skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana

Abstract

Earlier studies with Arabidopsis thaliana exposed to ultraviolet B (UV-B) and ozone (O{sub 3}) have indicated the differential responses of superoxide dismutase and glutathione reductase. In this study, we have investigated whether A. thaliana genotype Landsberg erecta and its flavonoid-deficient mutant transparent testa (tt5) is capable of metabolizing UV-B- and O{sub 3}-induced activated oxygen species by invoking similar antioxidant enzymes. UV-B exposure preferentially enhanced guaiacol-peroxidases, ascorbate peroxidase, and peroxidases specific to coniferyl alcohol and modified the substrate affinity of ascorbate peroxidase. O{sub 3} exposure enhanced superoxide dismutase, peroxidases, glutathione reductase, and ascorbate peroxidase to a similar degree and modified the substrate affinity of both glutathione reductase and ascorbate peroxidase. Both UV-B and O{sub 3} exposure enhanced similar Cu,Zn-superoxide dismutase isoforms. New isoforms of peroxidases and ascorbate peroxidase were synthesized in tt5 plants irradiated with UV-B. UV-B radiation, in contrast to O{sub 3}, enhanced the activation oxygen species by increasing membrane-localized NADPH-oxidase activity and decreasing catalase activities. These results collectively suggest that (a) UV-B exposure preferentially induces peroxidase-related enzymes, whereas O{sub 3} exposure invokes the enzymes of superoxide dismutase/ascorbate-glutathione cycle, and (b) in contrast to O{sub 3}, UV-B exposure generated activated oxygen species by increasing NADPH-oxidase activity. 10 figs., 4 tabs.

Authors:
; ;  [1]
  1. Univ. of Guelph, Ontario (Canada)
Publication Date:
OSTI Identifier:
255241
Resource Type:
Journal Article
Journal Name:
Plant Physiology (Bethesda)
Additional Journal Information:
Journal Volume: 110; Journal Issue: 1; Other Information: PBD: Jan 1996
Country of Publication:
United States
Language:
English
Subject:
56 BIOLOGY AND MEDICINE, APPLIED STUDIES; ARABIDOPSIS; BIOLOGICAL RADIATION EFFECTS; BIOCHEMISTRY; OZONE; BIOLOGICAL EFFECTS; ENZYMES; ACTIVITY LEVELS; ULTRAVIOLET RADIATION

Citation Formats

Rao, M V, Paliyath, G, and Ormrod, D P. Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana. United States: N. p., 1996. Web. doi:10.1104/pp.110.1.125.
Rao, M V, Paliyath, G, & Ormrod, D P. Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana. United States. doi:10.1104/pp.110.1.125.
Rao, M V, Paliyath, G, and Ormrod, D P. Mon . "Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana". United States. doi:10.1104/pp.110.1.125.
@article{osti_255241,
title = {Ultraviolet-B- and ozone-induced biochemical changes in antioxidant enzymes of Arabidopsis thaliana},
author = {Rao, M V and Paliyath, G and Ormrod, D P},
abstractNote = {Earlier studies with Arabidopsis thaliana exposed to ultraviolet B (UV-B) and ozone (O{sub 3}) have indicated the differential responses of superoxide dismutase and glutathione reductase. In this study, we have investigated whether A. thaliana genotype Landsberg erecta and its flavonoid-deficient mutant transparent testa (tt5) is capable of metabolizing UV-B- and O{sub 3}-induced activated oxygen species by invoking similar antioxidant enzymes. UV-B exposure preferentially enhanced guaiacol-peroxidases, ascorbate peroxidase, and peroxidases specific to coniferyl alcohol and modified the substrate affinity of ascorbate peroxidase. O{sub 3} exposure enhanced superoxide dismutase, peroxidases, glutathione reductase, and ascorbate peroxidase to a similar degree and modified the substrate affinity of both glutathione reductase and ascorbate peroxidase. Both UV-B and O{sub 3} exposure enhanced similar Cu,Zn-superoxide dismutase isoforms. New isoforms of peroxidases and ascorbate peroxidase were synthesized in tt5 plants irradiated with UV-B. UV-B radiation, in contrast to O{sub 3}, enhanced the activation oxygen species by increasing membrane-localized NADPH-oxidase activity and decreasing catalase activities. These results collectively suggest that (a) UV-B exposure preferentially induces peroxidase-related enzymes, whereas O{sub 3} exposure invokes the enzymes of superoxide dismutase/ascorbate-glutathione cycle, and (b) in contrast to O{sub 3}, UV-B exposure generated activated oxygen species by increasing NADPH-oxidase activity. 10 figs., 4 tabs.},
doi = {10.1104/pp.110.1.125},
journal = {Plant Physiology (Bethesda)},
number = 1,
volume = 110,
place = {United States},
year = {1996},
month = {1}
}