Purification of Two Superoxide Dismutase Isozymes and Their Subcellular Localization in Needles and Roots of Norway Spruce (Picea abies L.) Trees

Abstract

Two isozymes of superoxide dismutase (SOD; EC 1.15.1.1) were purified from Norway spruce (Picea abies L.) needles to apparent electrophoretic homogeneity. Purification factors were 354 for SOD I and 265 for SOD II. The native molecular mass of both purified enzymes was approximately 33 kD, as determined by gel filtration. The subunit molecular weights, as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, were 20,000 for SOD I and 16,000 for SOD II in the presence of 2-mercaptoethanol, and 15,800 and 15,000, respectively, in its absence. These results indicate that the native enzymes were homodimers whose subunits contained intrachain disulfide bonds. Isoelectric points determined by nondenaturing isoelectric focusing were 4.5 and 5.5 for SOD I and 11, respectively. NH2-terminal sequence analysis of the first 22 to 23 amino acids revealed 70 to 75% sequence identity with chloroplastic CuZn SODs from other plant species for SOD I, and 75% sequence identity with the cytosolic CuZn SOD from Scots pine for SOD II. SOD I was the major activity in needles and it was associated with chloroplasts. SOD II activity was dominant in roots.

Antioxidative enzymatic profile of mushrooms stored at low temperature

“…Two bands of each accession were more towards cathodic side, possibly having net positive charge and high molecular weight, while rest bands were towards anode indicating net negative charge and corresponding low molecular weights. The number of isozymes of SOD had been reported to vary, viz., 2 in roots and needles of Picea abies (Kroniger et al 1992), 3 in Spirulina (Lumsden and Hall 1974), kidney bean leaves (Kono et al 1979), Brussels sprouts (Walker et al 1991) and Fagopyrum tataricum cv. Wutai leaves (Wang et al 1993), 4 in maize (Gianopolitis and Ries 1977) and tomato (Kumar et al 2006) and 5 in maize (Baum et al 1983).…”

Antioxidant Metabolism Associated with Summer Leaf Senescence and Turf Quality Decline for Creeping Bentgrass

“…Most of these studies suggested that environmental factors, such as light, temperature, or even airborne photooxidants to be the forces causing seasonal antioxidants fluctuations. Kroniger et al (1992) suggested that the seasonal variation in antioxidants to be developmentally controlled. In our study, antioxidant enzyme activities decreased as air temperature increased, but increased when temperature dropped, indicating that temperature was involved in the changes in the antioxidant system for creeping bentgrass.…”

Physiological responses to gradual drought stress in the diploid hybrid Pinus densata and its two parental species

“…Superoxide dismutase activity was determined by the inhibition of the formation of epinephrine at pH 10.4 and 30°C (Kroniger et al 1992). One unit of superoxide dismutase activity was defined as the amount of enzyme that inhibited the epinephrine formation by 50%.…”