缺钾培养诱导结核菌进入休眠状态

Potassium-deficient culture induces Mycobacterium tuberculosis into a dormant state

目的·利用缺钾培养诱导结核菌进入休眠状态。方法·采用缺钾Sauton培养基培养对数生长期结核菌,诱导其进入休眠状态采用菌落计数、刃天青试验和最大或然数法(MPN)检测结核菌存活率及休眠菌比例;采用透射电子显微镜观察结核菌细胞壁增厚情况;用金胺O-尼罗红双荧光染色法检测结核菌脂质聚集及失去抗酸性的情况;药敏实验检测结核菌对异烟肼和利福平的耐药情况。结果·缺钾培养30d后,结核菌发生呈球形、细胞壁增厚、脂质聚集、失去抗酸性及对抗结核药物耐药等改变。结论·缺钾培养可诱导对数期结核菌进入休眠状态。

Objective · To induce Mycobacterium tuberculosis into a dormant state by potassium-deficient culture. Methods · The potassium-deficient Sauton medium was used to culture Mycobacterium tuberculosis at logarithmic phase and to induce it into a dormant state. Colony count, resazurin colorimetric assay, and most probable number （MPN） method were used to measure the survival rate and the proportion of dormant Mycobacterium tuberculosis. Transmission electron microscope （TEM） was used to observe the thickening of cell wall. Auramine O-Nile red double fluorescent staining was employed to detect the lipid accumulation and loss of acid fastness. Drug sensitivity test was performed to detect the drug resistance to isoniazide and rifampicin. Results · Mycobacterium tuberculosis turned to spherical, cell wall thickening, experienced lipid accumulation, and loss of acid fastness, and became resistant to antituberculosis drugs after being cultured under potassium-deficient condition for 30 days. Conclusion · Potassium-deficient culture can induce Mycobacterium tuberculosis at logarithmic phase into a dormant state.