Gorshkov Vladimir, Kwenda Stanford, Petrova Olga, Osipova Elena, Gogolev Yuri, Moleleki Lucy N
Kazan Institute of Biochemistry and Biophysics of Kazan Science Centre of Russian Academy of Sciences, Kazan, Russia.
Department of Biochemistry and Biotechnology, Kazan Federal University, Kazan, Russia.
PLoS One. 2017 Jan 12;12(1):e0169536. doi: 10.1371/journal.pone.0169536. eCollection 2017.
The ability to adapt to adverse conditions permits many bacterial species to be virtually ubiquitous and survive in a variety of ecological niches. This ability is of particular importance for many plant pathogenic bacteria that should be able to exist, except for their host plants, in different environments e.g. soil, water, insect-vectors etc. Under some of these conditions, bacteria encounter absence of nutrients and persist, acquiring new properties related to resistance to a variety of stress factors (cross-protection). Although many studies describe the phenomenon of cross-protection and several regulatory components that induce the formation of resistant cells were elucidated, the global comparison of the physiology of cross-protected phenotype and growing cells has not been performed. In our study, we took advantage of RNA-Seq technology to gain better insights into the physiology of cross-protected cells on the example of a harmful phytopathogen, Pectobacterium atrosepticum (Pba) that causes crop losses all over the world. The success of this bacterium in plant colonization is related to both its virulence potential and ability to persist effectively under various stress conditions (including nutrient deprivation) retaining the ability to infect plants afterwards. In our previous studies, we showed Pba to be advanced in applying different adaptive strategies that led to manifestation of cell resistance to multiple stress factors. In the present study, we determined the period necessary for the formation of cross-protected Pba phenotype under starvation conditions, and compare the transcriptome profiles of non-adapted growing cells and of adapted cells after the cross-protective effect has reached the maximal level. The obtained data were verified using qRT-PCR. Genes that were expressed differentially (DEGs) in two cell types were classified into functional groups and categories using different approaches. As a result, we portrayed physiological features that distinguish cross-protected phenotype from the growing cells.
适应不利条件的能力使许多细菌种类几乎无处不在，并能在各种生态位中生存。这种能力对许多植物致病细菌尤为重要，除了其宿主植物外，它们应该能够在不同的环境中生存，如土壤、水、昆虫载体等。在其中一些条件下，细菌会遇到营养物质缺乏的情况并持续存在，获得与对多种应激因素的抗性相关的新特性（交叉保护）。尽管许多研究描述了交叉保护现象，并且阐明了一些诱导抗性细胞形成的调控成分，但尚未对交叉保护表型和生长细胞的生理学进行全面比较。在我们的研究中，我们利用RNA测序技术，以一种有害的植物病原体——引起全球作物损失的黑胫果胶杆菌（Pba）为例，更好地了解交叉保护细胞的生理学。这种细菌在植物定殖方面的成功既与其致病潜力有关，也与其在各种应激条件（包括营养剥夺）下有效持续存在并随后保持感染植物的能力有关。在我们之前的研究中，我们表明Pba在应用不同的适应性策略方面很先进，这些策略导致细胞对多种应激因素产生抗性。在本研究中，我们确定了在饥饿条件下形成交叉保护的Pba表型所需的时间，并比较了未适应的生长细胞和交叉保护作用达到最大水平后的适应细胞的转录组图谱。使用qRT-PCR对获得的数据进行了验证。使用不同方法将在两种细胞类型中差异表达的基因（DEG）分类为功能组和类别。结果，我们描绘了区分交叉保护表型和生长细胞的生理特征。
