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Published on: July 17, 2020
Alternative Complex III from phototrophic bacteria and its electron acceptor auracyanin
Erica L W Majumder1, Jeremy D King, Robert E Blankenship
1Washington University in St. Louis, Departments of Biology and Chemistry, Campus Box 1137, One Brookings Dr, St. Louis, MO 63130, USA.
Biochimica Et Biophysica Acta
|January 30, 2013
Summary
Alternative Complex III (ACIII) is a bacterial electron transfer complex replacing cytochrome bc1. It utilizes menaquinone and auracyanin for energy conservation in phototrophic bacteria.
Area of Science:
- Biochemistry
- Microbiology
- Photosynthesis
Background:
- Alternative Complex III (ACIII) is a novel electron transfer complex.
- It is functionally analogous to bacterial cytochrome bc1 or b6f complexes.
- ACIII is found in diverse phototrophic and nonphototrophic bacteria.
Purpose of the Study:
- To review recent work on ACIII and auracyanin.
- To focus on photosynthetic systems and electron transfer mechanisms.
- To highlight ACIII's role in energy conservation.
Main Methods:
- Structural and functional analysis of ACIII.
- Investigation of bacterial enzyme families.
- Review of literature on ACIII and auracyanin.
Main Results:
- ACIII exhibits menaquinone: electron acceptor oxidoreductase activity.
- The complex contains subunits with Fe-S centers and c-type hemes.
- In phototrophs, auracyanin serves as the electron acceptor instead of soluble cytochrome.
Conclusions:
- ACIII complexes represent a unique system for photosynthetic electron transfer.
- ACIII is crucial for energy conservation in certain bacterial systems.
- The complex's structure and function are linked to bacterial evolution and adaptation.
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