Abstract
Enhancing the light-harvesting potential of antenna components in a system of solar energy conversion is an important topic in the field of artificial photosynthesis. We constructed a biohybrid light-harvesting complex 2 (LH2) engineered from Rhodobacter sphaeroides IL106 strain. An artificial fluorophore Alexa Fluor 647 maleimide (A647) was attached to the LH2 bearing cysteine residue at the N-terminal region (LH2-NC) near B800 bacteriochlorophyll a (BChl) assembly. The A647-attached LH2-NC conjugate (LH2-NC-A647) preserved the integrity of the intrinsic chromophores, B800- and B850-BChls, and carotenoids. Femtosecond transient absorption spectroscopy revealed that the sequential energy transfer A647 → B800 → B850 occurs at time scale of 9-10ps with monoexponential dynamics in micellar and lipid bilayer systems. A B800-removed conjugate (LH2-NC[B800(-)]-A647) exhibited a significant decrease in energy transfer efficiency in the micellar system; however, surprisingly, direct energy transfer from A647 to B850 was observed at a rate comparable to that for LH2-NC-A647. This result implies that the energy transfer pathway is modified after B800 removal. The results obtained suggested that a LH2 complex is a potential platform for construction of biohybrid light-harvesting materials with simple energy transfer dynamics through the site-selective attachment of the external antennae and the modifiable energy-funnelling pathway.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.