Structural heterogeneity in a parent ground-state structure of AnPixJg2 revealed by theory and spectroscopy. Issue 21 (17th May 2017)

• Record Type: Journal Article
• Authors: Scarbath-Evers, Laura Katharina; Jähnigen, Sascha; Elgabarty, Hossam; Song, Chen; Narikawa, Rei; Matysik, Jörg; Sebastiani, Daniel
• Is Part Of: Physical chemistry chemical physics. Volume 19:Issue 21(2017)
• Page Start: 13882
• Page End: 13894
• Publication Date: 2017-05-17
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp01218g
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Extensive molecular dynamics simulations reveal two distinct isoforms of the cyanobacteriochrome AnPixJg2 (in its Pr state) with different chromophore conformations, yielding implications for spectroscopic properties. Abstract : We investigated the red absorbing, dark stable state (Pr state) of the second GAF domain of the cyanobacteriochrome AnPixJ (AnPixJg2) by a molecular dynamics simulation of 1 μs duration. Our results reveal two distinct conformational isoforms of the chromophore, from which only one was known from crystallographic experiments. The interconversion between both isoforms is accompanied by alterations in the hydrogen bond pattern between the chromophore and the protein and the solvation structure of the chromophore binding pocket. The existence of sub-states in the Pr form of AnPixJg2 is supported by the results from experimental 13 C MAS NMR spectroscopy. Our finding is consistent with the observation of structural heterogeneity in other cyanobacteriochromes and phytochromes.