Purification, N-terminal amino acid sequence, and some properties of Cu, Zn-superoxide dismutase from Japanese flounder (Paralichthys olivaceus) hepato-pancreas

Citation
K. Osatomi et al., Purification, N-terminal amino acid sequence, and some properties of Cu, Zn-superoxide dismutase from Japanese flounder (Paralichthys olivaceus) hepato-pancreas, COMP BIOC B, 128(4), 2001, pp. 751-760
Citations number
35
Categorie Soggetti
Biochemistry & Biophysics
Journal title
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
ISSN journal
10964959 → ACNP
Volume
128
Issue
4
Year of publication
2001
Pages
751 - 760
Database
ISI
SICI code
1096-4959(200104)128:4<751:PNAASA>2.0.ZU;2-J
Abstract
Cu, Zn-superoxide dismutase (SOD) has been purified to homogeneity from Jap anese founder Paralichthys olivaceus hepato-pancreas, The purification of t he enzyme was carried out by an ethanol/chloroform treatment and acetone pr ecipitation, and then followed by column chromatographies on Q-Sepharose, S -Sepharose and Ultrogel AcA 54. On SDS-PAGE, the purified enzyme gave a sin gle protein band with molecular mass of 17.5 kDa under reducing conditions, and showed approximately equal proportions of 17.8 and 36 kDa molecular ma ss under non-reducing conditions. Three bands were obtained when the purifi ed enzyme was subjected to native-PAGE, both on protein and activity staini ng, but the electrophoretic mobility of the purified enzyme differed from t hat of bovine erythrocyte Cu, Zn-SOD. Isoelectric point values of 5.9, 6.0 and 6.2, respectively, were obtained for the three components. The N-termin al amino acid sequence of the purified enzyme was determined for 25 amino a cid residues, and the sequence was compared with other Cu, Zn-SODs. The N-t erminal alanine residue was unacetylated, as in the case of swordfish SOD. Above 60 degreesC, the thermostability of the enzyme was much lower than th at of bovine Cu, Zn-SOD. (C) 2001 Elsevier Science Inc. AII rights reserved .