Popis: |
A promising producer of extracellular amylases, Aspergillus flavipes, was selected from 245 strains of marine fungi. Depending on the conditions of growth, this strain produced diverse amylolytic complexes. When grown on a medium containing peptone and yeast extract (pH 7.0), A. flavipes synthesized three forms of amylase, differing in pH optimum (5.5, 6.0, and 7.5). A single form of the enzyme was synthesized either in the absence of peptone from the medium or at the initial pH value of the medium, equal to 8.6. The activity of the isolated amylase forms decreased in the presence of proteolytic enzymes. New, highly stable forms of amylase (with pH optima of 5.5 and 7.5 and maximum activity at 60–80°C) were synthesized in the presence of diisopropyl fluorophosphate, an inhibitor of proteases. |