Spectral and Photochemical Properties of Rhodobacter sphaeroides R-26 Reaction Center Films in Vacuum.
A A Zabelin1, V A Shkuropatova2, V A Shuvalov2
1Institute of Basic Biological Problems, Pushchino Scientific Center for Biological Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia. zabelin.bio@gmail.com.
Biochemistry. Biokhimiia
|November 7, 2019
Summary
The detergent n-dodecyl-β-D-maltoside (DM) best stabilizes bacterial reaction centers (RCs) in vacuum-dried films, preserving spectral and photochemical properties for potential use in photoconverting systems.
Area of Science:
- Biophysics
- Photochemistry
- Materials Science
Background:
- Reaction centers (RCs) from Rhodobacter sphaeroides R-26 are crucial for photosynthesis.
- Stabilizing RCs in a dehydrated state is essential for developing artificial photosynthetic systems.
Purpose of the Study:
- To investigate the impact of vacuum dehydration on the spectral and photochemical properties of bacterial RCs.
- To evaluate the efficacy of different detergents (LDAO, TX100, DM) in stabilizing RC-detergent complexes under vacuum.
Main Methods:
- Absorption spectroscopy in visible/near-IR and mid-IR regions.
- Preparation of vacuum-dried RC films on inorganic supports (quartz, CaF2).
- Analysis of spectral shifts, protein structure (α-helix content), and photochemical activity.
Main Results:
- n-dodecyl-β-D-maltoside (DM) effectively minimized irreversible changes in RCs during vacuum dehydration.
- RC-DM films showed a slight increase in α-helices, reversible spectral shifts, and retained photochemical activity.
- LDAO caused RC destruction in vacuum, while TX100 offered moderate stabilization.
Conclusions:
- Detergent-protein interactions and micelle properties are key to maintaining RC structure during vacuum dehydration.
- DM is the most suitable detergent for preparing stable, photoactive RC films for hybrid photoconverting systems.
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