Preparation and spectral properties of the phycobilisomes from the red macroalga <i>Polysiphonia urceolata</i>.

<p>The phycobilisomes were prepared by sucrose step-gradient ultracentrifugation (a): a large fraction of phycobilisomes was situated within the boundary between 1.0 M and 1.5 M sucrose layers, and a small one was situated in the boundary between 1.5 M and 2.0 M sucrose layers; the former was used as samples for phycobiliprotein isolation and purification. Absorption (b solid line) and fluorescence emission (b dash dot line) spectra of the prepared intact phycobilisomes were recoded in pH 7.0 phosphate buffer at room temperature in which the phycobilisomes were excited at 498 nm.