1h75
STRUCTURAL BASIS FOR THE THIOREDOXIN-LIKE ACTIVITY PROFILE OF THE GLUTAREDOXIN-LIKE PROTEIN NRDH-REDOXIN FROM ESCHERICHIA COLI.
OverviewOverview
NrdH-redoxin is a representative of a class of small redox proteins that contain a conserved CXXC motif and are characterized by a glutaredoxin-like amino acid sequence and thioredoxin-like activity profile. The crystal structure of recombinant Escherichia coli NrdH-redoxin in the oxidized state has been determined at 1.7 A resolution by multiwavelength anomalous diffraction. NrdH-redoxin belongs to the thioredoxin superfamily and is structurally most similar to E. coli glutaredoxin 3 and phage T4 glutaredoxin. The angle between the C-terminal helix alpha3 and strand beta4, which differs between thioredoxin and glutaredoxin, has an intermediate value in NrdH-redoxin. The orientation of this helix is to a large extent determined by an extended hydrogen-bond network involving the highly conserved sequence motif (61)WSGFRP(D/E)(67), which is unique to this subclass of the thioredoxin superfamily. Residues that bind glutathione in glutaredoxins are in general not conserved in NrdH-redoxin, and no glutathione-binding cleft is present. Instead, NrdH-redoxin contains a wide hydrophobic pocket at the surface, similar to thioredoxin. Modeling studies suggest that NrdH-redoxin can interact with E. coli thioredoxin reductase at this pocket and also via a loop that is complementary to a crevice in the reductase in a similar manner as observed in the E. coli thioredoxin-thioredoxin reductase complex.
About this StructureAbout this Structure
1H75 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
ReferenceReference
Structural basis for the thioredoxin-like activity profile of the glutaredoxin-like NrdH-redoxin from Escherichia coli., Stehr M, Schneider G, Aslund F, Holmgren A, Lindqvist Y, J Biol Chem. 2001 Sep 21;276(38):35836-41. Epub 2001 Jul 5. PMID:11441020 Page seeded by OCA on Fri May 2 18:31:21 2008