Site-specific mutagenesis of the reaction centre from Rhodobacter sphaeroides studied by Fourier transform Raman spectroscopy: mutations at tyrosine M210 do not affect the electronic structure of the primary donor.
The effects of mutation of residue tyrosine M210 on the primary donor bacteriochlorophylls have been investigated by near infrared FT-Raman spectroscopy in reaction centres purified from an antenna-deficient strain of Rhodobacter sphaeroides. We find that mutation at the M210 position does not significantly perturb the distribution of the unpaired electron over the pair of bacteriochlorophyll molecules which constitute the primary donor radical cation. We conclude, therefore, that the effects of mutation of tyrosine M210 on the rate and asymmetry of primary electron transfer in reaction centres cannot be ascribed to a change in the electronic structure of the primary donor.
Jones
M R
MR
Robert Hill Institute for Photosynthesis, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, UK.
Heer-Dawson
M
M
Mattioli
T A
TA
Hunter
C N
CN
Robert
B
B
D001429:Bacteriochlorophylls / Q000737:chemistry; D003080:Cold Temperature; D004563:Electrochemistry; D004579:Electron Transport; D005583:Fourier Analysis; D045342:Light-Harvesting Protein Complexes; D015394:Molecular Structure; D016297:Mutagenesis, Site-Directed; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000235:genetics; D012242:Rhodobacter sphaeroides / Q000737:chemistry*; D013053:Spectrophotometry; D013059:Spectrum Analysis, Raman; D014443:Tyrosine / Q000235:genetics*
D001429:Bacteriochlorophylls; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D014443:Tyrosine