title: Mechanistic pathways for the photoisomerization reaction of the anchored, tethered chromophore of the photoactive yellow protein and its mutants.
abstract: We show by way of physical organic reasoning that the currently known photochemical results of the chromophore of photoactive yellow protein (PYP) are consistent with that expected of a least volume-demanding process for an anchored, tethered chromophore. The primary photoreaction, interestingly, does not appear to involve a hula-twist process. However, the latter might be involved during subsequent transition of dark intermediates. Absorption data of intermediates obtained from a microsecond time-resolved spectroscopic study of three PYP mutants (E46Q, T50V and R52Q) are consistent with the above analyses.
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Imamoto
authors.forename: Mikio
authors.initials: M
authors.lastname: Kataoka
authors.forename: Robert S H
authors.initials: RS
authors.lastname: Liu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D007536:Isomerism; D009154:Mutation / Q000235:genetics*; D010777:Photochemistry; D020283:Photoreceptors, Microbial / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011487:Protein Conformation / Q000528:radiation effects; D013057:Spectrum Analysis; D013997:Time Factors
chemical_list: D001426:Bacterial Proteins; D020283:Photoreceptors, Microbial; C050162:photoactive yellow protein, Bacteria