The overarching goal of this work is to determine the molecular mechanisms that couple light absorption to the activation of downstream biological processes in flavoprotein photoreceptors. In collaboration with the laboratory of Pete Tonge at Stony Brook University, we complement static and dynamic X-ray crystallographic experiments with time-resolved spectroscopy to elucidate molecular details with a high level of spatial and temporal resolution. This work will significantly advance our understanding of fundamental signaling events and provide a foundation for optogenetic tools. We are also using our novel approach for time-resolved serial crystallography (CSAW), to obtain molecular movies of the dynamic structural features of the photoactive proteins under study. Our current work is focused on the blue light using FAD (BLUF) proteins and the Light Oxygen Voltage (LOV) class of photoreceptors.
Some of our recent publications in this area:
James N. Iuliano, Agnieszka A. Gil, Sergey P. Laptenok, Christopher R. Hall, Jinnette Tolentino Collado, Adras Lukacs, Safaa A Hag Ahmed, Taraneh Daryaee, Gregory M. Greetham, Igor V. Sazanovich, Boris Illarionov, Adelbert Bacher, Markus Fischer, Michael Towrie, Jarrod B. French, Stephen R. Meech, and Peter J. Tonge (2018) Variation in LOV photoreceptor activation dynamics probed by time resolved infrared spectroscopy. Biochemistry. 57(5): 620-630.
Agnieszka A. Gil, Sergey P. Laptenok, James N. Iuliano, Andras Kukacs, Anil Verma, Christopher R. Hall, EunBin Yoon, Richard Brust, Gregory M. Greetham, Michael Towrie, Jarrod B. French, Stephen R. Meech, and Peter J. Tonge (2017) Photoactivation of the BLUF protein PixD Probed by the Site-Specific Incorporation of Fluorotyrosine Residues. J. Am. Chem. Soc. 139(41): 14638-14648
Agnieszka A. Gil, Sergey P. Laptenok, Jarrod B. French, James N. Iuliano, Andras Lukacs, Christopher R. Hall, Igor V. Sazanovich, Gregory M. Greetham, Adelbert Bacher, Boris Illarionov, Markus Fischer, Peter J. Tonge and Stephen R. Meech (2017) Femtosecond to Millisecond Dynamics of Light Induced Allostery in the Avena sativa Lov Domain. J. Phys. Chem. B, 121(5): 1010-1019.
Agnieszka Gil, Allison Haigney, Sergey Laptenok, Richard Brust, Andras Lukacs, James Iuliano, Jessica Meng, Eduard Melief, Rui-Kun Zhao, EunBin Yoon, Ian Clark, Gregory Greetham, Annabelle Ng, James Truglio, Jarrod B. French, Stephen R. Meech, and Peter J. Tonge. (2015) The Mechanism of the AppaBLUF Photocycle Probed by Site-Specific Incorporation of Fluorotyrosine Residues: The Effect of the Y21 pKa on the Forward and Reverse Ground State Reactions. J. Am. Chem. Soc., 138: 926-935