Purification, Characterization and Comparison between Two New L-asparaginases from Bacillus PG03 and Bacillus PG04
Mahsa Rahimzadeh*, 1, 4, Manijeh Poodat2, Sedigheh Javadpour3, Fatemeh Izadpanah Qeshmi4, Fereshteh Shamsipour5
Identifiers and Pagination:Year: 2016
First Page: 35
Last Page: 45
Publisher Id: TOBIOCJ-10-35
Article History:Received Date: 7/02/2016
Revision Received Date: 25/08/2016
Acceptance Date: 22/09/2016
Electronic publication date: 04/11/2016
Collection year: 2016
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution-Non-Commercial 4.0 International Public License (CC BY-NC 4.0) (https://creativecommons.org/licenses/by-nc/4.0/legalcode), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
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.
L- asparaginases were produced using different culture media and were purified using ion exchange chromatography.
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 km and Vmax 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.
The results revealed that both enzymes had appropriate characteristics and thus could be a potential candidate for medical applications.