Abstract
Increasing the solar spectral coverage of native photosynthetic antennas can be achieved using biohybrid light-harvesting (LH) structures comprised of native-like bacterial photosynthetic peptides and synthetic bacteriochlorins with strong near-infrared absorption. Four such biohybrids have been prepared wherein synthetic maleimido-bearing bacteriochlorin BC1-mal is covalently attached to a Cys residue substituted at either the +1, +5 or +11 position (relative to His-0) of the 48-residue β-peptide of Rb. sphaeroides LH1. In addition, a β-peptide with Phe substituted for Tyr at the +4 position along with +1Cys was used to examine possible quenching of the excited BC1 by the Tyr. The β-peptide analogs, as well as their peptide-BC1 conjugates when combined with native α-peptide, and bacteriochlorophyll a (BChl a) self-assemble to form αβ-dyads and therefrom LH1-type cyclic (αβ)n oligomers. Static and time-resolved optical studies show that all of the oligomeric assemblies transfer excitation energy from the appended BC1 to the BChl a array (B875) with an average efficiency of 85 %.
Original language | English (US) |
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Pages (from-to) | 300-313 |
Number of pages | 14 |
Journal | ChemPhotoChem |
Volume | 2 |
Issue number | 3 |
DOIs | |
State | Published - Mar 1 2018 |
Keywords
- bacteriochlorin
- bacteriochlorophyll
- energy transfer
- photosynthetic antennae
- self-assembly
ASJC Scopus subject areas
- Analytical Chemistry
- Physical and Theoretical Chemistry
- Organic Chemistry