TY - JOUR
T1 - Time-resolved crystallographic studies of light-induced structural changes in the photosynthetic reaction center
AU - Baxter, Richard H.G.
AU - Ponomarenko, Nina
AU - Šrajer, Vukica
AU - Pahl, Reinhard
AU - Moffatt, Keith
AU - Norris, James R.
PY - 2004/4/20
Y1 - 2004/4/20
N2 - Light-induced structural changes in the bacterial reaction center were studied by a time-resolved crystallographic experiment. Crystals of protein from Blastochloris viridis (formerly Rhodopseudomonas viridis) were reconstituted with ubiquinone and analyzed by monochromatic and Laue diffraction, in the dark and 3 ms after illuminating the crystal with a pulsed laser (630 nm, 3 mJ/pulse, 7 ns duration). Refinement of monochromatic data shows that ubiquinone binds only in the "proximal" QB binding site. No significant structural difference was observed between the light and dark datasets; in particular, no quinone motion was detected. This result may be reconciled with previous studies by postulating equilibration of the "distal" and "proximal" binding sites upon extended dark adaption, and in which movement of ubiquinone is not the conformational gate for the first electron transfer between QA and QB.
AB - Light-induced structural changes in the bacterial reaction center were studied by a time-resolved crystallographic experiment. Crystals of protein from Blastochloris viridis (formerly Rhodopseudomonas viridis) were reconstituted with ubiquinone and analyzed by monochromatic and Laue diffraction, in the dark and 3 ms after illuminating the crystal with a pulsed laser (630 nm, 3 mJ/pulse, 7 ns duration). Refinement of monochromatic data shows that ubiquinone binds only in the "proximal" QB binding site. No significant structural difference was observed between the light and dark datasets; in particular, no quinone motion was detected. This result may be reconciled with previous studies by postulating equilibration of the "distal" and "proximal" binding sites upon extended dark adaption, and in which movement of ubiquinone is not the conformational gate for the first electron transfer between QA and QB.
KW - Crystallography, X-Ray
KW - Fourier Analysis
KW - Light
KW - Models, Molecular
KW - Photosynthetic Reaction Center Complex Proteins/chemistry
KW - Protein Conformation
KW - Rhodopseudomonas/chemistry
UR - http://www.scopus.com/inward/record.url?scp=1942469425&partnerID=8YFLogxK
U2 - 10.1073/pnas.0306840101
DO - 10.1073/pnas.0306840101
M3 - Article
C2 - 15073325
AN - SCOPUS:1942469425
SN - 0027-8424
VL - 101
SP - 5982
EP - 5987
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 16
ER -