Structural insights into the function of a thermostable copper-containing nitrite reductase
Fukuda, Y; Tse, KM; Lintuluoto, M; Fukunishi, Y; Mizohata, E; Matsumura, H; Takami, H; Nojiri, M; Inoue, T
HERO ID
2232089
Reference Type
Journal Article
Year
2014
Language
English
PMID
| HERO ID | 2232089 |
|---|---|
| In Press | No |
| Year | 2014 |
| Title | Structural insights into the function of a thermostable copper-containing nitrite reductase |
| Authors | Fukuda, Y; Tse, KM; Lintuluoto, M; Fukunishi, Y; Mizohata, E; Matsumura, H; Takami, H; Nojiri, M; Inoue, T |
| Journal | Journal of Biochemistry |
| Volume | 155 |
| Issue | 2 |
| Page Numbers | 123-135 |
| Abstract | Copper-containing nitrite reductase (CuNIR) catalyzes the reduction of nitrite (NO(-)2) to nitric oxide (NO) during denitrification. We determined the crystal structures of CuNIR from thermophilic gram-positive bacterium, Geobacillus thermodenitrificans (GtNIR) in chloride- and formate-bound forms of wild type at 1.15 Å resolution and the nitrite-bound form of the C135A mutant at 1.90 Å resolution. The structure of C135A with nitrite displays a unique η(1)-O coordination mode of nitrite at the catalytic copper site (T2Cu), which has never been observed at the T2Cu site in known wild-type CuNIRs, because the mobility of two residues essential to catalytic activity, Asp98 and His244, are sterically restricted in GtNIR by Phe109 on a characteristic loop structure that is found above Asp98 and by an unusually short CH-O hydrogen bond observed between His244 and water, respectively. A detailed comparison of the WT structure with the nitrite-bound C135A structure implies the replacement of hydrogen-bond networks around His244 and predicts the flow path of protons consumed by nitrite reduction. On the basis of these observations, the reaction mechanism of GtNIR through the η(1)-O coordination manner is proposed. |
| Doi | 10.1093/jb/mvt107 |
| Pmid | 24293549 |
| Wosid | WOS:000330895000007 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |
| Keyword | Metallo; Enzyme; Oxidation-Reduction; Enzyme; Copper; Metals; X-ray Crystallography; Methods; Thermostable enzyme |