ATP‐induced photochemical quenching of variable chlorophyll fluorescence

FEBS Letters

Schreiber, U.¹  Rienits, K.G.¹ 

[1] Lehrstuhl Botanik I, Universität Würzburg, Mittlerer Dallenbergweg 64, D-8700 Würzburg, FRG

关键词: Chlorophyll fluorescence;    Photosystem II;    Coupling factor;    ATP hydrolysis;    Cytochrome b-559;    PS I and II;    photosystem I and II;    CF0 and CF1;    subunits of the thylakoid coupling factor;    TNBT;    tri-n-butyl-tin;    DCCD;    dicyclohexylcarbodiimide;    DCMU;    dichlorophenyldimethylurea;   

DOI  :  10.1016/0014-5793(87)81282-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

ATP induces rapid quenching of fluorescence yield in light-activated class D chloroplasts, distinguishable from the slower quenching caused by protein phosphorylation. The mechanism of the rapid quenching is shown to be photochemical, by application of the saturation pulse method with a modulated measuring system [(1986) Photosynth. Res. 10, 51-62]. The effect is most pronounced at relatively low light intensities (optimum 2 ) without addition of electron acceptors. The properties of the ATP-induced quenching with respect to ionophores, uncouplers and ATPase inhibitors suggest involvement of the reversible, light-activated thylakoid ATPase. As a working hypothesis, it is proposed that part of PS II reaction centers, which are stroma-exposed and in close proximity to CF₀-CF₁, are modified by ATPase activity. Transformation of cytochrome b-559 high-potential form to low-potential form by membrane acidification is discussed as a possible mechanism.

【 授权许可】

Unknown