Langmuir-Blodgett monolayer films of the Rhodopseudomonas viridis reaction center: determination of the order of the hemes in the cytochrome c subunit.
The Langmuir-Blodgett (LB) film technique has been applied to produce oriented and photo-active films of isolated reaction center cytochrome c complexes (RC-cyt c) and chromatophore membranes from the photosynthetic bacterium Rhodopseudomonas viridis. Linear dichroism (LD) and redox potentiometry have been used to identify the four cytochrome c hemes of the RC-cyt c complex. Resolved angular orientations of the four hemes in LB films of both isolated RC-cyt-c complexes and of chromatophore membranes permit the reduction of the 24 possible arrangements to two. Additional structural and functional information from other sources allows us to propose a model which best accounts for all the available experimental data.
Alegria
G
G
Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia 19104.
Dutton
P L
PL
D003574:Cytochrome c Group / Q000737:chemistry*; D006418:Heme / Q000737:chemistry*; D010084:Oxidation-Reduction; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*; D012241:Rhodopseudomonas / Q000378:metabolism*; D013057:Spectrum Analysis
D003574:Cytochrome c Group; D045322:Photosynthetic Reaction Center Complex Proteins; D006418:Heme