Isoenzyme pattern of superoxide dismutase in different varieties of citrus plants

Abstract

1989. Isoenzyme pattern of superoxide dismutase in different varieties of citrus plants. -Phvsiol Plant. 76: 563-568. Superoxide dismutases (SOD; EC 1.15.L]) in leaves from different cultivars of citrus plants were characterized using isoelectric focusing in polyacrylamide gels. The plants studied included Citrus limonum R, (cvs Verna, Fino, and Eureka), C. paradisi Mac (cvs Red Blush and Marsh), C. auratitium L. (cv. Comun), C. sinensis L. Osbeck (cvs Navel, Valencia, and Salustiano), and C. reticulata B. (cv. Satsuma).The three molecular forms of SOD were distinguished from each other by their different sensitivity to cyanide and H2O2. In C. limonum leaves, four Cu,Zn-SODs, three Fe-SODs and two Mn-SODs were present. However, in leaves from different varieties of C sinensis, C. paradisi, C. aurantium and C. reticulata the activity and number of Fe-SOD isoenzymes were lower than in lemon leaves, whereas the number of MN-SOD isozymes was increased. Cu,Zn-SODs did not show significant variations in the different species and cultivars. The identification of Fe-SODs in several species of the plant family Rutaeeae extends the small number of higher plants where the presence of these Fe-containing metalloenzymes has been demonstrated. Results obtained may be useful from an evolutionary viewpoint and also in mineral nutrition studies using SOD isozymes as markers of functional metals.

Differences in the Activity of Superoxide Dismutase, Polyphenol Oxidase and Cu-Zn Content in the Fruits of Gordal and Manzanilla Olive Varieties

“…The method of Almansa et al (1989) was used for the enzyme extraction: 10.00 g of triturated fruit and 40 ml of extracting buffer 50 mm Tris (tris[hydroxymethyl]aminomethane)-HCl at pH 7.5, containing 0.1 mm EDTA, 5 mm cysteine, and Triton X-100 (0.2% v/v), were homogenized using an Ultra-Turrax model T-25 polytron homogenizer (Janke Kunkel, IKA-Laboratechnik, Germany), keeping the container in an ice bath. The homogenate was filtered through four layers of gauze and centrifuged in a refrigerated centrifuge BeckmanCoulter Avanty J-25 (Beckman Instruments Españ a, S. A., Spain) at 8,000 ¥ g for 15 min at 10 ∞C; the supernatant was collected avoiding the oil droplets.…”

“…The reaction mixture comprised 0.5 ml of enzyme extract and 2.5 ml of substrate formed by 0.1 m citrate buffer at pH 5.0, containing 8 mm 4-methylcatechol (Sciancalepore and Longone, 1984). The increase in absorbance at 410 nm was measured from 20 to 55 seconds and the reaction blank was taken measuring the increase in absorbance provoked by the denatured enzyme extract.…”

“…The method described by Sciancalepore and Longone (1984) for olives was used. A protein precipitate (acetone powder) of the fruit was prepared from 50 g of triturated destoned fruit extracted once with 100 ml of acetone containing 2.5 g of polyethylene glycol at Ð30 ∞C.…”

Response of antioxidant systems and leaf water relations to NaCl stress in pea plants

“…The SOD isozymes were localized on the gels by the photochemical method of Weissiger & Fridovich (1973). Assignment of CuZn-SODs-, Fe-and Mnisoforms was performed by selective inhibition with KCN or H # O # (Salin & Bridges, 1982 ;Almansa et al, 1989). Isozyme activity was quantified by recording the transmittance of gels in a Shimadzu CS-9000 densitometer.…”

Characterization of iron superoxide dismutase cDNAs from plants obtained by genetic complementation in Escherichia coli.

“…However, its presence in a few phylogenetically diverse plant families (13)(14)(15)(16) (14,17). To date, no molecular data have been forthcoming and, because of the lack of a specific probe, it has never been possible to screen plant species for the presence of an FeSOD gene or its transcript.…”