Transcriptome Analysis of Escherichia coli Dormant Cystlike Cells

— The transcriptome of Esherichia coli cystlike dormant cells was investigated. RNA content in a single dormant cell was 0.26 fg, i.e., 13.5 times less than in a cell of a growing culture. The presence of mRNA in E. coli dormant cells has not been reported previously. The pools of gene reads for the dormant and growing cells were characterized, as well as the differential expression of all genes, calculated according to the special algorithm considering the average mRNA amount in a single cell. The notion of the genes active in every cell of the population was introduced. In each cell of the dormant and growing E. coli population, such genes were represented by the transcripts of 21 and 16% of the genes, respectively. The revealed cell heterogeneity regarding set of active genes is one of the reasons (and forms) of heterogeneity of bacterial populations. Sixty genes were revealed, for which activity increased twice or more during formation of E. coli dormant cells. These were the genes responsible for genome activity, structure and properties of the cell envelope, cell proliferation, stress adaptation, biofilm formation and functioning, and collective behavior, as well as the genes providing for survival of the cell population during germination of the dormant cells.