Figure 4.

Diagram illustrating the secondary structure elements of the thioredoxin-like domain (Trx) found in GSTs. α-Helices are shown as yellow blocks, while β-strands are shown as green arrows. Each element is numbered for reference in the text. The Trx domain is extended in GSTs at the C-terminal end, which continues to complete the overall GST structure. The sulfhydryl group of glutathione (GSH) is displayed as a yellow ball, and key interactions between GSH and residues from the Trx domain are shown as dashed blue lines. Amino acid positions of interest are shown in red type and correspond to the red boxes in the alignment in Figure 3.