Photoactivation and Photoinhibition Are Competing in a Mutant of Chlamydomonas reinhardtii Lacking the 23-kDa Extrinsic Subunit of Photosystem II
(1996) In Journal of Biological Chemistry 271(46). p.28918-28924- Abstract
- The process of photoactivation has been studied in dark grown cells of Chlamydomonas reinhardtii. A mutant, FUD 39, lacking the Cl-concentrating 23-kDa psbP protein of photosystem II was found to have a decreased capability to perform photoactivation. The yield of the process never reached wild type level, and contrary to the wild type, it was highly dependent on the intensity of the activating light, with a very narrow optimum around 1 µE m2 s1. The different behavior in the mutant can be explained by a requirement for a longer dark period, between the two photoacts, during the photoactivation. This is proposed to reflect the decreased Cl affinity in the mutant. Photoactivation in the mutant was also found to be very sensitive to... (More)
- The process of photoactivation has been studied in dark grown cells of Chlamydomonas reinhardtii. A mutant, FUD 39, lacking the Cl-concentrating 23-kDa psbP protein of photosystem II was found to have a decreased capability to perform photoactivation. The yield of the process never reached wild type level, and contrary to the wild type, it was highly dependent on the intensity of the activating light, with a very narrow optimum around 1 µE m2 s1. The different behavior in the mutant can be explained by a requirement for a longer dark period, between the two photoacts, during the photoactivation. This is proposed to reflect the decreased Cl affinity in the mutant. Photoactivation in the mutant was also found to be very sensitive to competing photoinhibitory processes. The inhibition was located to the donor side of photosystem II and affected the photoactivation capability before electron transfer from Tyrz was inhibited. We propose an extended model for photoactivation in which an intermediate that is sensitive to photoinhibition is formed if Cl is not functionally bound to the manganese cluster. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/126344
- author
- Rova, E Maria ; Mc Ewen, Birgitta ; Fredriksson, Per-Olof and Styring, Stenbjörn LU
- organization
- publishing date
- 1996
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Biological Chemistry
- volume
- 271
- issue
- 46
- pages
- 28918 - 28924
- publisher
- American Society for Biochemistry and Molecular Biology
- external identifiers
-
- scopus:0029826533
- ISSN
- 1083-351X
- language
- English
- LU publication?
- yes
- id
- bef9c633-79f1-4e0f-93cb-c3a5a0ae3245 (old id 126344)
- alternative location
- http://www.jbc.org/cgi/reprint/271/46/28918
- date added to LUP
- 2016-04-01 11:45:01
- date last changed
- 2022-03-13 00:06:46
@article{bef9c633-79f1-4e0f-93cb-c3a5a0ae3245, abstract = {{The process of photoactivation has been studied in dark grown cells of Chlamydomonas reinhardtii. A mutant, FUD 39, lacking the Cl-concentrating 23-kDa psbP protein of photosystem II was found to have a decreased capability to perform photoactivation. The yield of the process never reached wild type level, and contrary to the wild type, it was highly dependent on the intensity of the activating light, with a very narrow optimum around 1 µE m2 s1. The different behavior in the mutant can be explained by a requirement for a longer dark period, between the two photoacts, during the photoactivation. This is proposed to reflect the decreased Cl affinity in the mutant. Photoactivation in the mutant was also found to be very sensitive to competing photoinhibitory processes. The inhibition was located to the donor side of photosystem II and affected the photoactivation capability before electron transfer from Tyrz was inhibited. We propose an extended model for photoactivation in which an intermediate that is sensitive to photoinhibition is formed if Cl is not functionally bound to the manganese cluster.}}, author = {{Rova, E Maria and Mc Ewen, Birgitta and Fredriksson, Per-Olof and Styring, Stenbjörn}}, issn = {{1083-351X}}, language = {{eng}}, number = {{46}}, pages = {{28918--28924}}, publisher = {{American Society for Biochemistry and Molecular Biology}}, series = {{Journal of Biological Chemistry}}, title = {{Photoactivation and Photoinhibition Are Competing in a Mutant of Chlamydomonas reinhardtii Lacking the 23-kDa Extrinsic Subunit of Photosystem II}}, url = {{http://www.jbc.org/cgi/reprint/271/46/28918}}, volume = {{271}}, year = {{1996}}, }