Clinical Laboratories Sciences Department, College of Applied Medical Science, Hafr Al Batin University, Hafr Al Batin, 319 91, Saudi Arabia.
Environ Sci Pollut Res Int. 2022 Feb;29(8):11243-11254. doi: 10.1007/s11356-021-16175-5. Epub 2021 Sep 17.
Asparaginases important role in the treatment of leukemia. It is part of chemotherapy in the treatment of leukemia in the last three decades. L-Asparaginase is isolated from Fusarium sp. isolated from soil and purified using ammonium sulfate precipitation and Sephadex G 100. Characterization of the crude enzyme revealed it is a metalloprotease inhibited by EDTA. Hg, Cd, and Pb also inhibited the enzyme. Mg, Zn, and Ca activated L-asparaginase. Furthermore, kinetic studies of purified enzyme were carried out. V and K were 0.031 M and 454 U/mL, respectively. The optimum temperature was 30 °C and the optimum pH was 7. Concerning substrate specificity, gelatin and casein in addition to L-asparagine were tested. The enzyme was found to be nonspecific that could hydrolyze all tested substrates at different rates. The maximum enzyme activity was recorded in the case of L-asparagine, followed by casein and gelatin, respectively. The molecular weight of L-asparaginase was 22.5 kDa. The antileukemic cytotoxicity assay of the enzyme against RAW2674 leukemic cell lines by MTT viability test was estimated. The enzyme exhibited antileukemic activity with IC of 50.1 UmL. The current work presents additional information regarding the purification and characterization of the enzyme produced by Fusarium sp. and its evaluation as a potential antileukemic chemotherapeutic agent.
天冬酰胺酶在白血病治疗中具有重要作用。它是过去三十年中白血病化疗治疗的一部分。L-天冬酰胺酶是从土壤中分离的木霉属真菌中分离出来的，并通过硫酸铵沉淀和 Sephadex G 100 纯化。粗酶的特性研究表明，它是一种金属蛋白酶，被 EDTA 抑制。Hg、Cd 和 Pb 也抑制该酶。Mg、Zn 和 Ca 则激活 L-天冬酰胺酶。此外，还对纯化酶进行了动力学研究。V 和 K 分别为 0.031 M 和 454 U/mL。最适温度为 30°C，最适 pH 值为 7。关于底物特异性，除了 L-天冬酰胺外，还测试了明胶和酪蛋白。结果发现该酶是非特异性的，可以以不同的速率水解所有测试的底物。在 L-天冬酰胺的情况下记录到最大的酶活性，其次是酪蛋白和明胶。L-天冬酰胺酶的分子量为 22.5 kDa。通过 MTT 活力试验测定了酶对 RAW2674 白血病细胞系的抗白血病细胞毒性。该酶表现出抗白血病活性，IC50 为 50.1 UmL。本工作提供了有关木霉属真菌产生的酶的纯化和特性的更多信息，并评估了其作为潜在的抗白血病化疗药物的用途。
