Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India.
Department of Genetic Engineering, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India.
Sci Rep. 2018 Dec 20;8(1):18013. doi: 10.1038/s41598-018-36161-1.
L-asparaginase, a therapeutic involved in cancer therapy, from Bacillus tequilensis PV9W (ansA gene) was cloned and over expressed in Escherichia coli BL21 (DE3), achieved the aim of maximizing the yield of the recombinant enzyme (6.02 ± 1.77 IU/mL) within 12 h. The native L-asparaginase of B. tequilensis PV9W was encapsulated using solid lipid particles by hot lipid emulsion method, which is reported for first time in this study. Subsequently, the lipid encapsulated L-asparaginase (LPE) was characterized by SEM, UV-Vis spectroscopy, FT-IR, SDS-PAGE and its thermo stability was also analyzed by TGA. Further characterization of LPE revealed that enzyme was highly stable for 25 days when stored at 25 °C, showed high pH (9) tolerance and longer trypsin half-life (120 min). In addition, the cytotoxic ability of LPE on HeLa cells was highly enhanced compared to the native L-asparaginase from Bacillus tequilensis PV9W. Moreover, better kinetic velocity and lower K values of LPE aided to detect L-asparagine in cell extracts by Differential Pulse Voltammetry (DPV) method. The LPE preparation also showed least immunogenic reaction when tested on normal macrophage cell lines. This LPE preparation might thus pave way for efficient drug delivery and enhancing the stability of L-asparaginase for its therapeutic applications.
来自巴氏毕赤酵母 PV9W 的天冬酰胺酶(ansA 基因)被克隆并在大肠杆菌 BL21(DE3)中过表达,在 12 小时内实现了最大限度提高重组酶产量(6.02±1.77IU/mL)的目标。这是首次在本研究中报道采用热熔脂质乳液法将巴氏毕赤酵母 PV9W 的天然天冬酰胺酶包封于固体脂质颗粒中。随后,通过 SEM、UV-Vis 光谱、FT-IR、SDS-PAGE 对包封的天冬酰胺酶(LPE)进行了表征,并通过 TGA 分析了其热稳定性。进一步的 LPE 特性研究表明,当在 25°C 下储存时,酶在 25 天内高度稳定,具有较高的 pH(9)耐受性和较长的胰蛋白酶半衰期(120 分钟)。此外,与来自巴氏毕赤酵母 PV9W 的天然天冬酰胺酶相比,LPE 对 HeLa 细胞的细胞毒性能力显著增强。此外,LPE 的较低 K 值和更好的动力学速度有助于通过差分脉冲伏安法(DPV)方法检测细胞提取物中的天冬酰胺。在正常巨噬细胞系上进行测试时,LPE 制剂的免疫原性反应最小。因此,这种 LPE 制剂可能为高效药物输送和提高天冬酰胺酶的稳定性以用于治疗应用铺平道路。