This title appears in the Scientific Report :
2023
Please use the identifier:
http://dx.doi.org/10.1073/pnas.2221595120 in citations.
Please use the identifier: http://dx.doi.org/10.34734/FZJ-2023-03522 in citations.
DNA-binding and protein structure of nuclear factors likely acting in genetic information processing in the Paulinella chromatophore
DNA-binding and protein structure of nuclear factors likely acting in genetic information processing in the Paulinella chromatophore
The chromatophores in Paulinella are evolutionary-early-stage photosynthetic organelles. Biological processes in chromatophores depend on a combination of chromatophore and nucleus-encoded proteins. Interestingly, besides proteins carrying chromatophore-targeting signals, a large arsenal of short ch...
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Personal Name(s): | Macorano, Luis |
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Binny, Taniya M. / Spiegl, Tobias / Klimenko, Victoria / Singer, Anna / Oberleitner, Linda / Applegate, Violetta / Seyffert, Sarah / Stefanski, Anja / Gremer, Lothar / Gertzen, Christoph G. W. / Höppner, Astrid / Smits, Sander H. J. / Nowack, Eva C. M. (Corresponding author) | |
Contributing Institute: |
Strukturbiochemie; IBI-7 |
Published in: | Proceedings of the National Academy of Sciences of the United States of America, 120 (2023) 27, S. e2221595120 |
Imprint: |
Washington, DC
National Acad. of Sciences
2023
|
DOI: |
10.1073/pnas.2221595120 |
DOI: |
10.34734/FZJ-2023-03522 |
Document Type: |
Journal Article |
Research Program: |
Erforschung der Kontaktzone zwischen Wirtszelle und ihren neu erworbenen photosynthetischen Organellen in der Amöbe Paulinella chromatophora (Rhizaria, Cercozoa) (B09) Molecular Information Processing in Cellular Systems |
Link: |
OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.34734/FZJ-2023-03522 in citations.
The chromatophores in Paulinella are evolutionary-early-stage photosynthetic organelles. Biological processes in chromatophores depend on a combination of chromatophore and nucleus-encoded proteins. Interestingly, besides proteins carrying chromatophore-targeting signals, a large arsenal of short chromatophore-targeted proteins (sCTPs; <90 amino acids) without recognizable targeting signals were found in chromatophores. This situation resembles endosymbionts in plants and insects that are manipulated by host-derived antimicrobial peptides. Previously, we identified an expanded family of sCTPs of unknown function, named here "DNA-binding (DB)-sCTPs". DB-sCTPs contain a ~45 amino acid motif that is conserved in some bacterial proteins with predicted functions in DNA processing. Here, we explored antimicrobial activity, DNA-binding capacity, and structures of three purified recombinant DB-sCTPs. All three proteins exhibited antimicrobial activity against bacteria involving membrane permeabilization, and bound to bacterial lipids in vitro. A combination of in vitro assays demonstrated binding of recombinant DB-sCTPs to chromatophore-derived genomic DNA sequences with an affinity in the low nM range. Additionally, we report the 1.2 Å crystal structure of one DB-sCTP. In silico docking studies suggest that helix α2 inserts into the DNA major grove and the exposed residues, that are highly variable between different DB-sCTPs, confer interaction with the DNA bases. Identification of photosystem II subunit CP43 as a potential interaction partner of one DB-sCTP, suggests DB-sCTPs to be involved in more complex regulatory mechanisms. We hypothesize that membrane binding of DB-sCTPs is related to their import into chromatophores. Once inside, they interact with the chromatophore genome potentially providing nuclear control over genetic information processing. |