Biochemistry 1994, 33, 708-712
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A Conformational Change Associated with the Phototransformation of Pisum Phytochrome A As Probed by Fluorescence Quenching7 Todd A. Wells,$ Miki Nakazawa,s Katsushi Manabe,'*g and Pill-Soon Song'*$ Department of Chemistry and Institute for Cellular and Molecular Photobiology, University of Nebraska, Lincoln, Nebraska 68588-0304, and Department of Biology, Yokohama City University, Set0 22-2, Kanazawa-ku, Yokohama 236, Japan Received August 16, 1993; Revised Manuscript Received November I O , 1993'
ABSTRACT: Dynamic quenching of the two lifetime component tryptophan fluorescenceof Pisum phytochrome has revealed differential accessibility of certain residues. Both acrylamide and T1+ions showed preferential exposure of some tryptophans in Pfr-phytochrome. Greater k
