Characterization and Evaluation of the Anti-proliferative Activity and Hypersensitivity  of L-Asparaginase from Trichosporon asahii Isolate ChL11 and Candida palmioleophila  Isolate JK12

Tekeba  Sisay; Naomi  Maina; Victor  Mobegi; Sabina  Wachira

doi:10.18502/ajmb.v17i3.19275

Tekeba Sisay Department of Molecular Biology and Biotechnology, Pan African University Institute for Basic Sciences, Technology and Innovations (PAUSTI), Nairobi, Kenya
Naomi Maina Department of Molecular Biology and Biotechnology, Pan African University Institute for Basic Sciences, Technology and Innovations (PAUSTI), Nairobi, Kenya
Victor Mobegi Department of Biochemistry, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya
Sabina Wachira Kenya Medical Research Institute, Center for Traditional Medicine and Drug Research, Nairobi, Kenya

DOI: https://doi.org/10.18502/ajmb.v17i3.19275

Keywords: Ammonium sulfate, Asparaginase, Asparagine, Dickeya chrysanthemi, Glutaminase, Se-phadex, Trichosporon asahii

Abstract

Background: L-Asparaginase is a crucial enzyme to treat Acute Lymphoblastic Leukemia (ALL), as it depletes L-asparagine, an essential amino acid for cancer cell survival. However, its clinical use is often restricted due to hypersensitivity reactions. This study examined the anti-proliferative effects and hypersensitivity of fungal L-aspara-ginases (L-ASNases) from Trichosporon asahii isolate ChL11 (TaIChL11 L-ASNase) and Candida palmioleophila isolate JK12 (CpIJK12 L-ASNase).

Methods: The enzymes were produced and purified through ammonium sulfate precipitation, dialysis, and Sephadex G-100 chromatography, and tested on leukemia cells and BALB/c female mice to assess immune responses.

Results: TaIChL11 L-ASNase had a molecular weight of 40 kDa, Michaelis constant (K_M) of 1.66×10⁻² mM, and V_max of 37.23 mM/min, while CpIJK12 L-ASNase had a molecular weight of 135 kDa, K_M of 2.3×10⁻² mM, and V_max of 14.03 mM/min. Both enzymes exhibited significant anti-proliferative effects against CCRF-CEM cancer cells, with half-maximal inhibitory concentration (IC₅₀) values of 2.74 U/ml for TaIChL11 L-ASNase and 3.30 U/ml for CpIJK12 L-ASNase after 48 hr, improving further after 72 hr. They also showed low cytotoxicity toward normal Vero E6 cells. in vivo studies demonstrated that TaIChL11 ASNase-treated mice had significantly lower Immunoglobulin (Ig) G levels than those treated with commercial L-ASNase from Erwinia chrysanthemi (Owenism) (p<0.005), with no detectable IgE response.

Conclusion: These findings indicate that fungal L-ASNases, particularly TaIChL11 ASNase, with lower L-glutaminase activity and a favorable safety profile, could be promising alternatives to bacterial L-ASNases, potentially enhancing ALL treatment with fewer side effects.