Tools
ToolsSwainsbury, David J. K., Qian, Pu, Hitchcock, Andrew and Hunter, C. Neil (2023) The structure and assembly of reaction centre-light-harvesting 1 complexes in photosynthetic bacteria. Bioscience Reports, 43 (5). ISSN 0144-8463
Preview |
PDF (bsr-2022-0089c)
- Published Version
Available under License Creative Commons Attribution. Download (17MB) | Preview |
Abstract
Chlorophototrophic organisms have a charge-separating reaction centre (RC) complex that receives energy from a dedicated light-harvesting (LH) antenna. In the purple phototrophic bacteria, these two functions are embodied by the ‘core’ photosynthetic component, the RC-LH1 complex. RC-LH1 complexes sit within a membrane bilayer, with the central RC wholly or partly surrounded by a curved array of LH1 subunits that bind a series of bacteriochlorophyll (BChl) and carotenoid pigments. Decades of research have shown that the absorption of light initiates a cascade of energy, electron, and proton transfers that culminate in the formation of a quinol, which is subsequently oxidized by the cytochrome bc1 complex. However, a full understanding of all these processes, from femtosecond absorption of light to millisecond quinone diffusion, requires a level of molecular detail that was lacking until the remarkable recent upsurge in the availability of RC-LH1 structures. Here, we survey 13 recently determined RC-LH1 assemblies, and we compare the precise molecular arrangements of pigments and proteins that allow efficient light absorption and the transfer of energy, electrons and protons. We highlight shared structural features, as well as differences that span the bound pigments and cofactors, the structures of individual subunits, the overall architecture of the complexes, and the roles of additional subunits newly identified in just one or a few species. We discuss RC-LH1 structures in the context of prior biochemical and spectroscopic investigations, which together enhance our understanding of the molecular mechanisms of photosynthesis in the purple phototrophic bacteria. A particular emphasis is placed on how the remarkable and unexpected structural diversity in RC-LH1 complexes demonstrates different evolutionary solutions for maximising pigment density for optimised light harvesting, whilst balancing the requirement for efficient quinone diffusion between RC and cytochrome bc1 complexes through the encircling LH1 complex.
| Item Type: | Article |
|---|---|
| Additional Information: | Funding Information: D.J.K.S. and C.N.H were supported by European Research Council (ERC) Synergy Award 854126. D.J.K.S was also supported by the University of East Anglia new investigator start-up funding. A.H. acknowledges support from a Royal Society University Research Fellowship (award number URF\R1\191548). |
| Faculty \ School: | Faculty of Science > School of Biological Sciences |
| UEA Research Groups: | Faculty of Science > Research Groups > Molecular Microbiology |
| Related URLs: | |
| Depositing User: | LivePure Connector |
| Date Deposited: | 12 Sep 2024 12:30 |
| Last Modified: | 25 Sep 2024 18:09 |
| URI: | https://ueaeprints.uea.ac.uk/id/eprint/96739 |
| DOI: | 10.1042/BSR20220089 |
Downloads
Downloads per month over past year
Actions (login required)
 |
View Item |