Reaction Centers of Photosynthetic Bacteria: Feldafing-II-Meeting

ISBN-13: 9783642647819 / Angielski / Miękka / 2011 / 469 str.

M. -E Michel-Beyerle

Opis

Reaction Centers of Photosynthetic Bacteria is an updated record on the most recent insight into the struc- ture/function relationship of reaction centers from photosynthetic bacteria. It addresses in particular, interactions and dynamics which determine the ultra-high quantum yield of photoinduced charge separation in these energy-transforming molecular machines. Of particular interest is the still controversial issue of the primary charge separation mechanism as well as the effects of well-defined modifications, introduced either by mutagenic replacements in the protein matrix or by chemical exchange of reaction center pigments. Also described are the methods used for the characterization of interactions and dynamics important for electron transfer processes in the reaction center.

Spis treści

I Native Reaction Centers: Structure and Spectroscopy.- Reaction Center from Wild Type Y Rhodobacter sphaeroides: Primary Structure of the L and M Subunits; Carotenoid and Detergent Structures in the Three-Dimensional Crystals.- Probing Reaction Center Asymmetry Using Low Temperature Absorption Spectroscopy of Rhodobacter sphaeroides Reaction Centers Containing Bacteriopheophytin Anions.- Cytochrome Arrangement in Reaction Centers of Different Species of Photosynthetic Bacteria.- Infrared Difference Spectroscopy of Electrochemically Generated Redox States in Bacterial Reaction Centers.- EPR and ENDOR Studies of the Oxidized Primary Donor in Single Crystals of Reaction Centers of Rhodobacter sphaeroides R-26.- ENDOR and TRIPLE Resonance Investigation of the Primary Donor Cation Radical P+865 in Single Crystals of Rhodobacter sphaeroides R-26 Reaction Centers.- Triplet State ADMR of Bacterial Reaction Centers at Low Transition Frequencies.- Investigation of Quinone Reduction in Rhodopseudomonas viridis by FTIR Difference Spectroscopy and X-Ray Diffraction Analysis.- Steady-State and Time-Resolved FTIR Spectroscopy of Quinones in Bacterial Reaction Centers.- II Native Reaction Centers: Electron Transfer Dynamics.- Spectral Hole Burning Studies of Photosystem II Reaction Centers: Excited State Structure, Charge Separation and Energy Transfer Dynamics.- Evidence for an Inhomogeneous Distribution of Reaction Centers on the Timescale of the Primary Electron Transfer Events.- Analysis of Transient Absorption Data from Reaction Centers of Purple Bacteria.- Similarities of the Primary Charge Separation Process in the Photosynthesis of Rhodobacter sphaeroides and Rhodopseudomonas viridis.- Picosecond Resonance Raman Spectroscopy of Rhodobacter sphaeroides Reaction Centers.- Electric Field Modulation of the Fluorescence Lineshape for Photosynthetic Reaction Centers: A New Probe of the Primary Electron Transfer Mechanism.- One Step Electron Transfer to P+H? in Reaction Centers of Rhodobacter sphaeroides Derived from Dichroic Excitation Spectra of Electric Field Modulated Fluorescence Yield.- Energy Transfer and Charge Separation Kinetics in the Reaction Center of Chloroflexus aurantiacus Studied by Picosecond Time-Resolved Fluorescence Spectroscopy.- Biexponential Charge Separation and Monoexponential Decay of P+H? in Reaction Centers of Chloroflexus aurantiacus.- Analog Effects of Low Temperature and Lipid Rigidity on the Distribution of Two Conformational States of the Reaction Centers.- III Modified Reaction Centers: Effects of Mutagenic and Chemical Modifications.- Recent Advances in the Structure Analysis of RhodoPseudomonas viridis Reaction Center Mutants.- Genetic Coding Algorithms for Engineering Membrane Proteins.- EPR and ENDOR Studies of the Oxidized Donor in Reaction Centers of Rhodobacter sphaeroides Strain R-26 and two Heterodimer Mutants in which Histidine M202 or LI73 was Replaced by Leucine.- Site-Directed Mutations Affecting Primary Photochemistry in Reaction Centers: Effects of Dissymmetry in the Special Pair.- Electrostatic Effects on the Speed and Directionality of Electron Transfer in Bacterial Reaction Centers: The Special Role of Tyrosine M-208.- The Role of Tyrosine M210 in the Initial Charge Separation in the Reaction Center of Rhodobacter sphaeroides.- Site-Directed Mutagenesis of Threonine M222 and Tryptophan M252 in the Photosynthetic Reaction Center of Rhodobacter sphaeroides.- Influence of Mutagenic Replacement of Tryptophan M250 on Electron Transfer Rates Involving Primary Quinone in Reaction Centers of Rhodobacter capsulatus.- Transmembrane Helix Exchanges Between Quasi-Symmetric Subunits of the Photosynthetic Reaction Center.- Ground State and Femtosecond Transient Absorption Spectroscopy of a Mutant of Rhodobacter capsulatus which Lacks the Initial Electron Acceptor Bacteriopheophytin.- Preliminary Characterization of pAT-3, a Symmetry Enhanced Reaction Center Mutant of Rhodobacter capsulatus.- Modified Bacterial Reaction Centers: 3. Chemically Modified Chromophores at Sites BA, BB and HA, HB.- Effect of Cofactor Structure on Control of Electron Transfer Rates at the QA Site of the Reaction Center Protein.- IV Reaction Centers: Modelling of Structure/Function-Relationship.- Energy Transfer and Trapping in Spectrally Disordered Photosynthetic Membranes.- Multi-Step Electron Transfer in Rigid Photosynthetic Models at Low Temperature: Requirements for Charge Separation and Spin-Polarized Radical Ion Pair Formation.- Electronic Couplings for Light Induced Charge Transfer in Covalently Bonded Donor-Acceptor Systems.- Micro-Environmental Effects on Photosynthetic Chromophores.- Simulation of the Absorption and Circular Dichroism Spectra for the Primary Electron Donor in Reaction Centers of Purple Bacteria and Photosystem II.- On the Primary Charge Separation in Bacterial Photosynthesis.- Multiple Excited States of Photosynthetic Reaction Centers.- Exciton Band Mixing in Rhodopseudomonas viridis.- An Extended Model for Electron Spin Polarization in Photosynthetic Bacteria.- Can Electron Transfer be Influenced by Protein Dynamics: The Transfer from Cytochrome C to the Special Pair in Photosynthetic Reaction Centers.- Concluding Remarks.- Beyond Native Reaction Centers.

O autorze

Rooted in the crystal structure of the reaction center of meanwhile two bacterial organisms, the present compilation of invited papers points in a self-evident way to the different lines of developments in a still vividly expanding field. The abundance of open questions initiated also novel methodological approaches spanning a wide bow from biochemistry and genetic engineering over complex spectroscopies to chemical modelling, molecular dynamics calculations and electron transfer theory.