中文摘要：

本研究旨在从分子水平探究细菌活的非可培养状态（VBNC）的发生机制。应用冰乙酸和4℃联合诱导条件，使鸡大肠杆菌进入VBNC状态，并利用mRNA差异显示技术（DDRT—PCR）获得VBNC相关基因。结果表明，从VBNC大肠杆菌中筛选得到的3个差异片段与大肠杆菌23S核糖体RNA基因序列具有较高的核苷酸同源性，分别为98％、98％和99％，而氨基酸的同源性也均在97％以上，表明这3个序列是大肠杆菌23S核糖体rRNA基因的部分序列，同时也是与大肠杆菌VBNC状态发生密切相关的基因。由此推知，当正常大肠杆菌在未暴露任何压力下时，其转录水平较低，特别是23SrRNA的某一（些）基因不显示或受到强烈抑制。当进入VBNC状态后，面临生存压力时，这一（些）基因转录水平明显强于正常状态，而核糖体作为蛋白质合成的主要结构与场所，其某些基因也将积极参与新蛋白质的生物合成。

英文摘要：

This experiment was conducted to study the molecular mechanisms of bacteria in viable but non-culturable （VBNC） state. Three differential fragments （A1, A2 and C1） were cloned from E. coli in VBNC induced by acetic acid and 4℃ with mRNA differential display PCR. These fragments were all extracted from E. coli in VBNC by reverse northern hybridization. The nucleotide homology between three sequences and E. coli 23S rRNA genes was 98%, 98% and 99%, respectively; and amino acids homology were all above 97%. These results indicated that normal E. coli without any selective pressure, its RNA transcript was lower, and some 23S rRNA genes were inhibited. But when in VBNC, some related genes expression were higher than that of normal state. These genes maybe participate in transcription or protein synthesis of E. coli in VBNC.