Environmental Effects on the Femtosecond−Picosecond Fluorescence Dynamics of Photoactive Yellow Protein: Chromophores in Aqueous Solutions and in Protein Nanospaces Modified by Site-Directed Mutagenesis

• DOI: 10.1021/jp982905t
• Publication Date: 2002-07-26T05:28:13Z
• Authors: Haik Chosrowjan; Noboru Mataga; Yutaka Shibata; Yasushi Imamoto; Fumio Tokunaga
• Keywords: Chromophore

The effect of the protein environment surrounding chromophores (protein nanospaces) on photoinduced ultrafast twisting in photoactive yellow (PYP) was investigated by comparing femtosecond−picosecond fluorescence dynamics wild type PYP with those chromophore aqueous solution as well nanospace modified site-directed mutagenesis. rate twisted state formation (the primary step trans → cis photoisomerization) demonstrated to be considerably enhanced compared solution. Moreover, results measurements mutagenesis implied that flipping thioester linkage slowed modifying structure a slightly looser one. Namely, more restricted wild-type seems best engineered for mechanism.