Optimization and characterization of antileukemic l-asparaginase produced by Fusarium solani endophyte

Abstract

Abstractl-asparaginase is an antileukemic enzyme that hydrolyzes l-asparagine into l-aspartic acid and ammonia, causing cell starvation and apoptosis in susceptible leukemic cell populations. Currently, l-asparaginase obtained from bacterial sources is constrained by several issues, including lesser productivity, stability, selectivity, and higher toxicity. The goal of this study is to provide fungal l-asparaginase with in-vitro effectiveness towards different human carcinomas. l-asparaginase from endophytic Fusarium solani (Gene Bank accession number MW209717) isolated from the roots of the medicinal plant Hedera helix L. was characterized and optimized experimentally for maximum l-asparaginase production in addition to evaluating its subsequent cytotoxicity towards acute monocytic leukemia and human skin fibroblast cell lines. The enzyme production was maximized using potato dextrose media (15.44 IU/ml/hr) at the 5th and 6th days of fermentation with incubation temperature 30 °C, 3% asparagine, 150–180 rpm agitation rate and a 250 ml flask. Enzyme characterization studies revealed that the enzyme maintained its thermal stability with temperatures up to 60 °C. However, its optimal activity was achieved at 35 °C. On measuring the enzymatic activity at various temperatures and different pH, maximum enzyme activity was recorded at 40 °C and pH 8 using 0.1 M asparagine concentration. Results also revealed promising cytotoxic activity against acute monocytic leukemia with IC50 = 3.66 µg/ml and low cytotoxicity against tested normal human skin fibroblast cell line which suggested that it might have selective toxicity, and consequently it could be used as a less toxic alternative to the current formulations.

Production, characterization, and applications of a novel thermo-acidophilic L-asparaginase of Pseudomonas aeruginosa CSPS4

“…L-asparaginase belongs to one of the important biotechnological groups of therapeutic and industrial enzymes that share 40% of global sales of enzymes (Qeshmi et al 2022). Due to the potential to hydrolyze L-asparagine (an essential amino acid), the enzyme has been successfully employed for destroying leukemia cells (Osama et al 2023). Recent investigations have also reported the role of the enzyme in treating human neoplastic cells (Alrumman et al 2019).…”

“…The enzyme finds several biotechnological applications related to human health in the food and pharmaceutical industries (Batool et al 2016;Brumano et al 2019). L-asparaginases grabbed special attention due to their major role as an antitumor agent (Shrivastava et al 2016;Luo et al 2018;Osama et al 2023). Tumor cells cannot synthesize asparagine due to the lack of an asparagine synthase enzyme, which leads to inhibition of translation followed by complete cell cycle arrest (Povlova et al 2018).…”

“…Tumor cells cannot synthesize asparagine due to the lack of an asparagine synthase enzyme, which leads to inhibition of translation followed by complete cell cycle arrest (Povlova et al 2018). By taking advantage of this fact, asparaginase was employed as an antitumor agent for diminishing the essential L-asparagine for the growth of leukemic cells (Mahajan et al 2014;Ali et al 2016;Osama et al 2023). Several commercial L-asparaginases (Bionase®, Spectrila®, Erwinase®, and Oncaspar®) are available in the market that are chiefly sourced from either Escherichia coli or Erwinia chrysanthemi (Kataria et al 2015;Vimal and Kumar 2022).…”