Mechanism of Triplet Energy Transfer in Photosynthetic Bacterial Reaction Centers
| Autor: | Joann Williams, Anne-Marie Carey, Neal W. Woodbury, Bing Rong Gao, Joshua Locsin, Su Lin, Sarthak Mandal, James P. Allen |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Photosynthetic reaction centre Dimer Photosynthetic Reaction Center Complex Proteins Rhodobacter sphaeroides 010402 general chemistry Photochemistry 01 natural sciences 03 medical and health sciences chemistry.chemical_compound Electron transfer Ultrafast laser spectroscopy Materials Chemistry Physical and Theoretical Chemistry biology Chemistry Temperature biology.organism_classification 0104 chemical sciences Surfaces Coatings and Films Microsecond Kinetics 030104 developmental biology Energy Transfer Excited state Bacteriochlorophyll |
| Zdroj: | The journal of physical chemistry. B. 121(27) |
| ISSN: | 1520-5207 |
| Popis: | In purple bacterial reaction centers, triplet excitation energy transfer occurs from the primary donor P, a bacteriochlorophyll dimer, to a neighboring carotenoid to prevent photodamage from the generation of reactive oxygen species. The BB bacteriochlorophyll molecule that lies between P and the carotenoid on the inactive electron transfer branch is involved in triplet energy transfer between P and the carotenoid. To expand the high-resolution spectral and kinetic information available for describing the mechanism, we investigated the triplet excited state formation and energy transfer pathways in the reaction center of Rhodobacter sphaeroides using pump–probe transient absorption spectroscopy over a broad spectral region on the nanosecond to microsecond time scale at both room temperature and at 77 K. Wild-type reaction centers were compared with a reaction center mutant (M182HL) in which BB is replaced by a bacteriopheophytin (Φ), as well as to reaction centers that lack the carotenoid. In wild-type re... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|