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Published on: November 3, 2018
Purification, Characterization and Comparison between Two New L-asparaginases from Bacillus PG03 and Bacillus PG04
Mahsa Rahimzadeh1, Manijeh Poodat2, Sedigheh Javadpour3
1Molecular Medicine Research Center, Department of Biochemistry, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; Food and Cosmetic Health Research Center, Department of Biochemistry, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
Background:
L-asparaginase has been used as a chemotherapeutic agent in treatment of lymphoblastic leukemia. In the present investigation, Bacillus sp. PG03 and Bacillus sp. PG04 were studied.
Methods:
L- asparaginases were produced using different culture media and were purified using ion exchange chromatography.
Results:
Maximum productivity was obtained when asparagine was used as the nitrogen source at pH 7 and 48 h after cultivation. New intracellular L-asparaginases showed an apparent molecular weight of 25 kDa and 30 kDa by SDS-PAGE respectively. These enzymes were active in a wide pH range (3-9) with maximum activity at pH 6 for Bacillus PG03 and pH 7 for Bacillus PG04 L-asparaginase. Bacillus PG03 enzyme was optimally active at 37 ˚C and Bacillus PG04 maximum activity was observed at 40˚C. Kinetic parameters k and V of both enzymes were studied using L-asparagine as the substrate. Thermal inactivation studies of Bacillus PG03 and Bacillus PG04 L-asparaginase exhibited t1/2 of 69.3 min and 34.6 min in 37 ˚C respectively. Also T50 and ∆G of inactivation were measured for both enzymes.
Conclusion:
The results revealed that both enzymes had appropriate characteristics and thus could be a potential candidate for medical applications.
