Increased levels of peroxisomal active oxygen-related enzymes in copper-tolerant pea plants

Journal Article · Thu Oct 01 00:00:00 EDT 1987 · Plant Physiol.; (United States)

DOI:https://doi.org/10.1104/pp.85.2.570· OSTI ID:5504238

Palma, J M; Gomez, M; Yanez, J; Del Rio, L A

The effect in vivo of high nutrient levels of copper (240 micromolar) on the activity of different metalloenzymes containing Cu, Mn, Fe, and Zn, distributed in chloroplasts, peroxisomes, and mitochondria, was studied in leaves of two varieties of Pisum sativum L. plants with different sensitivity to copper. The metalloenzymes studied were: cytochrome c oxidase, Mn-superoxide dismutase (Mn-SOD) and Cu,Zn-superoxide dismutase I (Cu,Zn-SOD I), for mitochondria; catalase and Mn-SOD, for peroxisomes; and isozyme Cu,Zn-SOD II for chloroplasts. The activity of mitochondrial SOD isozymes (Mn-SOD and Cu,Zn-SOD I) was very similar in Cu-tolerant and Cu-sensitive plants, whereas cytochrome c oxidase was lower in Cu-sensitive plants. Chloroplastid Cu,Zn-SOD activity was the same in the two plant varieties. In contrast, the peroxisomal Mn-SOD activity was considerably higher in Cu-tolerant than in Cu-sensitive plants, and the activity of catalase was also increased in peroxisomes of Cu-tolerant plants. The higher activities of these peroxisomal active oxygen-related enzymes in Cu-tolerant plants suggest the involvement of reactive oxygen intermediates (O/sub 2//sup -/, OH) in the mechanism of Cu lethality, and also imply a function for peroxisomal Mn-SOD in the molecular mechanisms of plant tolerance to Cu in Pisum sativum L.

• Research Organization: Consejo Superior de Investigaciones Cientificas, Granada, Spain
• OSTI ID: 5504238
• Journal Information: Plant Physiol.; (United States), Vol. 85:2
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CATALASE
ENZYME ACTIVITY
COPPER
TOXICITY
OXIDOREDUCTASES
PISUM
SENSITIVITY
SUPEROXIDE DISMUTASE
CHLOROPLASTS
GENETIC VARIABILITY
LEAVES
MITOCHONDRIA
BACTERIA
BIOLOGICAL VARIABILITY
CELL CONSTITUENTS
ELEMENTS
ENZYMES
LEGUMINOSAE
METALS
MICROORGANISMS
ORGANOIDS
PEROXIDASES
PLANTS
RHIZOBIUM
TRANSITION ELEMENTS
560300* - Chemicals Metabolism & Toxicology