Project C3

Theoretical studies on the proton transfer process at the active site in phytochromes

Principal Investigator: Prof. Dr. Maria Andrea Mroginski (TU)

Structure and dynamics of the phytochrome photo­receptor will be investigated by combining molecular dynamics simulations, electrostatic Poisson-Boltzmann calculations and quantum chemistry. Calculation of vibrational spectra and comparison to experimental results is approached. One of the central goals is to understand the molecular mechanism leading to the release of a  proton in the so-called Meta R state, which likely is pivotal for the photoconversion of the bi-stable photoreceptor and consequently for phytochrome function.

Publications 2013 - 2017

Buhrke, D., Velazquez Escobar, F., Sauthof, L., Wilkening, S., Herder, N., Tavraz, N.N., Willoweit, M., Keidel, A., Utesch, T., Mroginski, M.A., Schmitt, F.J., Hildebrandt, P., and Friedrich, T. (2016). The role of local and remote amino acid substitutions for optimizing fluorescence in bacteriophytochromes: A case study on iRFP. Scientific Reports 6, 28444.

Otero, L.O., Klinke, S., Rinaldi, J., Velazquez Escobar, F., Mroginski, M.A., Fernandez Lopez, M., Malamud, F., Vojnov, A., Hildebrandt, P., Goldbaum, F.A., and Bonomi, H.R. (2016). Structure of the full-length bacteriophytochrome from the plant pathogen Xanthomonas campestris provides clues to its long-range signaling mechanism. Journal of Molecular Biology 428, 3702-3720.

Salewski, J., Escobar, F.V., Kaminski, S., von Stetten, D., Keidel, A., Rippers, Y., Michael, N., Scheerer, P., Piwowarski, P., Bartl, F., Frankenberg-Dinkel, N., Ringsdorf, S., Gaertner, W., Lamparter, T., Mroginski, M.A., and Hildebrandt, P. (2013). Structure of the Biliverdin Cofactor in the Pfr State of Bathy and Prototypical Phytochromes. Journal of Biological Chemistry 288, 16800-16814.

Sezer, M., Woelke, A.-L., Knapp, E.W., Schlesinger, R., Mroginski, M.A., Weidinger, I.M. (2017). Redox induced protonation of heme propionates in cytochrome c oxidase: Insights from surface enhanced resonance Raman spectroscopy and QM/MM calculations. Biochimica et Biophysica Acta (BBA) - Bioenergetics 1858, 103-108.

Stöppler, D., Song, C., van Rossum, B.-J., Geiger, M.-A., Lang, C., Mroginski, M.-A., Jagtap, A.P., Sigurdsson, S.T., Matysik, J., Hughes, J., and Oschkinat, H. (2016). Dynamic nuclear polarization provides new insights into chromophore structure in phytochrome photoreceptors. Angewandte Chemie International Edition 55, 16017-16020.

Takiden, A., Velazquez-Escobar, F., Dragelj, J., Woelke, A.L., Knapp E.-W., Piwowarski, P., Bartl, F., Hildebrandt, P., and Mroginski, M.A. (2017). Structural and Vibrational Characterization of the Chromophore Binding Site of Bacterial Phytochrome Agp1. Photochemistry and Photobiology 93, 713-723.

Velázquez Escobar, F., Buhrke, D., Michael, N., Sauthof, L., Wilkening, S., Tavraz, N.N., Salewski, J., Frankenberg-Dinkel, N., Mroginski, M.A., Scheerer, P., Friedrich, T., Siebert, F., and Hildebrandt, P. (2017). Common Structural Elements in the Chromophore Binding Pocket of the Pfr State of Bathy Phytochromes. Photochemistry and Photobiology 93, 724-732.

Velazquez Escobar, F., Hildebrandt, T., Utesch, T., Schmitt, F.J., Seuffert, I., Michael, N., Schulz, C., Mroginski, M.A., Friedrich, T., and Hildebrandt, P. (2014). Structural Parameters Controlling the Fluorescence Properties of Phytochromes. Biochemistry 53, 20-29.

Velazquez Escobar, F., Lang, C., Takiden, A., Schneider, C., Balke, J., Hughes, J., Alexiev, U., Hildebrandt, P., and Mroginski, M.A. (2017). Protonation-Dependent Structural Heterogeneity in the Chromophore Binding Site of Cyanobacterial Phytochrome Cph1. Journal of Physical Chemistry B 121, 47-57.

Velazquez Escobar, F., Piwowarski, P., Salewski, J., Michael, N., Fernandez Lopez, M., Rupp, A., Muhammad Qureshi, B., Scheerer, P., Bartl, F., Frankenberg-Dinkel, N., Siebert, F., Mroginski, M.A., and Hildebrandt, P. (2015). A protonation-coupled feedback mechanism controls the signalling process in bathy phytochromes. Nature Chemistry 7, 423-430. [Link to news section.]

Velazquez Escobar, F., Utesch, T., Narikawa, R., Ikeuchi, M., Mroginski, M.A., Gaertner, W., and Hildebrandt, P. (2013). Photoconversion Mechanism of the Second GAF Domain of Cyanobacteriochrome AnPixJ and the Cofactor Structure of Its Green-Absorbing State. Biochemistry 52, 4871-4880.

Velazquez Escobar, F., von Stetten, D., Günther-Lütkens, M., Keidel, A., Michael, N., Lamparter, T., Essen, L.-O., Hughes, J., Gärtner, W., Yang, Y., Heyne, K., Mroginski, M.A., and Hildebrandt, P. (2015). Conformational heterogeneity of the Pfr chromophore in plant and cyanobacterial phytochromes. Frontiers in Molecular Biosciences 2, 37.