Third site of proton translocation in green plant photosynthetic electron transport

Journal Article · Fri Dec 01 04:00:00 EST 1978 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.75.12.6031· OSTI ID:5613849

Velthuys, B R

Prereduction of the intersystem pool in isolated spinach chloroplasts leads to the appearance of a slow phase in the field-indicating 515-nm change induced by a flash. Measurements with the pH-indicator dye cresol red show that a proton uptake is associated with this slow 515-nm change. When water is the electron donor to photosystem II, electron transfer to ferricyanide is associated with the uptake of more than one proton per electron. Tetraphenylboron upon oxidation by system II releases a proton directly into the medium; yet, flash-induced electron transport from tetraphenylboron to ferricyanide is accompanied by a net uptake of protons from the medium. The above four results demonstrate the existence of two proton translocation sites in the chain between the two photoacts; the first two observations locate the new site at the oxidizing side of the plastoquinone pool.

• Research Organization: Martin Marietta Labs., Baltimore, MD
• OSTI ID: 5613849
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 75:12; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
CELL CONSTITUENTS
CHARGED-PARTICLE TRANSPORT
CHEMICAL REACTIONS
CHLOROPLASTS
COMPLEXES
DYES
ELECTROMAGNETIC RADIATION
ELECTRON TRANSFER
FERRICYANIDES
FOOD
IRON COMPLEXES
OXIDATION
PHOSPHORYLATION
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANTS
PROTON TRANSPORT
RADIATION TRANSPORT
RADIATIONS
SPINACH
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
TRANSLOCATION
VEGETABLES
VISIBLE RADIATION