The dynamics of structural deformations of immobilized single light-harvesting complexes.
نویسندگان
چکیده
Single assemblies of the intact light-harvesting complex LH2 from Rhodopseudomonas acidophila were bound to mica surfaces at 300 K and examined by observing their fluorescence after polarized light excitation. The complexes are generally not cylindrically symmetric. They act like elliptic absorbers, indicating that the high symmetry found in crystals of LH2 is not present when the molecules are immobilized on mica. The ellipticity and the principal axes of the ellipses fluctuate on the time scale of seconds, indicating that there is a mobile structural deformation. The B850 ring of cofactors shows significantly less asymmetry than B800. The photobleaching strongly depends on the presence of oxygen.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 96 20 شماره
صفحات -
تاریخ انتشار 1999