The aim of the master's thesis was to optimize the production medium for obtaining recombinant proteinase pernisine using Streptomyces rimosus. The optimization of the medium was started with the GOTC medium, which has been optimized previously for the production of oxytetracycline antibiotics. We have studied how different sources of carbon and nitrogen in the production medium affect the production of perinsine. We found that the concentration of soy flour as a source of nitrogen greatly influences the production of pernisine. Concentration of starch does not have a significant effect on the production of pernisine, however, at lower concentrations of starch in the medium, higher pernisine activity was measured. In the first part of the experiment, two different S. rimosus production strains were used (PER4 and PER) and compared with the control strain KON (wild type not producing pernisine). Given the results of the first experiment, only the PER5 production strain was used hereafter, since higher pernisine activity was measured in this strain. In the second part of the master's thesis, however, we found that we achieved the highest pernsine activity after 5 days of cultivation. We also found that the ratio between carbon and nitrogen is very important. We evaluated the effect of various media components, such as simple sugars, inorganic and organic sources of nitrogen and oils. The most positive effect on the pernisine production was influenced by fish and soy oil at lower concentrations (up to 10 g/L). High pernisine activity was also measured in media with other sources of nitrogen, such as: urea, ammonium sulphate, soy protein flour and yeast hydrolyzate. Of the tested carbon sources, only mannitol and dextrin had a positive effect.
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