Salt stress is one of the important adverse conditions affecting bacterium growth. How bacteria isolated from greenhouse soil cope with salt stress and regulate the genes responsible for salt tolerance are still unclear. We conducted RNA transcriptome profiling of genes contributing to the salt tolerance of a Bacillus sp. strain (“SX4”) obtained from salinized soil. Results showed that NaCl effectively regulated the growth of “SX4” in terms of cell length and colony-forming unit number decrease. A total of 121 upregulated and 346 downregulated genes were detected under salt stress with reference to the control. The largest numbers of differential expression genes were 17 in carbon metabolism, 13 in the biosynthesis of amino acids, 10 in a two-component system, and 10 in ABC transporter pathways for adapting to salt stress. Our data revealed that cation, electron and transmembrane transport, and catalytic activity play important roles in the resistance of bacterial cells to salt ions. Single-nucleotide polymorphism and the mutation of base pair T:A to C:G play potential roles in the adaptation of “SX4” to high NaCl concentrations. The findings from this study provide new insights into the molecular mechanisms of strain “SX4” and will be helpful in promoting the application of salt-tolerant bacteria.

中文翻译：

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氯化钠对芽孢杆菌耐盐性相关基因表达的影响。从盐渍温室土壤中分离出的“ SX4”菌株

盐胁迫是影响细菌生长的重要不利条件之一。从温室土壤中分离出来的细菌如何应对盐胁迫并调节负责耐盐性的基因仍不清楚。我们进行了基因的RNA转录组分析，这些基因有助于芽孢杆菌的耐盐性。盐化土壤中获得的菌株（“ SX4”）。结果表明，NaCl在细胞长度和集落形成单位数目减少方面有效地调节了“ SX4”的生长。参照对照，在盐胁迫下总共检测到121个上调的基因和346个下调的基因。差异表达基因最多的是碳代谢中的17个，氨基酸的生物合成中的13个，两组分系统中的10个和ABC转运蛋白途径中的10个，以适应盐胁迫。我们的数据表明，阳离子，电子和跨膜运输以及催化活性在细菌细胞对盐离子的抗性中起重要作用。单核苷酸多态性和碱基对T：A到C：G的突变在“ SX4”适应高NaCl浓度中起潜在作用。这项研究的发现为“ SX4”菌株的分子机制提供了新的见解，并将有助于促进耐盐细菌的应用。