Department of Biology, College of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
Prince Sultan Bin Abdulaziz Center for Environmental and Tourism Research and Studies, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
Molecules. 2021 Mar 31;26(7):1963. doi: 10.3390/molecules26071963.
L-glutaminase is an important anticancer agent that is used extensively worldwide by depriving cancer cells of L-glutamine. The marine bacterium, was isolated from the Red Sea and selected as the more active L-glutaminase-producing bacteria. L-glutaminase fermentation was optimized at 36 h, pH 8.0, 37 °C, and 3.0% NaCl, using glucose at 1.5% and soybean meal at 2%. The purified enzyme showed a specific activity of 36.08 U/mg, and the molecular weight was found to be 57 kDa by the SDS-PAGE analysis. The enzyme was highly active at pH 8.0 and 37 °C. The kinetics' parameters of and were 12.2 × 10 M and 121.95 μmol/mL/min, respectively, which reflects a higher affinity for its substrate. The anticancer efficiency of the enzyme showed significant toxic activity toward colorectal adenocarcinoma cells; LS 174 T (IC50 7.0 μg/mL) and HCT 116 (IC50 13.2 μg/mL). A higher incidence of cell death was observed with early apoptosis in HCT 116 than in LS 174 T, whereas late apoptosis was observed in LS 174 T more than in HCT 116. Also, the L-glutaminase induction nuclear fragmentation in HCT 116 was more than that in the LS 174T cells. This is the first report on as an L-glutaminase producer that is used as an anti-colorectal cancer agent.
L-谷氨酰胺酶是一种重要的抗癌药物，通过剥夺癌细胞中的 L-谷氨酰胺，在全球范围内得到广泛应用。从红海分离出的海洋细菌被选为更具活性的 L-谷氨酰胺酶产生菌。在 36 小时、pH8.0、37°C 和 3.0%NaCl 的条件下，用 1.5%葡萄糖和 2%豆粕优化 L-谷氨酰胺酶发酵。纯化后的酶比活为 36.08 U/mg，SDS-PAGE 分析发现其分子量为 57 kDa。该酶在 pH8.0 和 37°C 时具有很高的活性。和 的动力学参数分别为 12.2×10 M 和 121.95 μmol/mL/min，反映出对其底物的亲和力更高。该酶对结直肠腺癌细胞（LS 174 T，IC50 为 7.0μg/mL；HCT 116，IC50 为 13.2μg/mL）表现出显著的抗癌效率。与 LS 174 T 相比，HCT 116 中观察到更高的细胞死亡率和早期凋亡，而晚期凋亡则在 LS 174 T 中观察到。此外，与 LS 174 T 细胞相比，HCT 116 细胞中的 L-谷氨酰胺酶诱导核碎片更多。这是首次报道将作为一种用于抗结直肠癌的 L-谷氨酰胺酶产生菌。
