TU Berlin

Physikalische Chemie / Biophysikalische ChemieArticles

Inhalt des Dokuments

zur Navigation


Structure of the Full-Length Bacteriophytochrome from the Plant Pathogen Xanthomonas campestris Provides Clues to its Long-Range Signaling Mechanism
Zitatschlüssel Otero20163702
Autor Lisandro Horacio Otero and Sebastián Klinke and Jimena Rinaldi and Francisco Velázquez-Escobar and María Andrea Mroginski and María Fernández López and Florencia Malamud and Adrián Alberto Vojnov and Peter Hildebrandt and Fernando Alberto Goldbaum and Hernán Ruy Bonomi
Seiten 3702 - 3720
Jahr 2016
ISSN 0022-2836
DOI http://dx.doi.org/10.1016/j.jmb.2016.04.012
Journal Journal of Molecular Biology
Jahrgang 428
Nummer 19
Notiz Molecular Basis of Signal Transduction
Zusammenfassung Abstract Phytochromes constitute a major superfamily of light-sensing proteins that are reversibly photoconverted between a red-absorbing (Pr) and a far-red-absorbing (Pfr) state. Bacteriophytochromes (BphPs) are found among photosynthetic and non-photosynthetic bacteria, including pathogens. To date, several BphPs have been biophysically characterized. However, it is still not fully understood how structural changes are propagated from the photosensory module to the output module during the signal transduction event. Most phytochromes share a common architecture consisting of an N-terminal photosensor that includes the PAS2–GAF–PHY domain triad and a C-terminal variable output module. Here we present the crystal structure of the full-length BphP from the plant pathogen Xanthomonas campestris pv. campestris (XccBphP) bearing its photosensor and its complete output module, a \PAS9\ domain. In the crystals, the protein was found to be in the Pr state, whereas diffraction data together with resonance Raman spectroscopic and theoretical results indicate a \ZZZssa\ and a \ZZEssa\ chromophore configuration corresponding to a mixture of Pr and Meta-R state, the precursor of Pfr. The XccBphP quaternary assembly reveals a head-to-head dimer in which the output module contributes to the helical dimer interface. The photosensor, which is shown to be a bathy-like BphP, is influenced in its dark reactions by the output module. Our structural analyses suggest that the photoconversion between the Pr and Pfr states in the full-length XccBphP may involve changes in the relative positioning of the output module. This work contributes to understand the light-induced structural changes propagated from the photosensor to the output modules in phytochrome signaling.
Link zur Publikation Download Bibtex Eintrag



Schnellnavigation zur Seite über Nummerneingabe