Contrôle et dynamisme des changements de l'empilement thylacoïdien et de la fluorescence de la chlorophylle

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Influence of structural and physical properties of the thylakoid membrane on QA- oxidation

Using isolated pea thylakoids, the relative rate of QA- oxidation has been estimated under various conditions, from the restoration of the induction curves following a dark period and from light 1-induced changes in modulated chlorophyll fluorescence excited by light 2. Alterations of QinfAsup-oxidation rates were observed under conditions which affected the degree of thylakoid stacking, the lipid fluidity and the integrity of the membranes. The results are discussed in terms of the interactions between QA- and the plastoquinone pool with particular emphasis on lateral diffusion. © 1985 Martinus Nijhoff/Dr W. Junk Publishers.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

ATP-induced quenching of chlorophyll fluorescence in chloroplasts of higher plants. Dependence on structural properties of the membranes

The ATP-induced quenching of chlorophyll fluorescence in chloroplasts of higher plants is shown to be inhibited when the mobility of the protein complexes into the thylakoid membranes is reduced. Its occurrence also requires the presence of LHC complexes and the ability of the membranes to unstack. These observations, in addition to a slight increase of charge density of the surface-as indicated by 9-aminoacridine fluorescence and high salt-induced chlorophyll fluorescence studies-and partial unstacking of the membranes-as monitored by digitonin method and 540 nm light scattering changes-after phosphorylation, suggest that the ATP-induced quenching of chlorophyll fluorescence could reflect some lateral redistribution of membrane proteins in the lipid matrix of the thylakoids. © 1983 Martinus Nijhoff/Dr W. Junk Publishers.SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe