Imperial College London

Professor Bill Rutherford FRS

Faculty of Natural SciencesDepartment of Life Sciences

Chair in Biochemistry of Solar Energy
 
 
 
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Contact

 

+44 (0)20 7594 5329a.rutherford Website

 
 
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Location

 

702Sir Ernst Chain BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Takegawa:2019:10.1016/j.bbabio.2019.01.008,
author = {Takegawa, Y and Nakamura, M and Nakamura, S and Noguchi, T and Sellés, J and Rutherford, AW and Boussac, A and Sugiura, M},
doi = {10.1016/j.bbabio.2019.01.008},
journal = {Biochimica et Biophysica Acta - Bioenergetics},
pages = {297--309},
title = {New insights on ChlD1 function in Photosystem II from site-directed mutants of D1/T179 in Thermosynechococcus elongatus},
url = {http://dx.doi.org/10.1016/j.bbabio.2019.01.008},
volume = {1860},
year = {2019}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - The monomeric chlorophyll, ChlD1, which is located between the PD1PD2 chlorophyll pair and the pheophytin, PheoD1, is the longest wavelength chlorophyll in the heart of Photosystem II and is thought to be the primary electron donor. Its central Mg2+ is liganded to a water molecule that is H-bonded to D1/T179. Here, two site-directed mutants, D1/T179H and D1/T179V, were made in the thermophilic cyanobacterium, Thermosynechococcus elongatus, and characterized by a range of biophysical techniques. The Mn4CaO5 cluster in the water-splitting site is fully active in both mutants. Changes in thermoluminescence indicate that i) radiative recombination occurs via the repopulation of ChlD1 itself; ii) non-radiative charge recombination reactions appeared to be faster in the T179H-PSII; and iii) the properties of PD1PD2 were unaffected by this mutation, and consequently iv) the immediate precursor state of the radiative excited state is the ChlD1+PheoD1- radical pair. Chlorophyll bleaching due to high intensity illumination correlated with the amount of 1O2 generated. Comparison of the bleaching spectra with the electrochromic shifts attributed to ChlD1 upon QA- formation, indicates that in the T179H-PSII and in the WT3-PSII, the ChlD1 itself is the chlorophyll that is first damaged by 1O2, whereas in the T179V-PSII a more red chlorophyll is damaged, the identity of which is discussed. Thus, ChlD1 appears to be one of the primary damage site in recombination-mediated photoinhibition. Finally, changes in the absorption of ChlD1 very likely contribute to the well-known electrochromic shifts observed at ~430nm during the S-state cycle.
AU - Takegawa,Y
AU - Nakamura,M
AU - Nakamura,S
AU - Noguchi,T
AU - Sellés,J
AU - Rutherford,AW
AU - Boussac,A
AU - Sugiura,M
DO - 10.1016/j.bbabio.2019.01.008
EP - 309
PY - 2019///
SN - 0005-2728
SP - 297
TI - New insights on ChlD1 function in Photosystem II from site-directed mutants of D1/T179 in Thermosynechococcus elongatus
T2 - Biochimica et Biophysica Acta - Bioenergetics
UR - http://dx.doi.org/10.1016/j.bbabio.2019.01.008
UR - https://www.ncbi.nlm.nih.gov/pubmed/30703365
UR - http://hdl.handle.net/10044/1/67279
VL - 1860
ER -