title: Changes in the hydrogen-bond network around the chromophore of photoactive yellow protein in the ground and excited states.
abstract: Changes in the hydrogen-bond (HB) network around the chromophore, p-coumaric acid (pCA), in the ground pG and excited pG* states were investigated for wild type (WT) photoactive yellow protein (PYP) and its mutants using ultraviolet resonance Raman (UVRR) spectroscopy. The intensity depletion of Tyr UVRR bands was observed upon photoexcitation of pCA to the pG* state. The spectral change was ascribed to strengthening of HB between pCA and Tyr42. Comparison of Raman intensities indicated that, in the pG state, the HB between pCA and Tyr42 in WT is a short HB, which is weaker than that in E46Q mutant. In the pG* state, the HB network around pCA of WT is similar to that of E46Q mutant. The present results demonstrate that the HB between pCA and Tyr42 and that between pCA and Glu46 are correlated with each other in the HB network.
authors.affiliation: Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
authors.forename: Misao
authors.initials: M
authors.lastname: Mizuno
authors.forename: Hironari
authors.initials: H
authors.lastname: Kamikubo
authors.forename: Mikio
authors.initials: M
authors.lastname: Kataoka
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Mizutani
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003373:Coumaric Acids / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009154:Mutation; D020283:Photoreceptors, Microbial / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011422:Propionates; D011487:Protein Conformation; D013059:Spectrum Analysis, Raman; D013997:Time Factors; D014443:Tyrosine; D014466:Ultraviolet Rays
chemical_list: D001426:Bacterial Proteins; D003373:Coumaric Acids; D020283:Photoreceptors, Microbial; D011422:Propionates; C050162:photoactive yellow protein, Bacteria; D014443:Tyrosine; C495469:p-coumaric acid