Spectral deconvolution analysis and calculation of energy transfer efficiency were as in Croce et al.,, 1999 . The data, normalized to the WT, are relative to a 100% Chl a-to-Chl a ET efficiency. The error in the ET efficiency was <4%, with the exception of Viola1 in WT (>10%). Xanthophyll absorption maxima in ethanol are 477.2, 472.8 and 468.4 nm, respectively, for violaxanthin, lutein and neoxanthin. Binding to sites L2 and L1 shifts violaxanthin absorption from 477.2 to 492 and 505 nm respectively; lutein is shifted from 472.8 to 489 and 495 nm, respectively. Binding to site N1 shifts neoxanthin from 468.4 to 486.5 nm.