Structures of a phycobilisome in light-harvesting and photoprotected states

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F22%3A00568506" target="_blank" >RIV/60077344:_____/22:00568506 - isvavai.cz</a>

Alternative codes found

RIV/60076658:12310/22:43904804

Result on the web

<a href="https://www.nature.com/articles/s41586-022-05156-4" target="_blank" >https://www.nature.com/articles/s41586-022-05156-4</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1038/s41586-022-05156-4" target="_blank" >10.1038/s41586-022-05156-4</a>

Result language

angličtina

Original language name

Structures of a phycobilisome in light-harvesting and photoprotected states

Original language description

Phycobilisome (PBS) structures are elaborate antennae in cyanobacteria and red algae(1,2). These large protein complexes capture incident sunlight and transfer the energy through a network of embedded pigment molecules called bilins to the photosynthetic reaction centres. However, light harvesting must also be balanced against the risks of photodamage. A known mode of photoprotection is mediated by orange carotenoid protein (OCP), which binds to PBS when light intensities are high to mediate photoprotective, non-photochemical quenching(3-6). Here we use cryogenic electron microscopy to solve four structures of the 6.2 MDa PBS, with and without OCP bound, from the model cyanobacterium Synechocystis sp. PCC 6803. The structures contain a previously undescribed linker protein that binds to the membrane-facing side of PBS. For the unquenched PBS, the structures also reveal three different conformational states of the antenna, two previously unknown. The conformational states result from positional switching of two of the rods and may constitute a new mode of regulation of light harvesting. Only one of the three PBS conformations can bind to OCP, which suggests that not every PBS is equally susceptible to non-photochemical quenching. In the OCP-PBS complex, quenching is achieved through the binding of four 34 kDa OCPs organized as two dimers. The complex reveals the structure of the active form of OCP, in which an approximately 60 angstrom displacement of its regulatory carboxy terminal domain occurs. Finally, by combining our structure with spectroscopic properties(7), we elucidate energy transfer pathways within PBS in both the quenched and light-harvesting states. Collectively, our results provide detailed insights into the biophysical underpinnings of the control of cyanobacterial light harvesting. The data also have implications for bioengineering PBS regulation in natural and artificial light-harvesting systems.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10610 - Biophysics

Project

<a href="/en/project/GX19-28323X" target="_blank" >GX19-28323X: Relation between structure and function of carotenoids: New pathways to answer unresolved questions</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Nature

ISSN

0028-0836

e-ISSN

1476-4687

Volume of the periodical

609

Issue of the periodical within the volume

7928

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

835-845

UT code for WoS article

000848083000005

EID of the result in the Scopus database

2-s2.0-85137252739