[Physico-chemical properties of the thrombolytic compound longolytin].

A preparation exhibiting high fibrinolytic activity and ability to activate plasminogen was isolated from cultivation medium of Arthrobotrys longa. Homogeneous protein, obtained after gel filtration on Sephadex G-100, had molecular mass 28,600, pI-3.68-3.74, optimum activity at pH 6.0-9.0 and temperature optimum at 37 degrees. The enzyme proved to be serine proteinase as shown by analysis using inhibitors; it required thiol groups.