Ramadevi S, Shelin Ruby, Shanmugaraja Meenakshi
Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam, 603103, Chennai, Tamil Nadu, India.
Department of Biotechnology, Mepco Schlenk Engineering College, Sivakasi, 626005, Tamil Nadu, India.
Curr Microbiol. 2023 Mar 28;80(5):150. doi: 10.1007/s00284-023-03253-9.
Escherichia coli Nissle 1917 (EcN) is one of the probiotics that has drawn more attention from researchers in recent days as it extends many host beneficial effects. EcN is being used as a treatment regimen especially for gastrointestinal disorders for more than 100 years. Apart from its clinical applications in its original form, EcN is being genetically engineered to meet the therapeutic requirements which ultimately led to the gradual transformation of EcN from being a mere food supplement to a complex therapeutic agent. However, comprehensive analysis of physiological characterization of EcN is inadequate. In this study, we have systematically studied various physiological parameters and found that EcN grows very well at the normal as well as at stressful conditions such as temperature (30, 37 and 42 °C), nutritional (minimal and LB), pH (ranging from 3 to 7) and osmotic stress (0.4 M NaCl, 0.4 M KCl, 0.4 M Sucrose and salt conditions). However, EcN shows nearly onefold reduction in viability at extreme acidic conditions (pH 3 and 4). It produces biofilm and curlin very efficiently compared to the laboratory strain MG1655. Through genetic analysis we have also shown that EcN exhibits high level of transformation efficiency and greater ability to retain heterogenous plasmid. Very interestingly, we have found that EcN is highly resistant to P1 phage infection. Since, EcN is being exploited largely for its clinical and therapeutic applications, the results that we have reported here would add more value and further expand its scope in clinical and biotechnological research.
大肠杆菌Nissle 1917（EcN）是近年来受到研究人员更多关注的益生菌之一，因为它具有多种宿主有益作用。100多年来，EcN一直被用作治疗方案，尤其是用于治疗胃肠道疾病。除了其原始形式的临床应用外，EcN正在进行基因工程改造以满足治疗需求，这最终导致EcN从单纯的食品补充剂逐渐转变为复杂的治疗剂。然而，对EcN生理特性的全面分析还不够充分。在本研究中，我们系统地研究了各种生理参数，发现EcN在正常条件以及温度（30、37和42°C）、营养（基本培养基和LB培养基）、pH（3至7）和渗透胁迫（0.4M NaCl、0.4M KCl、0.4M蔗糖和盐条件）等应激条件下生长良好。然而，EcN在极端酸性条件（pH 3和4）下的活力几乎降低了一倍。与实验室菌株MG1655相比，它能非常有效地产生生物膜和卷曲菌素。通过遗传分析我们还表明，EcN表现出高水平的转化效率和更强的保留异源质粒的能力。非常有趣的是，我们发现EcN对P1噬菌体感染具有高度抗性。由于EcN在很大程度上被用于临床和治疗应用，我们在此报告的结果将增加更多价值，并进一步扩大其在临床和生物技术研究中的应用范围。
