To determine microbial evolutionary strategies to low-pressure (LP; 5 kPa) growth, an environmental condition not experienced on Earth until ∼20 km in altitude, a previously described evolutionary experiment was conducted. The resulting LP evolved strain WN1106, isolated from the terminus of the experiment, was shown to have several genomic mutations absent in the ancestral strain, WN624. Three of the mutations were in regulatory genes: resD, walK, and rnjB. Here we report on transcriptional microarray data from the LP-evolved WN1106 and compare those results with the previously reported ancestral WN624 transcriptional array data at either 5 or 101 kPa. At 5 kPa, WN1106 differentially expresses signals that are under the control of regulators ResD, WalK, and RnjB compared with (1) itself at ∼101 kPa and (2) WN624 at 5 kPa. These results were further confirmed by quantitative reverse transcriptase–polymerase chain reaction of a target transcript from each regulon. This work indicates that the three mutated coding regions had transcriptional control effects on each respective regulon.

中文翻译：

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5 kPa 下的生长导致枯草芽孢杆菌菌株中许多信号的差异表达，该菌株适应于低压下的增强生长

为了确定低压 (LP; 5 kPa) 生长的微生物进化策略，地球上直到海拔约 20 公里才经历过这种环境条件，进行了先前描述的进化实验。从实验终点分离的所得 LP 进化菌株 WN1106 显示出在祖先菌株 WN624 中不存在几个基因组突变。其中三个突变发生在调控基因中：resD、walK和rnjB. 在这里，我们报告了来自 LP 进化的 WN1106 的转录微阵列数据，并将这些结果与先前报道的 5 或 101 kPa 的祖先 WN624 转录阵列数据进行了比较。在 5 kPa 时，WN1106 差异表达受调节器 ResD、WalK 和 RnjB 控制的信号，与（1）自身在 101 kPa 时和（2）WN624 在 5 kPa 时相比。这些结果通过来自每个调节子的目标转录物的定量逆转录酶-聚合酶链反应得到进一步证实。这项工作表明三个突变的编码区对每个相应的调节子都有转录控制作用。