The effect of bacterial glutathione S-transferase on morpholine degradation

Glutathione S-transferases (GSTs) constitute a large family of enzymes that catalyze the addition of glutathione to endogenous, or xenobiotic, often toxic electrophilic compounds. The effect of this enzyme in facilitating polychlorinated biphenyls degradation has been studied previously. Here the effects of induced cell-free extracts of Acinetobacter calcoaceticus and Pseudomonas aeruginosa (grown on hexadecane), and E. coli BL21 (induced with pGEX-2T plasmid on isothiopropylgalactoside) were recruited to facilitate morpholine degradation by Mycobacterium and were compared with non-induced strains. The results showed that all induced strains had significantly more GST activity compared to non-induced ones, and the strain with most GST activity, A. calcoaceticus BS, removed morpholine faster. Eukaryotic GST gene expressed in E. coli BL21 also could facilitate morpholine degradation by Mycobacterium, The same experiments performed with cell-free extracts of non-induced cells did not show any significant effects on morpholine removal. These results showed that there is a correlation between GST activity and acceleration of morpholine degradation.