|
|
||||||||
|
Plant Physiology 65:691-696 (1980) © 1980 American Society of Plant Biologists Dependence of Delayed Luminescence upon Adenosine Triphosphatase Activity in Chlorella1,2Institut de Biologie Physico-Chimique, 13, rue Pierre et Marie Curie, 75005, Paris, France
Delayed luminescence and fluorescence yield after illumination by a short flash were measured in Chlorella pyrenoidosa in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Addition of tri-N-butyl-tin (TNBT), a specific inhibitor of ATPase, drastically increases the life-time of the reduced photosystem II primary acceptor Q and decreases the intensity of delayed luminescence. This indicates a slowing of the charge recombination between the oxidized donor and reduced acceptor of photosystem II centers. No inhibition is observed in isolated chloroplasts when the membrane is permeable to ions, i.e. in the presence of Gramicidin D and KCl. It is suggested that there exists in dark-adapted algae a permanent proton gradient which stimulates the charge recombination process. This proton gradient results from the hydrolysis of a pool of ATP by membrane-bound ATPases and collapses after the addition of TNBT. The long lifetime of this proton gradient (several hours) indicates that the ATP probably comes from the mitochondria. The rate of the back reaction occurring from state S3 (as defined by Kok, Forbush, and McGloin 1970 Photochem Photobiol 11: 457-475) is more dependent upon the pH gradient than for state S2.
1 Supported by Centre National de la Recherche Scientifique ER 016, and Contrat No. 015-76 ESF of the Commission of the European Communities. 2 This article is dedicated to the memory of Bessel Kok, in grateful recognition of the happy time we spent in his laboratory, and for the animated and fruitful discussions which we shared with him over the years. This article has been cited by other articles:
|
|||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ASPB Publications | PLANT PHYSIOLOGY® | THE PLANT CELL | |
|---|---|---|---|