Multi-level, multi time-scale fluorescence intermittency of photosynthetic LH2 complexes: a precursor of non-photochemical quenching?

Schörner, M., Beyer, S. R., Southall, J., Cogdell, R. and Köhler, J. (2015) Multi-level, multi time-scale fluorescence intermittency of photosynthetic LH2 complexes: a precursor of non-photochemical quenching? Journal of Physical Chemistry B, 119(44), pp. 13958-13963. (doi: 10.1021/acs.jpcb.5b06979) (PMID:26419118)

Abstract

The light harvesting complex LH2 is a chromoprotein that is an ideal system for studying protein dynamics via the spectral fluctuations of the emission of its intrinsic chromophores. We have immobilized these complexes in a polymer film and studied the fluctuations of the fluorescence intensity from individual complexes over 9 orders of magnitude in time. Combining time-tagged detection of single photons with a change-point analysis has allowed the unambigeous identification of the various intensity levels due to the huge statistical basis of the data set. We propose that the observed intensity level fluctuations reflect conformational changes of the protein backbone that might be a precursor of the mechanism from which nonphotochemical quenching of higher plants has evolved.

• Item Type: Articles
• Additional Information: M.S., S.R.B., and J.K. thankfully acknowledge financial support by the Deutsche Forschungsgemeinschaft (DFG) within the project GRK1640 and the State of Bavaria within the initiative “Solar Technologies go Hybrid”. J.S. and R.J.C. thank the BBSRC for support.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cogdell, Professor Richard
• Authors: Schörner, M., Beyer, S. R., Southall, J., Cogdell, R., and Köhler, J.
• College/School: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Journal of Physical Chemistry B
• Publisher: American Chemical Society
• ISSN: 1520-6106
• ISSN (Online): 1990-7923