Glutaredoxin (GRX) family, GRX-like domain containing protein subfamily; composed of uncharacterized eukaryotic proteins containing a GRX-like domain having only one conserved cysteine, aligning to the C-terminal cysteine of the CXXC motif of GRXs. This subfamily is predominantly composed of plant proteins. GRX is a glutathione (GSH) dependent reductase, catalyzing the disulfide reduction of target proteins via a redox active CXXC motif using a similar dithiol mechanism employed by TRXs. GRX has preference for mixed GSH disulfide substrates, in which it uses a monothiol mechanism where only the N-terminal cysteine is required. Proteins containing only the C-terminal cysteine are generally redox inactive.
Comment: this only contains the C-terminal cysteine of the CXXC motif
Comment:GRX reduces protein disulfides via a dithiol mechanism similar to that employed by TRX, where the exposed N-terminal cysteine initiates attack on the substrate disulfide followed by an intramolecular attack of the the C-terminal cysteine. GRX also uniquely reduces GSH mixed disulfides in which it utilizes only the N-terminal cysteine in a monothiol mechanism.
Jiyao W et al.(2023). "The conserved domain database in 2023.",