Bacteriopheophytin triplet state in Rhodobacter sphaeroides reaction centers

Early bacteriopheophytin reduction in charge separation in reaction centers of Rhodobacter sphaeroides.

A question at the forefront of biophysical sciences is, to what extent do quantum effects and protein conformational changes play a role in processes such as biological sensing and energy conversion? At the heart of photosynthetic energy transduction lie processes involving ultrafast energy and electron transfers among a small number of tetrapyrrole pigments embedded in the interior of a protei...

Supporting Information Early bacteriopheophytin reduction in charge separation in reaction centers of Rhodobacter sphaeroides

Temperature dependence of electron transfer to the M-side bacteriopheophytin in rhodobacter capsulatus reaction centers.

Subpicosecond time-resolved absorption measurements at 77 K on two reaction center (RC) mutants of Rhodobacter capsulatus are reported. In the D(LL) mutant the D helix of the M subunit has been substituted with the D helix from the L subunit, and in the D(LL)-FY(L)F(M) mutant, three additional mutations are incorporated that facilitate electron transfer to the M side of the RC. In both cases th...

Specific alteration of the oxidation potential of the electron donor in reaction centers from Rhodobacter sphaeroides.

The effects of multiple changes in hydrogen bond interactions between the electron donor, a bacteriochlorophyll dimer, and histidine residues in the reaction center from Rhodobacter sphaeroides have been investigated. Site-directed mutations were designed to add or remove hydrogen bonds between the 2-acetyl groups of the dimer and histidine residues at the symmetry-related sites His-L168 and Ph...

Proton and electron transfer in the acceptor quinone complex of photosynthetic reaction centers from Rhodobacter sphaeroides.

For twenty years the photosynthetic reaction center (RC) has been the premier testing ground for theoretical understanding of electron transfer in aperiodic systems, with special, but not unique, reference to long distance biological electron transport. In addition to the known structure, many of the attributes that make RCs so well suited to studying electron transfer function equally well for...