scholarly journals The Thylakoid Lumen Protease Deg1 Is Involved in the Repair of Photosystem II from Photoinhibition in Arabidopsis

2007 ◽  
Vol 19 (3) ◽  
pp. 1039-1047 ◽  
Author(s):  
Einat Kapri-Pardes ◽  
Leah Naveh ◽  
Zach Adam
Keyword(s):  
Photosystem Ii ◽  
Thylakoid Lumen

scholarly journals Proximity-based proteomics reveals the thylakoid lumen proteome in the cyanobacterium Synechococcus sp. PCC 7002

2020 ◽  
Author(s):  
Kelsey K. Dahlgren ◽  
Colin Gates ◽  
Thomas Lee ◽  
Jeffrey C. Cameron
Keyword(s):  
Photosystem Ii ◽  
Cell Biology ◽  
Region Of Interest ◽  
Protein Labeling ◽  
Spatiotemporal Resolution ◽  
Thylakoid Lumen ◽  
Conventional Fractionation ◽  
Great Progress ◽  
Biochemical Fractionation ◽  
Synechococcus Sp

AbstractCyanobacteria possess unique intracellular organization. Many proteomic studies have examined different features of cyanobacteria to learn about the intracellular structures and their respective functions. While these studies have made great progress in understanding cyanobacterial physiology, the conventional fractionation methods used to purify cellular structures have limitations; specifically, certain regions of cells cannot be purified with existing fractionation methods. Proximity-based proteomics techniques were developed to overcome the limitations of biochemical fractionation for proteomics. Proximity-based proteomics relies on spatiotemporal protein labeling followed by mass spectrometry of the labeled proteins to determine the proteome of the region of interest. We performed proximity-based proteomics in the cyanobacterium Synechococcus sp. PCC 7002 with the APEX2 enzyme, an engineered ascorbate peroxidase. We determined the proteome of the thylakoid lumen, a region of the cell that has remained challenging to study with existing methods, using a translational fusion between APEX2 and PsbU, a lumenal subunit of photosystem II. Our results demonstrate the power of APEX2 as a tool to study the cell biology of intracellular features and processes, including photosystem II assembly in cyanobacteria, with enhanced spatiotemporal resolution.

scholarly journals TLP18.3, a novel thylakoid lumen protein regulating photosystem II repair cycle

2007 ◽  
Vol 406 (3) ◽  
pp. 415-425 ◽  
Author(s):  
Sari Sirpiö ◽  
Yagut Allahverdiyeva ◽  
Marjaana Suorsa ◽  
Virpi Paakkarinen ◽  
Julia Vainonen ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
Protein Complexes ◽  
D1 Protein ◽  
Proteome Analysis ◽  
Growth Conditions ◽  
Dual Function ◽  
High Turnover ◽  
Thylakoid Lumen ◽  
Chain Complexes ◽  
Nascent Chain

A proteome analysis of Arabidopsis thaliana thylakoid-associated polysome nascent chain complexes was performed to find novel proteins involved in the biogenesis, maintenance and turnover of thylakoid protein complexes, in particular the PSII (photosystem II) complex, which exhibits a high turnover rate. Four unknown proteins were identified, of which TLP18.3 (thylakoid lumen protein of 18.3 kDa) was selected for further analysis. The Arabidopsis mutants (SALK_109618 and GABI-Kat 459D12) lacking the TLP18.3 protein showed higher susceptibility of PSII to photoinhibition. The increased susceptibility of ΔTLP18.3 plants to high light probably originates from an inefficient reassembly of PSII monomers into dimers in the grana stacks, as well as from an impaired turnover of the D1 protein in stroma exposed thylakoids. Such dual function of the TLP18.3 protein is in accordance with its even distribution between the grana and stroma thylakoids. Notably, the lack of the TLP18.3 protein does not lead to a severe collapse of the PSII complexes, suggesting a redundancy of proteins assisting these particular repair steps to assure functional PSII. The ΔTLP18.3 plants showed no clear visual phenotype under standard growth conditions, but when challenged by fluctuating light during growth, the retarded growth of ΔTLP18.3 plants was evident.

scholarly journals Photosystem II Repair and Plant Immunity: Lessons Learned from Arabidopsis Mutant Lacking the THYLAKOID LUMEN PROTEIN 18.3

2016 ◽  
Vol 7 ◽  
Author(s):  
Sari Järvi ◽  
Janne Isojärvi ◽  
Saijaliisa Kangasjärvi ◽  
Jarkko Salojärvi ◽  
Fikret Mamedov ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
Plant Immunity ◽  
Lessons Learned ◽  
Thylakoid Lumen ◽  
Arabidopsis Mutant ◽  
Photosystem Ii Repair

Characterization of photosystem II with the atomic-force microscope

1992 ◽  
Vol 50 (2) ◽  
pp. 1146-1147
Author(s):  
Kathleen M. Marr ◽  
Mary K. Lyon
Keyword(s):  
Photosystem Ii ◽  
Atomic Force Microscope ◽  
Three Dimensional ◽  
Biologically Active ◽  
Atomic Force ◽  
Freeze Etching ◽  
Image Averaging ◽  
Oxygen Evolving ◽  
Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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