2ZON: Crystal Structure Of Electron Transfer Complex Of Nitrite Reductase With Cytochrome C

Recent earth science studies have pointed out that massive acceleration of the global nitrogen cycle by anthropogenic addition of bio-available nitrogen has led to a host of environmental problems. Nitrous oxide (N(2)O) is a greenhouse gas that is an intermediate during the biological process known as denitrification. Copper-containing nitrite reductase (CuNIR) is a key enzyme in the process; it produces a precursor for N(2)O by catalysing the one-electron reduction of nitrite (NO2-) to nitric oxide (NO). The reduction step is performed by an efficient electron-transfer reaction with a redox-partner protein. However, details of the mechanism during the electron-transfer reaction are still unknown. Here we show the high-resolution crystal structure of the electron-transfer complex for CuNIR with its cognate cytochrome c as the electron donor. The hydrophobic electron-transfer path is formed at the docking interface by desolvation owing to close contact between the two proteins. Structural analysis of the interface highlights an essential role for the loop region with a hydrophobic patch for protein-protein recognition; it also shows how interface construction allows the variation in atomic components to achieve diverse biological electron transfers.
PDB ID: 2ZONDownload
MMDB ID: 73113
PDB Deposition Date: 2008/5/27
Updated in MMDB: 2009/11
Experimental Method:
x-ray diffraction
Resolution: 1.7  Å
Source Organism:
Similar Structures:
Biological Unit for 2ZON: tetrameric; determined by author and by software (PISA)
Molecular Components in 2ZON
Label Count Molecule
Proteins (4 molecules)
Dissimilatory Copper-containing Nitrite Reductase
Molecule annotation
Cytochrome C551
Molecule annotation
Chemicals (7 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB