Production of Chemotherapeutic Agent L-asparaginase from Gamma-Irradiated Pseudomonas aeruginosa WCHPA075019.

Jordan Journal of Biological Sciences

article

Amany, B. Abd El–Aziz¹  Wesam, A. Hassanein²  Zakaria, A. Mattar¹  Rabab,A. El-Didamony² 

[1] Microbiology Department, National Center for Radiation Research and Technology;Department of Botany and Microbiology، Faculty of Science, Zagazig University

关键词: pseudomonas aeruginosa;    16s rDNA analysis;    L-asparaginase;    Optimization;    Gamma radiation;    Purification;    Enzyme activity;    Anti-cancer.;   

DOI  :  10.54319/jjbs/140304

学科分类：生物科学（综合）

来源: Hashemite University, Deanship of Research and Higher Studies

【 摘 要 】

Because of the dangers and painful effects of chemotherapeutic drugs, the need for therapeutic agents with less adverse effects will increase several times in the coming years. L-asparaginase enzyme is an effective antitumor agent, especially acute lymphoblastic leukemia, with no side effects compared to other chemotherapeutic agents. Microorganisms are emerging as a safer source of L-asparaginase. Therefore, the findings of new L-asparaginase-producing bacterial strains with high yield for therapeutic applications become necessary. From twenty bacterial isolates tested for their L-asparaginase activity, 16S rRNA sequencing for the most potent isolate showed that the selected isolate had 100% identity to pseudomonas aeruginosa strain (accession number: WCHPA075019). In the presence of L-asparagine (1%) and glucose (1%) as nitrogen and carbon sources at a low dose of gamma radiation (0.75 kGy), the maximum productivity of Lasparaginase was reached after 2 days at 35 ° C, pH 7.6 under shaking at 200 rpm. Purification of L-asparaginase with 70% ammonium sulphate, followed by Sephadex G100 increases enzyme purity by 1.5-fold after gel filtration. Pure Lasparaginase had a molecular weight of 123 kDa by SDS- PAGE. The maximum activity of the enzyme against L-asparagine was detected at 35°C and pH 9.0 after 30 min and 200 mM substrate. L-asparaginase activated in the presence of metal ions such as K+, and Na+, not affected when exposed to EDTA and strongly inhibited in the presence of Ba2+, and Cd2+. The anticancer activity of the purified enzyme was tested in vitro against three types of cell line carcinoma. The growth inhibition of L-asparaginase for HEPG2 carcinoma cell line (IC50 value of 3.5 µg/ml) was greater than the inhibition of HCT and MCF-7 carcinoma cell lines with IC50 value of 3.8 and 12.5 µg/ml, respectively relative to the growth of the untreated control cells.

【 授权许可】

CC BY