Optically detected magnetic resonance and mutational analysis reveal significant differences in the photochemistry and structure of chlorophyll f synthase and photosystem II

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F23%3A00583746" target="_blank" >RIV/60077344:_____/23:00583746 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0005272823000488?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0005272823000488?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.bbabio.2023.149002" target="_blank" >10.1016/j.bbabio.2023.149002</a>

Result language

angličtina

Original language name

Optically detected magnetic resonance and mutational analysis reveal significant differences in the photochemistry and structure of chlorophyll f synthase and photosystem II

Original language description

In cyanobacteria that undergo far red light photoacclimation (FaRLiP), chlorophyll (Chl) f is produced by the ChlF synthase enzyme, probably by photo-oxidation of Chl a. The enzyme forms homodimeric complexes and the primary amino acid sequence of ChlF shows a high degree of homology with the D1 subunit of photosystem II (PSII). However, few details of the photochemistry of ChlF are known. The results of a mutational analysis and optically detected magnetic resonance (ODMR) data from ChlF are presented. Both sets of data show that there are significant differences in the photochemistry of ChlF and PSII. Mutation of residues that would disrupt the donor side primary electron transfer pathway in PSII do not inhibit the production of Chl f, while alteration of the putative ChlZ, P680 and QA binding sites rendered ChlF non-functional. Together with previously published transient EPR and flash photolysis data, the ODMR data show that in untreated ChlF samples, the triplet state of P680 formed by intersystem crossing is the primary species generated by light excitation. This is in contrast to PSII, in which 3P680 is only formed by charge recombination when the quinone acceptors are removed or chemically reduced. The triplet states of a carotenoid (3Car) and a small amount of 3Chl f are also observed by ODMR. The polarization pattern of 3Car is consistent with its formation by triplet energy transfer from ChlZ if the carotenoid molecule is rotated by 15 degrees about its long axis compared to the orientation in PSII. It is proposed that the singlet oxygen formed by the interaction between molecular oxygen and 3P680 might be involved in the oxidation of Chl a to Chl f.

Czech name

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Czech description

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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/EF18_053%2F0016982" target="_blank" >EF18_053/0016982: International mobilities for researchers and administrative employees of Biology Centre</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

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

Name of the periodical

Biochimica Et Biophysica Acta-Bioenergetics

ISSN

0005-2728

e-ISSN

1879-2650

Volume of the periodical

1864

Issue of the periodical within the volume

4

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

9

Pages from-to

149002

UT code for WoS article

001102522300001

EID of the result in the Scopus database

2-s2.0-85167832912