RESUMO
BACKGROUND AND OBJECTIVES: Fibrinolytic drugs are commonly used for fibrin clot lysis but due to their inappropriate side effects, as well as their high costs, using fibrinolytic enzymes has been paid attention. Bacterial sources of this enzyme are a good alternative for this purpose. The aim was fibrinolysin production through screening of fibrinolysin producing bacteria from environmental samples. MATERIALS AND METHODS: Bacterial isolation was performed from different environmental samples and was screened based on sheep blood clot digestion and culture on plasma plate. The most potent isolate was optimized for different growth parameters including temperature, pH and fibrinolysin production at optimum growth conditions. The stability of produced enzyme at various temperatures and pH and treatment with MgSO4, NiSO4, SDS and EDTA was then investigated. Finally this isolate was identified based on the 16S rRNA sequencing. RESULTS: As a result, from 79 different isolates, the most potent fibrinolysin producer was identified as Alcaligenes faecalis strain 26. This isolate produced 12 mm halo zone on plasma plate. Its optimum growth temperature and pH was 43°C and 7, respectively. The produced enzyme had the best stability at pH 7 and was also active up to 60°C. The fibrinolytic activity of this isolate was reduced following treatment with MgSO4, NiSO4 and also with protease inhibitors, such as SDS and EDTA. CONCLUSION: Based on the obtained results it can be suggested that Alcaligenes faecalis strain 26 has appropriate efficiency for fibrinolysin production that can be used in food industry and medicine.
