title: Purification of streptodornase from Streptococcus equisimilis and its DNA-induced conformational change.
abstract: Extracellular streptodornase was purified from fermentation media of Streptococcus equisimilis by stepwise carboxymethyl-Sepharose column chromatography. The active enzyme fraction was eluted with phosphate buffer containing 0.2 M NaCl. The purified enzyme showed a homogeneity on SDS-PAGE and had a subunit molecular weight of 35 kDa. Conformational change of streptodornase by binding to calf thymus DNA was examined by circular dichroism (CD). CD study clearly showed a DNA-induced conformational change in the secondary structure of streptodornase, resulting in a decrease of alpha-helical content of the enzyme.
authors.affiliation: Department of Food Science and Technology, College of Agriculture, Chungnam National University, Taejon, Korea.
authors.forename: M
authors.initials: M
authors.lastname: Lee
authors.forename: K B
authors.initials: KB
authors.lastname: Song
mesh_terms: D000818:Animals; D002417:Cattle; D002852:Chromatography, Ion Exchange; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D003850:Deoxyribonuclease I / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D046911:Macromolecular Substances; D008970:Molecular Weight; D011485:Protein Binding; D011487:Protein Conformation; D013291:Streptococcus / Q000201:enzymology*
chemical_list: D046911:Macromolecular Substances; D004247:DNA; D003850:Deoxyribonuclease I