Purification and biochemical characterization of a novel copper, zinc superoxide dismutase from liver of camel (Camelus dromedarius): An antioxidant enzyme with unique properties
Küçük Resim Yok
Tarih
2019
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Academic Press Inc.
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
A novel copper, zinc superoxide dismutase (CuZnSOD) was purified to homogeneity from the liver of an animal well adapted to the stressful living conditions of the desert, the camel (Camelus dromedarius). The biochemical properties of camel liver CuZnSOD were examined. The purified enzyme had a native molecular weight of 28 kDa, as judged by gel filtration chromatography, and showed a single band at 27 kDa on SDS-PAGE, indicating that it is a monomeric protein. Optimal activity of the purified enzyme occurred at 43 °C and pH 6.0, and the activation energy was 1.42 kJ/mol. CuZnSOD activity was strongly inhibited by ?-ME, DTT, H 2 O 2 and SDS and slightly inhibited by EDTA, NaN 3 and PMSF. Al 3+ , Ca 2+ , Cd 2+ , Mg 2+ and Zn 2+ stimulated CuZnSOD activity, whereas Ba 2+ , Co 2+ , Fe 2+ and Ni 2+ inhibited it. The purified enzyme contained 0.010 µg of Cu and 0.69 µg of Zn per mg of protein. K m , V max , k cat and k cat /K m values for NBT and riboflavin were 16.27 and 0.16 µM, 20.85 and 21.54 U/mg, 9.65 and 9.97 s ?1 , and 0.59 and 62.33 s -1 µM ?1 , respectively. Camel liver CuZnSOD exhibited unique biochemical properties compared to those of other CuZnSODs, including lower molecular weight with a monomeric structure, higher optimum temperature, very low E a , very low optimum pH, very low contents of Cu and Zn, and higher affinity, turnover number and catalytic efficiency for riboflavin. These unique properties of camel liver CuZnSOD might be related to the ability of this animal to inhabit stressful desert conditions. © 2019 Elsevier Inc.
Açıklama
Anahtar Kelimeler
Biochemical characterization, Camel, Camelus dromedarius, Copper, zinc superoxide dismutase, Purification, Stressful desert conditions, Unique properties, copper zinc superoxide dismutase, cuprous ion, ferrous ion, magnesium ion, riboflavin, sodium azide, zinc ion, animal tissue, Article, biochemical analysis, catalytic efficiency, controlled study, desert, dromedary, environmental stress, enzyme activity, enzyme purification, gel filtration chromatography, kinetic parameters, liver homogenate, molecular weight, nonhuman, oxidative stress, pH, polyacrylamide gel electrophoresis, priority journal, protein determination, turnover number, zymography, Biochemical characterization, Camel, Camelus dromedarius, Copper, zinc superoxide dismutase, Purification, Stressful desert conditions, Unique properties, copper zinc superoxide dismutase, cuprous ion, ferrous ion, magnesium ion, riboflavin, sodium azide, zinc ion, animal tissue, Article, biochemical analysis, catalytic efficiency, controlled study, desert, dromedary, environmental stress, enzyme activity, enzyme purification, gel filtration chromatography, kinetic parameters, liver homogenate, molecular weight, nonhuman, oxidative stress, pH, polyacrylamide gel electrophoresis, priority journal, protein determination, turnover number, zymography
Kaynak
Bioorganic Chemistry
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
86
