Global changes of chlorophyll excitonic interactions in photosystem II during thermal denaturation
Qiang Xu1, Xiaolan Ding, Yandao Gong
1State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
Abstract:
Photosystem II (PSII) is a multisubunit chlorophyll-binding enzyme that absorbs light to catalyze water oxidation and plastoquinone reduction. Chlorophyll excitonic interaction changes in PSII were studied by absorption and circular dichroism spectra from 25 degrees C to 80 degrees C, and protein subunit denaturation was monitored by differential scanning calorimetry. A four-stage process of chlorophyll excitonic interaction change was observed being correlated with the denaturation of protein subunits.
More Related Videos
Related Concept Videos
Photosystem II
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
Photosystems
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...
Protein Denaturation
The Photochemical Reaction Center
Photosystem I
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...
Responses to Heat and Cold Stress


