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Three-Dimensional Structure of Cytochrome c Nitrite Reductase As Determined by Cryo-Electron Microscopy
T N Baymukhametov1, Y M Chesnokov1, E B Pichkur1
1National Research Center «Kurchatov Institute», Akademika Kurchatova Sqr., 1, Moscow, 123182 , Russia.
Acta Naturae
|November 7, 2018
Summary
Researchers determined the structure of cytochrome c nitrite reductase from Thioalkalivibrio nitrativibrio using cryo-electron microscopy (cryo-EM). The resulting model aligns well with previous X-ray diffraction data.
Area of Science:
- Biochemistry
- Structural Biology
- Microbiology
Background:
- Cytochrome c nitrite reductase (Nrf) is crucial for microbial nitrogen cycling.
- Understanding Nrf structure provides insights into enzyme mechanisms and regulation.
Purpose of the Study:
- To determine the high-resolution structure of Thioalkalivibrio nitratireducens cytochrome c nitrite reductase.
- To assess potential structural heterogeneity of the enzyme using cryo-electron microscopy (cryo-EM).
Main Methods:
- Cryo-electron microscopy (cryo-EM) was employed to resolve the enzyme's structure.
- Analysis of the cryo-EM data yielded a model at 2.56 Å resolution.
Main Results:
- The three-dimensional structure of cytochrome c nitrite reductase was elucidated.
- Structural heterogeneity was investigated, revealing general similarity to existing X-ray diffraction models.
- Backbone and side-chain orientations were consistent between the cryo-EM and X-ray structures.
Conclusions:
- The cryo-EM structure provides a detailed view of cytochrome c nitrite reductase.
- The findings validate cryo-EM as a powerful tool for structural determination of microbial enzymes.
- The structural data can inform future studies on enzyme function and inhibition.
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