Fig. 1: Structural analysis of CxxC/S- and CGFS-type glutaredoxins.
From: Molecular basis for the distinct functions of redox-active and FeS-transfering glutaredoxins
a Primary structure comparison of glutaredoxins from both classes around the active site: CxxC/S-type: Homo sapiens (Hs) Grx1 (gene glrx1, PDB 1B4Q), Arabidopsis thaliana (At) GrxC5 (gene GrxC5, PDB 3RHB), and Hs Grx2 (GLRX2, PDB 2HT9). CGFS-type: Hs Grx5 (GLRX5, PDB 2WUL) and Escherichia coli (Ec) Grx4 (grxD, PDB 1YKA). The alignment was generated by super-positioning of the 3D structures of the PDB entries. The critical lysyl residue is highlighted in red, the yellow box the class-specific loops, the active sites are shown in blue and brown according to the class. b Surface representation of one monomer of the human Grx2 holo-complex with bound GSH and Fe2S2 cluster (PDB 2HT9). c Surface representation of one monomer of the human Grx5 holo-complex with bound GSH and Fe2S2 cluster (PDB 2WUL). d Super-positioning of the structures of the CxxC/S-type human Grx2 (blue) and the CGFS-type human Grx5 (brown) including their bound FeS clusters and glutathione. e Comparison of the structures of all CxxC/S-type (blue) and CGFS-type (gray) Grxs with non-covalently bound GSH (PDB entries used: CGFS-type Grxs, 2XCI, 2WUL, 3RHC, and 5J3R; CxxC/S-type Grxs, 1B4Q, 2E7P, and 2HT9). f Comparison of the critical lysyl residue in all structures of CGFS-type Grxs (PDB entries: 2LKU, 2MNZ, 2WCI, 2WUL, 2YAN, 3GX8, 2IPZ, and 2ZYW). g Position of the phenylalanyl and tyrosyl residues in CGFS- (brown) and CxxC/S-type (blue) Grxs in relation to the GSH thiol (PDB entries used: CGFS-type Grxs, 2WUL and 3RHC; CxxC/S-type Grxs, 1B4Q, 2E7P, and 2HT9.
