Isolation, Purification and Characterization of an Extracellular Protease from a Locally Isolated Bacillus sphaericus SI-1

Authors

  • Abu Hashem, Sabina Yesmin, Md. Kamruzzaman Pramanik, Md. Saidul Islam, Khandaker Abdur Rahim, Md. Salimullah and Mustafizur Rahman* Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka-1000, Bangladesh

Keywords:

protease, protein, Bacillus sphaericus, phenyl methyl sulfonyl fluoride (PMSF)

Abstract

An extracellular protease was purified from the culture supernatant of Bacillus Sphaericus strain SI1 isolated from local soil sample. The enzyme purification was primarily performed by ammonium sulfate fractionation, centrifugation and dialysis followed by centricon filtration. In each step of processing, enzyme activity was assayed by azocasein digestion method. Partially purified enzyme was further purified by sephadex G-75 column chromatography. Fraction having protease activity was visualized on SDS-PAGE. The molecular weight of the protease was 41.70 KDa, while optimum pH and temperature were 8.4 and 380C respectively. The isolated protease is positively modulated by Ca++ and Mg++ ions but significantly inhibited by EDTA, Cu++, Fe++ and Zn++ ions. The protease enzyme was slowly activated by sodium azide and inhibited by DTT and 2marcaptoethanol. The enzyme activity could be completely eliminated by phenyl methyl sulfonyl fluoride (PMSF). Therefore, all the characteristics suggest the isolated protease to be a serine protease.

Citation
This paper has been cited by the following papers:
1. Characterisation of purified protease from Bacillus subtilis BS166
2. Characterization of partially purified alkaline protease secreted by halophilic bacterium Citricoccus sp. isolated from agricultural soil of northern India

How to Cite

Abu Hashem, Sabina Yesmin, Md. Kamruzzaman Pramanik, Md. Saidul Islam, Khandaker Abdur Rahim, Md. Salimullah and Mustafizur Rahman* (1) “Isolation, Purification and Characterization of an Extracellular Protease from a Locally Isolated Bacillus sphaericus SI-1”, Bioresearch Communications-(BRC). Dhaka, Bangladesh, 1(2), pp. 87-92. Available at: http://bioresearchcommunications.com/index.php/brc/article/view/51 (Accessed: 29November2020).

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