Aggregation Of Chlorophyll a Probed By Resonance Light Scattering Spectroscopy

Authors

J. C. de PaulaFollow
J. H. Robblee
Robert F. Pasternack, Swarthmore CollegeFollow

Document Type

Article

Publication Date

1-1-1995

Published In

Biophysical Journal

Abstract

We report the resonance light scattering (RLS) spectra of chlorophyll a aggregated in a 9:1 solution of formamide and pH 6.8 phosphate buffer. The aggregate formed after 2 h of mixing, referred to as Chl(469), shows a strong scattering feature at 469 nm (Soret band) and a much weaker feature at 699 nm (Q(y) band). A kinetic investigation confirmed that the aggregation process is cooperative, and also detected one intermediate (Chl(458)) with a strong RLS spectrum but only a weak CD spectrum. We propose that aggregation proceeds via at least three steps: 1) formation of a nucleating species, probably a dimer of chlorophylls; 2) formation of large aggregates with little or no secondary structure (e.g., Chl(458)); and 3) conformational change to form helical aggregate (Chl(469)).

Comments

This work is freely available courtesy of the Biophysical Society and Elsevier.

Recommended Citation

J. C. de Paula, J. H. Robblee, and Robert F. Pasternack. (1995). "Aggregation Of Chlorophyll a Probed By Resonance Light Scattering Spectroscopy". Biophysical Journal. Volume 68, Issue 1. 335-341. DOI: 10.1016/s0006-3495(95)80192-x
https://works.swarthmore.edu/fac-chemistry/109