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The reaction centre from green sulphur bacteria: progress towards structural elucidation
Hervé-W Rémigy1, Günter Hauska, Shirley A Müller
1Division of Biochemistry, Department of Chemistry, University of Crete, P.O. Box 1470, 71409, Heraclion, Greece, tsiotis@chemistry.uoc.gr.
Photosynthesis Research
|October 18, 2005
Summary
Green sulphur bacteria possess a unique FeS-type reaction centre (RC). This study reviews electron microscopy techniques and recent advances in determining the structure of these bacterial RCs.
Area of Science:
- Biochemistry
- Microbiology
- Structural Biology
Background:
- The reaction centre (RC) in green sulphur bacteria is an FeS-type RC.
- This type of RC is also found in Photosystem I (PS I) and heliobacteria.
- Green sulphur bacterial and heliobacterial RCs have homodimeric core domains, unlike purple bacteria, PS I, and Photosystem II (PS II).
Purpose of the Study:
- To describe electron microscopy and image processing techniques applicable to protein structure investigation.
- To review recent structural findings on the green sulphur bacterial RC.
Main Methods:
- Electron microscopy
- Image processing
- Scanning transmission electron microscopy (STEM)
Main Results:
- Recent advances have significantly improved the understanding of green sulphur bacterial RC structure.
- STEM has been pivotal in these structural studies.
Conclusions:
- Electron microscopy and image processing are crucial for elucidating the structure of FeS-type reaction centres.
- The homodimeric nature of green sulphur bacterial RCs distinguishes them from other photosynthetic systems.
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