9BAD

Crystal structure of Bacillus subtilis 168 L-asparaginase II with antileukemic activity

9BAD の概要

• エントリーDOI: 10.2210/pdb9bad/pdb
• 分子名称: L-asparaginase 2, SODIUM ION, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: enzyme, leukemia, recombinant, antitumor protein
• 由来する生物種: Bacillus subtilis subsp. subtilis str. 168
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 160000.62

構造登録者

Gomes, J.G.S.,Rocha, B.A.M.,Brandao, L.C.,Furtado, G.P.,Pontes, L.Q.,Lourenzoni, M.R. (登録日: 2024-04-03, 公開日: 2025-10-08, 最終更新日: 2025-11-26)

主引用文献

Brandao, L.C.,da Silva Gomes, J.G.,Pinheiro, D.P.,Caetano, L.F.,Bezerra, M.R.L.,Pontes, L.Q.,Pinheiro, M.P.,de Aquino, A.V.F.G.,Silva, J.M.F.,Souza, P.F.N.,Furtado, C.L.M.,Pessoa, C.,Lourenzoni, M.R.,da Rocha, B.A.M.,Furtado, G.P.
Structural and biochemical characterization of a thermostable Bacillus subtilis L-asparaginase with antiproliferative effects on hematological cancer cell lines.
Int.J.Biol.Macromol., 333:148804-148804, 2025

PubMed Abstract: L-asparaginase catalyzes the hydrolysis of L-asparagine into aspartic acid and ammonia and is found in animals, plants, and microorganisms. Microbial sources are preferred for large-scale production due to their efficiency and ease of cultivation. In this study, we produced and characterized a recombinant L-asparaginase from Bacillus subtilis (Asp-Z). Asp-Z was heterologously expressed in Escherichia coli and purified by affinity chromatography, yielding soluble protein with optimal activity at 55 °C and pH 7.5. The kinetic parameters under these conditions were a Km of 0.47 mM and a Vmax of 52.13 U/mg. Asp-Z was specific for L-asparagine, showing no detectable glutaminase activity, and exhibited antiproliferative effects against hematological cancer cell lines, particularly RAJI and JURKAT, with IC₅₀ values in the micromolar range. In silico analysis revealed distinct immunogenic epitopes between Asp-Z and the commercial E. coli L-asparaginase, suggesting divergent antigenic profiles, whereas crystallographic data revealed a conserved tetrameric fold with a highly flexible active-site loop. Together, these findings highlight Asp-Z as a thermostable, glutaminase-free, and poorly immunogenic enzyme that represents a promising scaffold for optimization through protein engineering toward therapeutic and biotechnological applications.

PubMed: 41203148
DOI: 10.1016/j.ijbiomac.2025.148804

実験手法

X-RAY DIFFRACTION (1.3 Å)