?
Screening of proteases produced by Aspergillus micromycetes active against proteins of the hemostasis system
In this study, the abilities of 15 novel Aspergillus species to produce proteases were screened, including activity against components of human hemostasis. The assessed activities included direct thrombin-, plasmin-, factor Xa-, urokinase-, and protein C-like-activities, as well as activating activities towards the aforementioned proteins with human blood plasma. This was determined using chromogenic peptide substrates in culture fluid samples obtained after submerged fermentation of native strains. Fibrinolytic and plasminogen-activating activities on fibrin plates were also determined. It was found that A. aureolatus and A. tennesseensis are active proteolytics exhibiting plasmin-like activities (116.17 and 87.09 U×10-3, respectively), factor Xa-like activity (76.27 and 77.92 U×10-3, respectively) and urokinase activity (85.99 and 59.91 U×10-3, respectively). The thrombin-like activity was found for A. tabacinus (50.37 U×10-3), and protein C-like activity was noticeable for A. creber, A. jensenii, A. protuberus, and A. ruber (62.90, 65.51, 73.37, and 111.85 U×10-3, respectively). Additionally, more than half of species had the ability to directly activate plasminogen or operate as fibrinolytics. New proteolytic strains were discovered, offering hope for the therapy of cardiovascular disorders. The high specificity and activity of fungal enzymes make them useful in a variety of fields, including medicine and diagnostics.