide repertoire of substrates due the variability in the substrate binding site of the enzymes makes them well suited for bioremediation purposes. cGSTs act as dehalogenases promoting a rapid degradation of various organochlorine compounds. Dehalogenation served as the primary mechanism for detoxification of various organochlorine compounds, making them vulnerable to attack by other degradative enzymes. However, despite their potential and advantage of wide substrate specificity, cGSTs have not been exploited for bioremediation purposes. In this review, we described the various cGST classes in bacteria and their phylogenetic relationships. Furthermore, the review reiterated that cGSTs in bacteria are involved in dehalogenation reaction, and this property can be harnessed for bioremediation of a diverse class of organochlorine pollutants as they currently represent the largest class of pollutants in the environment.

Agricultural and industrial activities contribute most to the pollutants found globally; therefore, bioremediation of these pollutants is intensely sought. This research isolated a molybdenum-reducing bacterium from agricultural soil. The bacterium grown in low phosphate media (LPM) reduces molybadate to Mo-blue optimally at pH between 6.5 and 7.0, temperature between 35 and 40 °C, glucose at 5 g/L and glycine at 3 g/L were the best electron donor and nitrogen sources, respectively. The optimum molybdate concentration is between 80 and 100 mM, and phosphate concentration was between 5.0 and 7.5 mM. Phylogenetic analysis of 16S rRNA partial sequencing identified the bacterium as Enterobacter cloacae. The capacity of this bacterium to reduce toxic molybdenum to less toxic colloidal molybdenum blue is novel and form the basis for its use in future bioremediation of this pollutant.

Bioremediation of pollutants such as heavy metals is an economic and environmentally friendly process. A novel molybdenum-reducing bacterium was isolated and characterized for its potential to reduce hexavalent molybdenum to molybdenum blue (Mo-blue). The bacterium reduces molybdate optimally at pH between 6 and 8, temperature between 35 and 40 ËšC. Glucose was the best electron donor source supporting molybdate reduction followed by sucrose, fructose, starch and glycerol in descending order. Other requirements include optimum phosphate concentration at 5.0 mM and molybdate concentration between 20 and 40 mM. 16S rRNA partial sequencing and phylogenetic analysis identified the bacterium as Pantoea sp. strain HMY-P4. The capacity of this bacterium to reduce toxic soluble molybdenum to a less toxic form is novel and makes the bacterium an important instrument for bioremediation of this pollutant.

Pollution of the environment by heavy metals and other toxic xenobiotics has increasingly become global public health concern. Bacterial reduction of molybdenum to insoluble molybdenum blue (Mo-blue) forms the basis for its bioremediation. A bacterium with the ability to reduce toxic soluble molybdenum has been isolated from Agricultural soil and identified as Pseudomonas sp. based on the 16S rRNA partial sequencing and phylogenetic analysis. Spectroscopic analysis reveals that the bacterium reduced sodium molybdate to Mo-blue optimally at pH between 6.5 and 7.0, temperatures between 35 °C and 40 °C. Glucose was the best electron donor source supporting molybdate reduction, followed by sucrose, fructose, glycerol and starch in descending order. Other requirements include a phosphate concentration of 3.5 mM and a molybdate concentration of between 40 and 60 mM. The absorption spectrum of the Mo-blue produced was similar to the previously isolated Mo-reducing bacteria and closely resembles a reduced phosphomolybdate.

Tributyltin (TBT) is one of the most toxic substances ever deliberately introduced into the marine environment. The high toxicity of TBT has resulted in a wide range of adverse effects on biological systems ranging from bacteria to mammals and from the molecular to the community level. One of the most deleterious effects of TBT is imposex. The growth kinetics of TBT-Resistant Bacterium containing lead was studied. In this study various lead concentrations ranging from 1 to 100 mg/dm 3 were used. Seven kinetic models (Teissier, Monod, Yano, Luong, Aiba, Webb, and Haldane,) were investigated and the accuracy of the fitted models were evaluated using statistical analysis such as coefficient of determination, adjusted coefficient of determination (R 2 ) and root mean square (RMSE). Aiba model was fitted to the experimental growth kinetics data and gave a very good fit with an R 2 of 0.98 and RMSE of 0.0042 respectively. The calculated value for the Aiba constants such as maximal growth rate, half saturation constant and half inhibition constant rate symbolized by µ max , k s , and k i , were 0.