Heterogeneity among photosystem I

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Thylakoids from spinach were sonicated and separated by aqueous two-phase partitioning into two vesicle populations originating from grana (α vesicles) and stroma lamellae (β vesicles), respectively, according to a procedure described earlier (Andreasson et al. (1988) Biochim. Biophys. Acta 936, 339–350). The functional antenna sizes of Photosystem I for these two vesicle populations were determined by measuring the kinetics of the photooxidation of P700. Under green light illumination, the antenna size of Photosystem I of the α vesicles (PSIα) was 40% larger (40% larger rate constant of photooxidation) than that of Photosystem I of the β vesicles (PSIβ). By using actinic light, which is preferentially absorbed by chlorophyll b, this difference was accentuated (60%) indicating that the antenna of PSIα contains relatively more chlorophyll b. The experiments did not support the possibility that this difference in functional antenna size was due to ‘spill over’ from Photosystem II. A model is presented which shows that PSIα is located in the periphery of the grana and PSIβ in the stroma lamellae.

References (24)

  • MauzerallD. et al.

    Biochim. Biophys. Acta

    (1989)
  • MelisA. et al.

    Biochim. Biophys. Acta

    (1983)
  • LeongT.-Y. et al.

    Biochem. Biophys. Acta

    (1983)
  • MelisA. et al.

    Arch. Biochem. Biophys.

    (1978)
  • AlbertssonP.-A. et al.

    Biochim. Biophys. Acta

    (1988)
  • AlbertssonP.-Å. et al.

    Biochim. Biophys. Acta

    (1990)
  • AndreassonE. et al.

    Biochim. Biophys. Acta

    (1988)
  • MelisA.

    Arch. Biochem. Biophys.

    (1982)
  • OuitrakulR. et al.

    Biochim. Biophys. Acta

    (1973)
  • MelisA. et al.

    Biochim. Biophys Acta

    (1980)
  • WilliamsR.S. et al.

    FEBS Lett.

    (1987)
  • AnderssonB. et al.

    Biochim. Biophys. Acta

    (1980)
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      Therefore, our data allowed calculation of the antenna size of the two photosystems in the following way. It is known from earlier studies [8,37] that the antennae size of PSI in the grana (NI for PSIα) is about 40% larger, i.e. 300. That the antennae of PSI in the grana (PSIα) is larger than PSI in the stroma lamellae (PSIβ) is a result of attachment of LHCII trimers (Lhcb,1,2) to PSIβ.

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