Acknowledgelements

We thank James Duncan for helping with the Chl analyses. J.B. and A.W.D.L. acknowledge the Biotechnology and Biological Research Council and Australian Research Council, respectively, for financial support. J.N. holds a Royal Society University fellowship.

Abbreviations: PSI and PSII, photosystems I and II, respectively; Chl, chlorophyll; RT, room
temperature.
‡To whom correspondence should be addressed. E-mail: j.barber@imperial.ac.uk.
www.pnas.org/cgi/doi/10.1073/pnas.1532271100