| 摘要 |
Streptococcal enzymes are prepd. by fermenting at pH 3.5 and eluting the enzymes, esp. Streptolysin O, hyaluronate-lyase, Streptokinase and streptodornase from the killed cocci with 0.1 M phosphate buffer ato pH 8, then (1) precipitating enzymes with (NH4)2SO4 dissolving the pptn. in 0.02 M phosphate buffer and chromatographing on cross-linked DEAE-agarose and recovering the products by gradient elution, or (2) diluting the culture with an equal vol. of 0.1M phosphate added with stirring at pH 6-7, separating the hyaluronate-lyase from the soln. after adsorption by adding (NH4)2SO4, separating the enzyme by centrifugation, dialysing against 0.02, phosphate buffer and recovering pure from DEAE-agarose, or (3) precipitating pure Streptokinase and Streptodornase by adding 10% NaCl, pptated and Ca3(PO4)2, fractionally precipitating with (NH4)2SO, and chromatographing on DEAE-agarose or (4) adsorbing the enzymes e.g. Streptolysin O, Streptokinase and streptodornase on silica gel used for the recovery of hyaluronate-lyase with water at pH 9.5-10.5, preferably 10, and recovering the pure Streptokinase and Streptodornase as in (3) and by chromatography on DEAE-agarose. Economic process without use of large amounts of precipitants e.g. alcohols and (NH4)2SO4 for isolation of many individual enzymes, rather than one specific one, from the fermentation liquor. The enzymes are used in diagnosis of Streptococci in serum, and for clinical treatment. The killed Streptococci act as centres of crystallisation. |
