Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1972 Mar;49(3):381-4.
doi: 10.1104/pp.49.3.381.

Studies on Effect of Certain Quinones: I. Electron Transport, Photophosphorylation, and CO(2) Fixation in Isolated Chloroplasts

Affiliations

Studies on Effect of Certain Quinones: I. Electron Transport, Photophosphorylation, and CO(2) Fixation in Isolated Chloroplasts

H C Sikka et al. Plant Physiol. 1972 Mar.

Abstract

The effect of quinone herbicides and fungicides on photosynthetic reactions in isolated spinach (Spinacia oleracea) chloroplasts was investigated. 2,3-Dichloro-1,4-naphthoquinone (dichlone), 2-amino-3-chloro-1,4-naphthoquinone (06K-quinone), and 2,3,5,6-tetrachloro-1,4-benzoquinone (chloranil) inhibited ferricyanide reduction as well as ATP formation. Benzoquinone had little or no effect on these reactions. The two reactions showed a differential sensitivity to these inhibitors. Dichlone was a strong inhibitor of both photosystems I and II; photosystem I was more sensitive to 06K-quinone than was photosystem II, whereas the reverse was true of chloranil. Chloranil and 06K-quinone inhibited ferricyanide reduction and the coupled photophosphorylation to the same extent, whereas dichlone affected photophosphorylation to a greater extent than the ferricyanide reduction.CO(2) fixation was inhibited by all the quinones to varying degrees. In chloroplasts treated with 06K-quinone or benzoquinone, CO(2) fixation was inhibited to a greater extent than the photoreduction of ferricyanide or ATP formation, indicating the possibility that the two quinones may also inhibit certain reactions in the carbon reduction cycle. The effect of dichlone and chloranil, but not of 06K-quinone, was overcome by the addition of reduced glutathione. The quinones caused an increase in the proportion of (14)C incorporated into 3-phosphoglyceric acid and a reduction in the amount of glycolic acid.

PubMed Disclaimer

References

    1. Biochim Biophys Acta. 1966 Oct 10;126(2):200-6 - PubMed
    1. Plant Physiol. 1970 Apr;45(4):470-4 - PubMed
    1. Proc Natl Acad Sci U S A. 1966 Oct;56(4):1095-101 - PubMed
    1. Biochim Biophys Acta. 1965 Nov 29;109(2):317-31 - PubMed
    1. Plant Physiol. 1969 Aug;44(8):1115-21 - PubMed

LinkOut - more resources