umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Three-dimensional structure of the Photosystem II assembly factor HCF136 from Arabidopsis thaliana
Umeå University, Faculty of Science and Technology, Department of Chemistry. (Uwe Sauer)
Show others and affiliations
(English)Manuscript (preprint) (Other academic)
National Category
Structural Biology
Identifiers
URN: urn:nbn:se:umu:diva-144011OAI: oai:DiVA.org:umu-144011DiVA, id: diva2:1175131
Available from: 2018-01-17 Created: 2018-01-17 Last updated: 2018-06-09Bibliographically approved
In thesis
1. Structural biology studies of thylakoid lumen proteins required for photosystem II assembly and function
Open this publication in new window or tab >>Structural biology studies of thylakoid lumen proteins required for photosystem II assembly and function
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Little is known about the structures and functions of thylakoid lumen proteins. However, some of these proteins have an essential role in photosynthesis. Photosystem II (PSII) complexes are embedded in the thylakoid membrane of oxygenic photosynthetic organisms and one of the central subunits, the D1 protein, is damaged by light during the light driven water – splitting reaction and must be replaced frequently. One of the thylakoid lumen proteins that is essential for assembly and renewal of PSII complexes is the High Chlorophyll Fluorescence 136 (HCF136) protein. Another important protein for the PSII complex assembly is the Low PSII Accumulation Protein 19 (LPA19). Both proteins, HCF136 and LPA19, were shown to bind to the core subunits of the PSII complex from the lumenal side and LPA19 has been shown to explicitly interact with the soluble C-terminus of the D1 protein, one of the core PSII complex proteins. Prior to the replacement of the damaged D1 protein, the PSII complex needs to be disassembled, which is done with the help of the Maintenance of Photosystem II under High light 2 (MPH2) protein. MPH2, also called TL16, is required during the repair cycle of the PSII complex particularly under increased and fluctuating light conditions.

In this work I have determined the three-dimensional X-ray structures of the HCF136 protein at 1.6 Å resolution and the LPA19 protein at 1.2 Å resolution and have also biochemically analyzed possible interactions of HCF136 with the C-termini of D1 protein. In addition, we have determined the NMR structure of the MPH2 protein.

The protein structures of HCF136, LPA19, and MPH2 determined from A. thaliana provide us with a starting point for further studies to improve our understanding of their functional roles in the assembly, maintenance, disassembly and renewal of the PSII complex. The structures are revealing the molecular details that are particularly important during the design of mutations to study protein-protein interactions and the binding of co-factors.

Furthermore, I have contributed to the characterization of AnPrx6, the 1-Cyx peroxiredoxin from Anabaena sp. 7120. Peroxiredoxins are important caretakers of reactive oxygen species and a homolog PrxQ in A.thaliana is found in the thylakoid lumen. The dimeric AnPrx6 protein revealed different active site residues conformations in each of the dimers, which is probably coupled to its enzymatic activity. Unexpectedly, the protein acted also as a chaperone and showed chaperone activity in its dimeric state, which is a novelty for Prx proteins.

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2018. p. 48
Keywords
structural biology, x-ray crystallography, cloning, protein expression, HCF136, LPA19, MPH2, Prx6, photosynthesis, thylakoid lumen PSII
National Category
Structural Biology
Identifiers
urn:nbn:se:umu:diva-144016 (URN)978-91-7601-807-1 (ISBN)
Public defence
2018-02-05, N430, Naturvetarhuset, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2018-01-22 Created: 2018-01-17 Last updated: 2018-06-09Bibliographically approved

Open Access in DiVA

No full text in DiVA

Authority records BETA

Locmelis, Roland

Search in DiVA

By author/editor
Locmelis, Roland
By organisation
Department of Chemistry
Structural Biology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 50 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf