Inhibition of oxidative phosphorylation and respiration by ozone in tobacco mitochondria

Journal Article · Sun Jan 01 04:00:00 EST 1967 · Plant Physiol.; (United States)

DOI:https://doi.org/10.1104/pp.42.5.691· OSTI ID:5014976

Lee, T T

Ozone was found to inhibit oxidative phosphorylation and oxygen uptake in mitochondria of tobacco leaves (Nicotiana tabacum, L., var. White Gold). The inhibition appeared to occur at both substrate and electron-transport chain levels. The inhibition increased with the length of exposure to ozone, however, the phosphorylative system was more sensitive to ozone than the respiratory system. With mitochondria from detached leaves after being treated with ozone at 1 ppm for l hr, uncoupling of phosphorylation was demonstrated without any detectable change in the rate of respiration in the early stage of ozone effect. Inhibition of phosphorylation by ozone was also demonstrated in isolated mitochondria without apparent change in optical density of the mitochondrial suspension at 520 ..mu..M. Therefore, mitochondrial swelling appears not to be a necessary first step for ozone-induced uncoupling of phosphorylation. The evidence suggests that inhibition of oxidative phosphorylation in mitochondria may be a primary effect of ozone in tobacco leaves. Sucrose and glucose, when fed to the detached tobacco leaves before ozone treatment, tended to raise the phosphorylative activity of mitochondria. Mannitol and lactose were less effective. 12 references, 4 figures, 3 tables.

• Research Organization: Canada Dept. of Agriculture, Delhi, Ontario
• OSTI ID: 5014976
• Journal Information: Plant Physiol.; (United States), Journal Name: Plant Physiol.; (United States) Vol. 42; ISSN PLPHA
• Country of Publication: United States
• Language: English

Related Subjects

560301 -- Chemicals Metabolism & Toxicology-- Cells-- (-1987)
560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
CELL CONSTITUENTS
CHEMICAL REACTIONS
DOSE-RESPONSE RELATIONSHIPS
ELEMENTS
INHIBITION
LEAVES
MITOCHONDRIA
NICOTIANA
NONMETALS
ORGANOIDS
OXYGEN
OZONE
PHOSPHORYLATION
PLANTS
RESPIRATION
UPTAKE