J.A. Kyndt,, J.C. Fitch, S. Seibeck, B. Borucki, M.P. Heyn, T.E. Meyer, and M.A. Cusanovich Regulation of the Ppr histidine kinase by light-induced interaction between its photoactive yellow protein and bacteriophytochrome domains. Biochemistry 49, 1744-1754 (2010).
C.P. Joshi, H. Otto, D. Hoersch, T. E. Meyer, M.A. Cusanovich, and M.P. Heyn Strong Hydrogen Bond between Glutamic Acid 46 and Chromophore Leads to the Intermediate Spectral Form and Excited State Proton Transfer in the Y42F Mutant of the Photoreceptor Photoactive Yellow Protein. Biochemistry 48, 9980-9993 (2009).
D. Hoersch, H. Otto, M.A. Cusanovich, and M.P. Heyn Time-resolved spectroscopy of dye-labeled photoactive yellow protein suggests a pathway of light-induced structural changes in the N-terminal cap. Phys.Chem.Chem.Phys.11, 5437-5444 (2009).
B. Borucki, S. Seibeck, M.P. Heyn, and T. Lamparter Characterization of the covalent and noncovalent adducts of Agp1 phytochrome assembled with biliverdin and phycocyanobilin by circular dichroism and flash photolysis . Biochemistry 48, 6305-6317 (2009).
D. Hoersch, H. Otto, M.A.Cusanovich, and M.P. Heyn Distinguishing chromophore structures of photocycle intermediates of the photoreceptor PYP by transient fluorescence and energy transfer. J.Phys.Chem. B112, 9118-9125 (2008).
D. Hoersch, H. Otto, I. Wallat and M.P. Heyn Monitoring the conformational changes of photoactivated rhodopsin from microseconds to seconds by transient fluorescence spectroscopy. Biochemistry47, 11518-11527 (2008).
D. von Stetten, S. Seibeck, N. Michael, P. Scheerer, M.A. Mroginski, D.H. Murgida, N. Krauß, M.P. Heyn, P. Hildebrandt, B. Borucki, T. Lamparter Highly conserved residues D197 and H250 in Agp1 phytochrome control the proton affinity of the chromophore and Pfr formation. J. Biol. Chem.282, 2116-2123 (2007).
J.A. Kyndt, S.N. Savvides, S. Memmi, M. Koch, J.C. Fitch, T.E. Meyer, M.P. Heyn, J.J. van Beeumen, and M.A. Cusanovich Structural role of tyrosine 98 in the photoactive yellow protein: effects on fluorescence, gateway and photocycle recovery. Biochemistry46, 95-105 (2007).
D. Hoersch, H. Otto, C. P. Joshi, B. Borucki, M. A. Cusanovich, M. P. Heyn Role of a conserved salt bridge between the PAS core and the N-terminal domain in the activation of the photoreceptor Photoactive Yellow Protein Biophys.J.93, 1687-1699 (2007).
S. Seibeck, B. Borucki, H. Otto, K. Inomata, H. Khawn, H. Kinoshita, N. Micheal, T. Lamparter, M. P. Heyn Locked 5Zs-biliverdin blocks the Meta-RA to Meta-RC transition in the functional cycle of bacteriophytochrome Agp1. FEBS Letters581, 5425-5429 (2007).
M.F. Brown, M.P. Heyn, C. Job, S. Kim, S. Moltke, K. Nakanishi, A.A. Nevzorov, A.V. Struts, G.F.J. Salgado, I. Wallat Solid-State 2H NMR Spectroscopy of Retinal Proteins in Aligned Membranes Biophys.Biochem. Acta1768, 2979-3000 (2007).
C.P. Joshi, B. Borucki, H. Otto, T.E. Meyer, M.A. Cusanovich and M.P. Heyn Photocycle and photoreversal of photoactive yellow protein at alkaline pH: kinetics, intermediates and equilibria. Biochemistry45, 7057 - 7068 (2006).
B. Borucki, C.P. Joshi, H. Otto, M.A. Cusanovich, and M.P. Heyn The transient accumulation of the signaling state of photoactive yellow protein is controlled by the external pH. Biophys. J.91, 2991 - 3001 (2006).
M. Birkholz, P. Zaumseil, M. Kittler, I. Wallat, and M.P. Heyn Structure of biomembrane - on - silicon derived from X-ray reflectometry. Materials Science and EngineeringB 134, 125-129 (2006).
B. Borucki, H. Otto, S. Seibeck and M.P. Heyn Synchrotron radiation circular dichroism (SRCD) reveals structural changes in the photoreceptors phytochrome and photoactive yellow protein (PYP). In:"Research with synchrotron radiation", H.Dau, W.Kuch and R Puettner , eds, Shaker Verlag, 85-87 (2006).
C.P.Joshi, B. Borucki, H. Otto, T.E. Meyer, M.A. Cusanovich and M.P. Heyn Photoreversal kinetics of the I1 and I2 intermediates in the photocycle of photoactive yellow protein by double flash experiments with variable time delay. Biochemistry44, 656-665 (2005).
B. Borucki, D. von Stetten, S. Seibeck, T. Lamparter, N. Michael, M.A. Mroginski, H. Otto, D. H. Murgida, M.P. Heyn and P. Hildebrandt. Light-induced proton release of phytochrome is coupled to the transient deprotonation of the tetrapyrrole chromophore. J. Biol. Chem. 280, 34358-34364 (2005).
B. Borucki, J.A. Kyndt, C.P. Joshi, H. Otto, T.E. Meyer, M.A. Cusanovich and M.P. Heyn Effect of salt and pH on the activation of photoactive yellow protein and gateway mutants Y98Q and Y98F. Biochemistry44, 13650-13663 (2005).
H. Otto, D. Hoersch, T.E. Meyer, M.A. Cusanovich and M.P. Heyn Time-Resolved Single Tryptophan Fluorescence in Photoactive Yellow Protein Monitors Changes in the Chromophore Structure during the Photocycle via Energy Transfer. Biochemistry44, 16804-16816 (2005).
H.Otto, T. Lamparter, B. Borucki, J. Hughes and M.P. Heyn. Dimerization and Inter-Chromophore Distance of Cph1 Phytochrome from Synechocystis, as Monitored by Fluorescence Homo and Hetero Energy Transfer. Biochemistry42, 5885-5895 (2003).
B. Borucki, H. Otto, C.P. Joshi, C. Gasperi, M.A. Cusanovich, S. Devanathan, G. Tollin and M.P. Heyn. pH Dependence of the Photocycle Kinetics of the E46Q Mutant of Photoactive Yellow Protein: Protonation Equilibrium between I1 and I2 Intermediates, Chromophore Deprotonation by Hydroxyl Uptake, and Protonation Relaxation of the Dark State. Biochemistry42, 8780-8790 (2003).
B. Borucki, H. Otto, G. Rottwinkel, J. Hughes, M.P. Heyn and T. Lamparter. Mechanism of Cph1 Phytochrome Assembly from Stopped-Flow Kinetics and Circular Dichroism. Biochemistry42, 13684-13697 (2003).
T. Mielke, C. Villa, P.C. Edwards, G.F.X. Schertler and M.P. Heyn. X-ray diffraction of heavy-atom labelled two-dimensional crystals of rhodopsin identifies the position of cysteine 140 in helix 3 and cysteine 316 in helix 8. Journal Mol. Biol.316, 693-709 (2002).
T. Mielke, U. Alexiev, M. Gläsel, H. Otto, and M.P. Heyn. Light-induced changes in the structure and accessibility of the cytoplasmic loops of rhodopsin in the activated MII-state. Biochemistry41, 7875-7884 (2002).
B. Borucki, S. Devanathan, H. Otto, M.A. Cusanovich, G. Tollin and M.P. Heyn. Kinetics of proton uptake and dye binding by Photoactive Yellow Protein in wild-type, and in the E46Q and E46A mutants. Biochemistry,41, 10026-10037(2002).
R. A. Krebs, U. Alexiev, R. Parthasarathy, A.M. DeVita and M.S. Braiman Detection of fast light-activated H+ release and M intermediate formation from proteorhodopsin BioMed Central Physiology2:5(2002).
M.P. Heyn, B. Borucki and H. Otto. Chromophore reorientation during the photocycle of bacteriorhodopsin: experimental methods and functional significance. Biochim. Biophys. Acta1460, 60-74 (2000).
K. Heyne, J. Herbst, B. Dominguez-Herradon, U. Alexiev and R. Diller. Reaction Control in Bacteriorhodopsin: Impact of Arg82 and Asp85 on the fast Retinal Isomerization, Studied in the Second Site Revertant Arg82Ala/Gly231Cys and Various Purple and Blue Forms of Bacteriorhodopsin. J. Phys. Chem.B 104, 6053-6058 (2000).
M.S. Hutson, U. Alexiev, S.V. Shilov, K.J. Wise, and M.S. Braiman. Evidence for a Perturbation of Arginine-82 in the Bacteriorhodopsin Photocycle from Time-Resolved Infrared Spectra. Biochemistry39, 13189-13200 (2000).
A. Nevzorov, S. Moltke, M.P. Heyn and M.F. Brown. Solid-State NMR line shapes of uniaxiallly oriented immobile systems. J. Am. Chem. Soc.121, 7636-7643 (1999).
B. Borucki, H. Otto, and M.P. Heyn. Reorientation of the retinylidene chromophore in the K, L and M intermediates of bacteriorhodopsin from time-resolved linear dichroism: Resolving kinetically and spectrally overlapping intermediates of chromoproteins. J. Phys. Chem.B 103, 6371-6383 (1999).
W. Behrens, H. Otto, H.B. Stuhrmann and M.P. Heyn. Sulfur distribution in bacteriorhodopsin from multiple wavelength anomalous diffraction near the sulfur K-edge with synchrotron X-ray radiation. Biophys. J.75, 255-263 (1998).
B. Borucki, H. Otto and M.P. Heyn. Linear dichroism measurements on oriented purple membranes between parallel polarizers: contribution of linear birefringence and applications to chromophore isomerization. J. Phys. Chem.102, 3821-3829 (1998).
S. Moltke, A.A. Nevzorov, N. Sakai, I. Wallat, C. Job, K. Nakanishi, M.F. Brown and M.P. Heyn. Chromophore Orientation in Bacteriorhodopsin Determined from the Angular Dependence of Deuterium Nuclear Magnetic Resonance Spectra of Oriented Purple Membranes. Biochemistry37,11821-11835 (1998).
S. Dickopf, T. Mielke and M.P. Heyn. Kinetics of the Light-Induced Proton Translocation Associated with the pH-Dependent Formation of the Metarhodopsin I/II Equilibrium of Bovine Rhodopsin. Biochemistry37,16888-16897 (1998).
U. Alexiev, R. Mollaaghababa, P. Scherrer, H.G. Khorana and M.P. Heyn. Rapid long-range proton diffusion along the surface of the purple membrane and delayed proton transfer into the bulk. Proc. Natl. Acad. Sci. USA92, 372-376 (1995).
H. Otto, C. Zscherp, B. Borucki and M.P. Heyn. Time-resolved polarized absorption spectroscopy with isotropically excited oriented purple membranes: The orientation of the electronic transition dipole moment of the chromophore in the O-intermediate of bacteriorhodopsin. J. Phys. Chem.99, 3847-3853 (1995).
B. Watts, A.S. Sternberg, C.A. Ulrich, G. Whiteway, M. Seifert, P. Sami, P. Fisher, M.P. Heyn and I. Wallat. Bacteriorhodopsin: the effect of bilayer thickness on 2D-array formation and the structural re-alignment of retinal through the photocycle. Biophysical Chemistry56, 41-46 (1995).
U. Alexiev, P. Scherrer, T. Marti, H.G. Khorana and M.P. Heyn. Time-resolved surface charge change on the cytoplasmic side of bacteriorhodopsin during the decay of the M-intermediate. FEBS Letters373, 81-84 (1995).
S. Moltke and M.P. Heyn. Photovoltage kinetics of the acid-blue and acid-purple forms of bacteriorhodopsin: evidence for no net charge transfer. Biophys. J.69, 2066-2073 (1995).
S. Moltke, M.P. Krebs, R. Mollaaghababa, H.G. Khorana and M.P. Heyn. Intramolecular charge transfer in the bacteriorhodopsin mutants Asp85 -> Asn and Asp212 -> Asn: effects of pH and anions. Biophys. J.69, 2074-2083 (1995).
S. Moltke, U. Alexiev and M.P. Heyn. Kinetics of light-induced intramolecular charge transfer and proton release in bacteriorhodopsin. Israel J.Chem.35, 401-414 (1995).
S. Dickopf, U. Alexiev, M.P. Krebs, H. Otto, R. Mollaaghababa, H.G. Khorana and M.P. Heyn. Proton transport by a bacteriorhodopsin mutant, aspartic acid 85-> asparagine, initiated in the unprotonated Schiff base state. Proc. Natl. Acad. Sci. USA92, 11519-11523 (1995).
T. Hauß, G. Büldt, M.P. Heyn and N.A. Dencher. Light-induced isomerisation causes an increase in the chromophore tilt in the M-intermediate of bacteriorhodopsin: A neutron diffraction study. Proc. Natl. Acad. Sci. USA91, 11854-11858 (1994).
A.S. Ulrich, I. Wallat, A. Watts and M.P. Heyn. Distorted structure of the retinal chromophore in bacteriorhodopsin resolved by 2H-NMR. Biochemistry33, 5370-5375 (1994).
P. Scherrer, U. Alexiev, T. Marti, H.G. Khorana and M.P. Heyn. Covalently bound pH-indicator dyes at selected extracellular or cytoplasmic sites in bacteriorhodopsin. 1. Proton migration along the surface of bacteriorhodopsin micelles and its delayed transfer from surface to bulk. Biochemistry33, 13684-13692 (1994).
U. Alexiev, T. Marti, M.P. Heyn, H.G. Khorana and P. Scherrer. Covalently bound pH-indicator dyes at selected extracellular or cytoplasmic sites in bacteriorhodopsin. 2. Rotational orientation of helices D and E and kinetic correlation between M formation and proton release in bacteriorhodopsin micelles. Biochemistry33, 13693-13699 (1994).