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Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
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Structural basis of inter-protein electron transfer for nitrite reduction in denitrification
Masaki Nojiri1, Hiroyasu Koteishi, Takuya Nakagami
1Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. nojiri@ch.wani.osaka-u.ac.jp
Nature
|November 6, 2009
Summary
Researchers have elucidated the structure of a key protein complex involved in the nitrogen cycle. This finding reveals how electron transfer occurs between copper-containing nitrite reductase and its partner protein, crucial for regulating greenhouse gas emissions.
Area of Science:
- Biochemistry
- Environmental Science
- Structural Biology
Background:
- Anthropogenic activities have accelerated the global nitrogen cycle, leading to environmental issues.
- Nitrous oxide (N2O), a potent greenhouse gas, is produced during denitrification.
- Copper-containing nitrite reductase (CuNIR) is vital for N2O precursor formation.
Purpose of the Study:
- To investigate the unknown mechanism of electron transfer during denitrification.
- To determine the high-resolution crystal structure of the CuNIR-cytochrome c electron-transfer complex.
Main Methods:
- X-ray crystallography was employed to obtain the high-resolution structure.
- Analysis focused on the protein-protein interface and electron transfer pathway.
Main Results:
- The crystal structure of the electron-transfer complex between CuNIR and its cognate cytochrome c was determined.
- A hydrophobic electron-transfer path was identified at the protein-protein interface, facilitated by desolvation.
- A specific loop region with a hydrophobic patch was highlighted as essential for protein recognition.
Conclusions:
- The study reveals the structural basis of electron transfer between CuNIR and cytochrome c.
- Understanding this interface is key to comprehending biological electron transfer diversity.
- This knowledge contributes to understanding and potentially mitigating nitrogen cycle disruptions.
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