Inhibition of photosystem II precedes thylakoid membrane lipid peroxidation in bisulfite-treated leaves of Phaseolus vulgaris

Journal Article · Tue Aug 01 00:00:00 EDT 1989 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.90.4.1492· OSTI ID:6603865

Covello, P S; Dumbroff, E B; Thompson, J E ^[1]; Chang, A ^[2]

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1. Univ. of Waterloo, Ontario (Canada) Univ. of Guelph, Ontario (Canada)
2. Univ. of Toronto, Ontario (Canada)

Exposure of leaves to SO{sub 2} bisulfite is known to induce peroxidation of thylakoid lipids and to inhibit photosynthetic electron transport. In the present study, we have examined the temporal relationship between bisulfite-induced thylakoid lipid peroxidation and inhibition of electron transport in an attempt to clarify the primary mechanism of SO{sub 2} phytotoxicity. Primary leaves of bean (Phaseolus vulgaris L. cv Kinghorn) were floated on a solution of NaHSO{sub 3}, and the effects of this treatment on photosynthetic electron transport were determined in vivo by measurements of chlorophyll a fluorescence induction and in vitro by biochemical measurements of the light reactions using isolated thylakoids. Lipid peroxidation in treated leaves was followed by monitoring ethane emission from leaf segments and by measuring changes in fatty acid composition and lipid fluidity in isolated thylakoids. A 1 hour treatment with bisulfite inhibited photosystem II (PSII) activity by 70% without modifying Photosystem I, and this inhibitory effect was not light-dependent. By contrast, lipid peroxidation was not detectable until after the inhibition of PSII and was strongly light dependent. This temporal separation of events together with the differential effect of light suggests that bisulfite-induced inhibition of PSII is not a secondary effect of lipid peroxidation, and that bisulfite acts directly on one or more components of PSII.

• OSTI ID: 6603865
• Journal Information: Plant Physiology; (USA), Vol. 90:4; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
LIPIDS
METABOLISM
PHASEOLUS
PHOTOSYNTHESIS
PHOTOSYNTHETIC REACTION CENTERS
INHIBITION
SULFITES
TOXICITY
SULFUR DIOXIDE
CHLOROPHYLL
ELECTRON TRANSFER
LEAVES
PHOTOSYNTHETIC MEMBRANES
VISIBLE RADIATION
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
LEGUMINOSAE
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MEMBRANES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHYTOCHROMES
PIGMENTS
PLANTS
PORPHYRINS
PROTEINS
RADIATIONS
SULFUR COMPOUNDS
SULFUR OXIDES
SYNTHESIS
560300* - Chemicals Metabolism & Toxicology