Related Experiment Video
Updated: Jun 27, 2026
03:54
Observation of Photobehavior in Chlamydomonas reinhardtii
Published on: May 6, 2022
TEF8 regulates H2 photoproduction by destabilizing PSII supercomplexes in Chlamydomonas
Xiaoyu Wang1,2, Qiang Yao1,2, Xiaohan Chang1,2
1College of Life Sciences, Northwest University, 710069, Xi'an, People's Republic of China.
The Plant Journal : for Cell and Molecular Biology
|June 25, 2026
Summary
Green microalgae can produce hydrogen for renewable energy. A new study reveals TEF8 negatively regulates this process by degrading photosystem II (PSII), hindering electron supply for hydrogen production.
Area of Science:
- * Photosynthesis and renewable energy research.
- * Molecular regulation of algal hydrogen photoproduction.
Background:
- * Hydrogen (H2) photoproduction by microalgae is a promising renewable energy source.
- * Efficiency is limited by oxygen sensitivity of hydrogenases and photosystem II (PSII) electron supply.
- * Sulfur deprivation, a common method to induce H2 production, downregulates PSII and restricts electron flow.
Purpose of the Study:
- * To investigate the role of Thylakoid Enriched Fraction 8 (TEF8) in regulating H2 photoproduction in *Chlamydomonas reinhardtii* under sulfur deprivation.
- * To identify TEF8 as a potential target for enhancing algal H2 production.
Main Methods:
- * Generation and analysis of *tef8* knockout mutants in *Chlamydomonas reinhardtii*.
- * Measurement of H2 evolution rates under induced H2 photoproduction conditions.
- * Biochemical assays to assess PSII supercomplex stability and subunit dephosphorylation.
Main Results:
- * The *tef8* knockout mutant showed significantly enhanced H2 evolution compared to wild type.
- * PSII supercomplexes were more stable in the *tef8* mutant under sulfur deprivation.
- * TEF8 dephosphorylates PSII subunits, promoting PSII core complex degradation; loss of TEF8 function stabilizes PSII.
Conclusions:
- * TEF8 acts as a negative regulator of H2 photoproduction by modulating PSII activity.
- * Impairing TEF8 function stabilizes PSII, maintaining electron flux to hydrogenases and enhancing H2 production.
- * Targeting TEF8 offers a strategy to improve the efficiency of renewable hydrogen energy from microalgae.
More Related Videos
11:10Protein-protein Interactions Visualized by Bimolecular Fluorescence Complementation in Tobacco Protoplasts and Leaves
Published on: March 9, 2014
08:04A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
Related Concept Videos
01:22Photosystem II
The multi-protein complex photosystem II (PS II) harvests photons and transfers their energy through its bound pigments to its reaction center, and ultimately to photosystem I (PSI) through the electron transport chain. The pigments responsible for caputirng the light energy in photosystems include chlorophyll a, chlorophyll b, and carotenoids.
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
01:32Photosystems
Photosystems are multiprotein complexes that form the functional units of photosynthesis in plants, algae, and cyanobacteria. They are found embedded in the membrane of tiny sac-like structures called thylakoids placed inside the chloroplast.
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
01:27Photosystem I
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
01:29The Photochemical Reaction Center
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
01:22Protein Transport to the Thylakoids
Thylakoids are membrane-bound sac-like structures within the chloroplast that serve as sites for photosynthesis. Thylakoid lumen contains many electron transport proteins and is enclosed by a thylakoid membrane rich in the light-harvesting complex. Proteins targeted to the thylakoids are transported as precursors and are sorted by the general TOC/TIC import pathway. Once the precursor reaches the stroma, stromal processing peptidases remove their transit signal and expose thylakoid signal...
01:24Protein Transport to the Stroma
Chloroplasts are triple membrane structures with an outer membrane, an inner membrane, and a thylakoid membrane, each containing distinct metabolite transporters, membrane translocons, and enzymes. Appropriate sorting and translocating these proteins to their correct membrane systems is essential for chloroplast function.
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...