[Optimization of the nutrient medium for Actinomyces spheroides--producer of proteolytic enzymes with fibrinolytic activity].

Optimization of the medium for growing Actinomyces spheroides producing proteolytic exoenzymes with the fibrinolytic activity was performed by the method of mathematical planning. The composition of the medium is as follows (%): glucose 7.1, sodium citrate, trisubstituted, 0.48; (NH4)2SO4, 0.15; MgSO4, 0.575; KH2PO4, 0.2; ZnSO4, 0.001; FeSO4, 0.002. The fibrinolytic activity of the cultural broth on this medium is three times as high as on the initial medium (7142 units). Changes in the ratio between components of the medium lead to changes in the ratio between the fibrinolytic and caseinolytic activities. Therefore, Act. spheroides, strain 1, produces exoenzymes which differ by their substrate specificity. The ratio between the fibrinolytic and caseinolytic activities of the complex on the optimized medium is twice as high as on the initial medium.