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Updated: Aug 15, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
A picosecond circular dichroism study of photosynthetic reaction centers from Rhodobacter sphaeroides
Abstract:
Picosecond transient circular dichroism spectra are reported for the primary intermediates in the photocycle of reaction centers isolated from Rhodobacter sphaeroides. The time-resolved circular dichroism spectra of the two electron transfer intermediates (BChl2) +BPh-LQA and (BChl2) +BPhLQ-A reveal a large, nonconservative, and fairly stationary CD band at 800 nm. These results suggests that mechanisms other than exciton interactions need to be included in order to explain the optical activity of this biological system.
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