Abstract
Suppression of electron flow (and its subsequent restoration with 3–10 mM NaHCO 3) on the donor side of photosystem II is shown upon either a partial depletion of pea subchloroplast membranes in bicarbonate or the addition of 5–20 μM formate. At higher concentrations (5 mM) formate induces the known ‘bicarbonate effect’ on the acceptor side of photosystem II. In preparations depleted of manganese the restoration of electron flow with 0.1–0.2 μM MnCl 2 (2–4 Mn per photosystem II reaction center) occurs only in the presence of bicarbonate and it is accompanied by an increased functional binding of manganese. Restoration of electron flow with diphenylcarbazide or NH 2OH does not require the addition of NaHCO 3. It is suggested that bicarbonate participates in the formation of the Mn-cluster capable of water oxidation or serves as a substrate for the water-oxidizing center.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
