Great improvements have been made in acute lymphoblastic leukemia (ALL) treatment in the past decades, especially due to the use of l-asparaginase (l-ASP). Despite the significant success rate, several side effects mainly caused by toxicity, asparaginase silent inactivation, and cellular resistance, encourage an open debate regarding the optimal dosage and formulation of l-ASP. Alternative sour...

Salmonellae are pathogenic bacteria that induce immunosuppression by mechanisms that remain largely unknown. Previously, we showed that a putative type II l-asparaginase produced by Salmonella Typhimurium inhibits T cell responses and mediates virulence in a murine model of infection. Here, we report that this putative L-asparaginase exhibits L-asparagine hydrolase activity required for Salmone...

Asparaginase is an enzyme that catalyses the hydrolysis of the amino acid L-asparagine to Laspartic acid and ammonia. The asparaginase enzyme described in the DSM’s dossier is intended for use as a processing aid to reduce in food the levels of free L-asparagine, which is a major precursor in the formation of the food contaminant acrylamide. Acrylamide is formed from Lasparagine and reducing su...

Corresponding Author: Mahsa Rahimzadeh Molecular Medicine Research Center, Department of Biochemistry, Faculty of Medicine, Hormozgan University of Medical Sciences, Emam Hossein Boulevard, Bandar Abbas, Iran P.O. Box: 7919693116 Tel; +98-761-6688024 Fax: +98-761-6668478 Email: [email protected] [email protected] Abstract: Bacterial L-asparaginases are amidohydrolases that act on...

In the present study, Streptomyces gulbargensis and its mutant form, S.gulbargensis mu24, immobilized on polyurethane foam were investigated for the production of L-asparaginase using groundnut cake extract as medium. The medium with an initial pH of 8.5 was inoculated with free and immobilized cells separately and then subjected to fermentation by incubation at 40oC and shaking at 200 rev/min....

Gamma irradiation is used on Penicillium cyclopium in order to obtain mutant cells of high L-asparaginase productivity. Using gamma irradiation dose of 4 KGy, P. cyclopium cells yielded L-asparaginase with extracellular enzyme activity of 210.8 ± 3 U/ml, and specific activity of 752.5 ± 1.5 U/mg protein, which are 1.75 and 1.53 times, respectively, the activity of the wild strain. The enzyme wa...

An attempt is made in the present study to optimize the cultural conditions for the production of L-asparaginase by Fusarium oxysporum using submerged fermentation. Different fungal species were isolated and identified using standard manuals, screened initially for the production of extracellular L-asparaginase during their growth on Czapek’s Dox medium containing Lasparagine as sole source of ...

Polyethylene glycol (PEG) conjugation technology has been successfully applied to improve the performance of protein drugs. In this study, L-asparaginase was N-terminal site-specifically modified by alkylating PEG with monomethoxy polyethylene glycol-propionaldehyde (mPEG-ALD20000). The optimum reaction parameters were determined as pH 5.0, a molar ratio of mPEG-ALD2000 to L-asparaginase of 10:...

Different parts of plant species belonging to Solanaceae and Fabaceae families were screened for L-asparaginase enzyme (E.C.3.5.1.1.). Among 34 plant species screened for L-asparaginase enzyme, Withania somnifera L. was identified as a potential source of the enzyme on the basis of high specific activity of the enzyme. The enzyme was purified and characterized from W. somnifera, a popular medic...

A novel fungal gene encoding the Rhizomucor miehei l-asparaginase (RmAsnase) was cloned and expressed in Escherichia coli. Its deduced amino acid sequence shared only 57% identity with the amino acid sequences of other reported l-asparaginases. The purified l-asparaginase homodimer had a molecular mass of 133.7 kDa, a high specific activity of 1,985 U/mg, and very low glutaminase activity. RmAs...