title: Purification, Characterization and Comparison between Two New L-asparaginases fromBacillusPG03 andBacillusPG04.
abstract: BACKGROUND
  L-asparaginase has been used as a chemotherapeutic agent in treatment of lymphoblastic leukemia. In the present investigation,Bacillussp. PG03 andBacillussp. 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 forBacillusPG03 and pH 7 forBacillusPG04 L-asparaginase.BacillusPG03 enzyme was optimally active at 37 ˚C andBacillusPG04 maximum activity was observed at 40˚C. Kinetic parameterskmandVmaxof both enzymes were studied using L-asparagine as the substrate. Thermal inactivation studies ofBacillusPG03 andBacillusPG04 L-asparaginase exhibited t1/2of 69.3 min and 34.6 min in 37 ˚C respectively. Also T50and ∆G of inactivation were measured for both enzymes.
  
  
  CONCLUSIONS
  The results revealed that both enzymes had appropriate characteristics and thus could be a potential candidate for medical applications.
authors.affiliation: Molecular 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.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Rahimzadeh
authors.affiliation: Department of Biochemistry, Faculty of Sciences, Payame Noor University of Mashhad, Mashhad, Iran.
authors.forename: Manijeh
authors.initials: M
authors.lastname: Poodat
authors.affiliation: Molecular Medicine Research Center, Department of Microbiology, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
authors.forename: Sedigheh
authors.initials: S
authors.lastname: Javadpour
authors.affiliation: Food and Cosmetic Health Research Center, Department of Biochemistry, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
authors.forename: Fatemeh Izadpanah
authors.initials: FI
authors.lastname: Qeshmi
authors.affiliation: Monoclonal Antibody Research Center, Avicenna Research Institute, (ACECR), Tehran, Iran.
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Shamsipour
keywords: Bacillus PG03; Bacillus PG04; L-asparaginase; Purification; Thermostability