Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Gu, T.-Q.
Right arrow Articles by Fujita, Y.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Gu, T.-Q.
Right arrow Articles by Fujita, Y.
Agricola
Right arrow Articles by Gu, T.-Q.
Right arrow Articles by Fujita, Y.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Plant and Cell Physiology, 1994, Vol. 35, No. 8 1135-1140
© 1994

Changes in the Cytochrome c Oxidase Activity in Response to Light Regime for Photosynthesis Observed with the Cyanophyte Synechocystis PCC 6714

Tian-Qing Gu1, Yumi Iwama, Akio Murakami, Siba Prasad Adhikary2 and Yoshihiko Fujita

Department of Cell Biology, National Institute for Basic Biology Okazaki, Aichi, 444 Japan

Changes in the activity of cytochrome c oxidase (EC 1.9.3.1 [EC] , Cyt-oxidase) in response to growth conditions were studied with the cyanophyte Synechocystis PCC 6714 in relation to changes in PSI abundance induced by light regime for photosynthesis. The activity was determined with the Vmax of mammalian cytochrome c oxidation by isolated membranes. The activity of glucose-6-phosphate (G-6-P):NADP+ oxidoreductase (EC 1.1.1.49 [EC] ) was also determined supplementarily. Cyt-oxidase activity was enhanced by glucose added to the medium even when cell growth maintained mainly by oxygenic photosynthesis. G-6-P:NADP+ oxidoreductase was also activated by glucose. The enhanced level of Cyt-oxidase was higher under PSII light, which causes high PSI abundance, than that under PSI light, which causes low PSI abundance. The level was intermediate under hetetrotrophic conditions. Although the activity level was low in cells grown under autotrophic conditions, the level was again lower in cells grown under PSI light than under PSII light. The change of Cyt-oxidase activity in response to light regime occurred in the same direction as that for the variation of PSI abundance. Results suggest that in Synechocystis PCC 6714, the capacity of electron turnover at the two terminal components of thylakoid electron transport system, Cyt-oxidase and PSI, changes in parallel with each other in response to the state of thylakoid electron transport system.

1Present address: Institute of Botany, Academia Sinica, Beijing 100044, China

2Present address: Department of Botany, Utkal University, Bhubaneswar, India 751004

(Received June 24, 1994; Accepted August 17, 1994)
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.