Positive correlation between superoxide dismutase and resistance to paraquat toxicity in the green alga Chlorella sorokiniana

Haim D. Rabinowitch, Debra A. Clare, James D. Crapo, Irwin Fridovich*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

53 Scopus citations

Abstract

Paraquat (10-30 μm) exerted a dose-dependent and light-dependent toxicity on Chlorella sorokiniana. Paraquat was also seen to increase the superoxide dismutase content of these cells and to cause the appearance of a new electrophoretically distinct isozyme. Cells grown in the absence of paraquat contained one manganese-superoxide dismutase and two iron-superoxide dismutases, while the paraquat-grown cells contained an additional manganese-superoxide dismutase. Cells which were grown in the presence of 25 μm Paraquat, and which therefore possessed elevated levels of superoxide dismutase, were resistant to 30 μm Paraquat, whereas control cells were bleached and killed by this level of Paraquat. Electron micrography and chemical analysis revealed that Paraquat decreased the starch content of the cells and caused a failure of dividing cells to separate. It appears that Paraquat increases the photoproduction of O2- in C. sorokiniana and that an increase in the cell content of superoxide dismutase is an adaptive response which provides protection against this herbicide.

Original languageEnglish
Pages (from-to)640-648
Number of pages9
JournalArchives of Biochemistry and Biophysics
Volume225
Issue number2
DOIs
StatePublished - Sep 1983

Fingerprint

Dive into the research topics of 'Positive correlation between superoxide dismutase and resistance to paraquat toxicity in the green alga Chlorella sorokiniana'. Together they form a unique fingerprint.

Cite this