Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect

Krohs U, Metzner H (1990)
Bioelectrochemistry and Bioenergetics 23(2): 141-151.

Download
OA 846.55 KB
Zeitschriftenaufsatz | Veröffentlicht | Englisch
Volltext vorhanden für diesen Nachweis
Autor
;
Abstract / Bemerkung
The overall kinetics of photosystem II was scanned by means of a double flash technique. Oxygen evolution by pea thylakoids provided with an artificial electron acceptor was measured under a regime of double flashes of variant intervals. The pH optimum in H2O lies near p1H 7.2 (p1H meaning the pH in H2O), with a first-order rate constant of 800 s−1 at 20°C. In deuterium oxide (D2O), a plateau of maximum reaction rate was found between p2H 6.6 and 7.8 (p2H meaning the "pH" in D2O), the highest rate constant being 550 s−1. The apparent kinetic deuterium isotope effect is therefore 1.45. Outside this plateau region, there seems to exist another isotope effect of 1.2 to 1.3. These effects are small but may nevertheless reflect the fact that more than one step of the photosystem II reaction sequence is involved in the splitting of a bond to hydrogen. However, the effects may also be solvent effects or located on the acceptor side of the photosystem.
Erscheinungsjahr
Zeitschriftentitel
Bioelectrochemistry and Bioenergetics
Band
23
Zeitschriftennummer
2
Seite
141-151
ISSN
PUB-ID

Zitieren

Krohs U, Metzner H. Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect. Bioelectrochemistry and Bioenergetics. 1990;23(2):141-151.
Krohs, U., & Metzner, H. (1990). Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect. Bioelectrochemistry and Bioenergetics, 23(2), 141-151. doi:10.1016/0302-4598(90)85003-Z
Krohs, U., and Metzner, H. (1990). Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect. Bioelectrochemistry and Bioenergetics 23, 141-151.
Krohs, U., & Metzner, H., 1990. Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect. Bioelectrochemistry and Bioenergetics, 23(2), p 141-151.
U. Krohs and H. Metzner, “Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect”, Bioelectrochemistry and Bioenergetics, vol. 23, 1990, pp. 141-151.
Krohs, U., Metzner, H.: Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect. Bioelectrochemistry and Bioenergetics. 23, 141-151 (1990).
Krohs, Ulrich, and Metzner, Helmut. “Overall kinetics of photosystem II: pH Dependence and deuterium isotope effect”. Bioelectrochemistry and Bioenergetics 23.2 (1990): 141-151.
Alle Dateien verfügbar unter der/den folgenden Lizenz(en):
Copyright Statement:
This Item is protected by copyright and/or related rights. [...]
Volltext(e)
Access Level
OA Open Access
Zuletzt Hochgeladen
2017-12-21T15:53:58Z