G-site residue S67 is involved in the fungicide-degrading activity of a tau class glutathione S-transferase from Carica papaya.

ABSTRACT: Thiram is a toxic fungicide extensively used for the management of pathogens in fruits. Although it is known that thiram degrades in plant tissues, the key enzymes involved in this process remain unexplored. In this study, we report that a tau class glutathione S-transferase (GST) from Carica papaya can degrade thiram. This enzyme was easily obtained by heterologous expression in Escherichia coli, showed low promiscuity toward other thiuram disulfides, and catalyzed thiram degradation under physiological reaction conditions. Site-directed mutagenesis indicated that G-site residue S67 shows a key influence for the enzymatic activity toward thiram, while mutation of residue S13, which reduced the GSH oxidase activity, did not significantly affect the thiram-degrading activity. The formation

SUBMITTER: Wang SY 

PROVIDER: S-EPMC10958117 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature