The Fibrinolytic Activity Of Protease Produced By The Streptomyces C-3662, Cgw-3 Purification, Physicochemical Properties And Pharmacodynamics,

Many Streptomyces strains secrete large amounts of proteases, although Streptomyces are the most famous antibiotic-producing strains. Our study focuses on exploring the possibility of developing, from Streptomyces, a new fibrinolyitics that can degrade effectively thrombus.Streptomyces strain, named Streptomyces sp. C-3662, which secretes significant amounts of proteases with a relatively high specificity to fibrin, was selected out from various Streptomyces isolates in China soil.The appropriate fermentation procedure and medium compositions for Streptomyces sp. C-3662 were developed to obtain fermentation broth with optimal fibrinolytic activity. Briefly, the spores of Streptomyces sp. C-3662 incubated for 5-7 days at 28℃ on synthetic medium No. 5 slant were inoculated into liquid seed medium composed of glucose 2.5%, starch 1.0%, soybean meal 2.0%, KH₂PO₄ 0.05%, MgSO₄·7H₂O 0.05% and CaCO₃ 0.3%, after shaking for 48 hours at 28℃ the seed culture was transferred into the same seed culture medium and shaking for fermentation for 96 hours at 28℃. The fermentation supernatant was collected by vacuum filtration (adding 1% diatomite as filter aid).A novel protease, designated as CGW-3, was isolated from the above supernatant. The purification procedure applied as following. The ammonium sulfate was added to the supernatant to over 90% saturation, standing in cold room (4-8℃) for overnight, collecting precipitate by vacuum filtration ( adding 1% diatomite as filter aid ). The precipitate was dissolved in water and desalted by Sephadex G25. Most pigments of small sizes in the solution were removed in this...