In the present study thirty actinomycetes isolates collected from Tala drain, Menoufiya Governorate, Egypt. Out of which 12 isolates were protease producer. Isolate no. 2 was selected as the best enzyme producer, identified as Streptomyces phaeochromogenes and was used for further studies. Attempts were made to optimize the cultural condition for getting high yields of enzyme. The optimum level of pH for enzyme production was 7.0 on glycerol-asparagine medium after 8 days. Among carbon sources, starch (1%) supported maximum production of protease followed by glucose, lactose, sucrose, and glycerol. L-asparagine was the best nitrogen source for enzyme production. The purified fraction detected by the appearance of a single band corresponding to 40 kDa in SDS-PAGE, and the enzyme was purified 62.4 fold with overall yield of 19.1 % and specific activity of 78 U/mg. The pure enzyme was stable at all degrees of temperatures (2070ºC). The maximum activity was at pH of 9.0. Casein was the best substrate. KCl, MnCl2 and CaCl2 were the best activators. EDTA did not show any detrimental effect on the enzyme activity. There is a continuous decreasing in the activity due to the increase of SDS and H2O2 concentrations. Enzyme was stable in presence of butanol, toluene and n-hexane The results showed that the purified enzyme had the ability to digest some of natural protein such as coagulated blood, coagulated egg and hair of animal. Also its ability to remove hairs from skins of goat and cow was observed.
Key words: Protease, actinomycetes, microorganisms, purification, industrial proteases uses
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