Novel non-heme iron center of nitrile hydratase with a claw setting of oxygen atoms.
The iron-containing nitrile hydratase (NHase) is a photoreactive enzyme that is inactivated in the dark because of persistent association with NO and activated by photo-dissociation of NO. The crystal structure at 1.7 A resolution and mass spectrometry revealed the structure of the non-heme iron catalytic center in the nitrosylated state. Two Cys residues coordinated to the iron were post-translationally modified to Cys-sulfenic and -sulfinic acids. Together with another oxygen atom of the Ser ligand, these modifications induced a claw setting of oxygen atoms capturing an NO molecule. This unprecedented structure is likely to enable the photo-regulation of NHase and will provide an excellent model for designing photo-controllable chelate complexes and, ultimately, proteins.
Nagashima
S
S
Nakasako
M
M
Dohmae
N
N
Tsujimura
M
M
Takio
K
K
Odaka
M
M
Yohda
M
M
Kamiya
N
N
Endo
I
I
D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D006836:Hydro-Lyases / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D008958:Models, Molecular; D019159:Nonheme Iron Proteins / Q000737:chemistry* / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry*; D011487:Protein Conformation; D011499:Protein Processing, Post-Translational
D001426:Bacterial Proteins; D019159:Nonheme Iron Proteins; D006836:Hydro-Lyases; C048831:nitrile hydratase; D010100:Oxygen