IBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal.
Departamento de Microbiologia, Laboratório de Microbiologia e Bioprocessos, Universidade Federal de Santa Catarina, Florianópolis, 88040-900, SC, Brazil.
Environ Microbiol. 2020 Apr;22(4):1341-1355. doi: 10.1111/1462-2920.14946. Epub 2020 Feb 23.
Numerous Pantoea strains are important because of the benefit they provide in the facilitation of plant growth. However, Pantoea have a high level of genotypic diversity and not much is understood regarding their ability to function in a plant beneficial manner. In the work reported here, the plant growth promotion activities and the genomic properties of the unusual Pantoea phytobeneficialis MSR2 are elaborated, emphasizing the genetic mechanisms involved in plant colonization and growth promotion. Detailed analysis revealed that strain MSR2 belongs to a rare group of Pantoea strains possessing an astonishing number of plant growth promotion genes, including those involved in nitrogen fixation, phosphate solubilization, 1-aminocyclopropane-1-carboxylic acid deaminase activity, indoleacetic acid and cytokinin biosynthesis, and jasmonic acid metabolism. Moreover, the genome of this bacterium also contains genes involved in the metabolism of lignin and other plant cell wall compounds, quorum-sensing mechanisms, metabolism of plant root exudates, bacterial attachment to plant surfaces and resistance to plant defences. Importantly, the analysis revealed that most of these genes are present on accessory plasmids that are found within a small subset of Pantoea genomes, reinforcing the idea that Pantoea evolution is largely mediated by plasmids, providing new insights into the evolution of beneficial plant-associated Pantoea.
许多 Pantoea 菌株因其促进植物生长的益处而显得尤为重要。然而，Pantoea 具有高度的基因型多样性，其在植物有益功能方面的能力还不太为人所知。在本报告的工作中，阐述了不寻常的植物有益 Pantoea phytobeneficialis MSR2 的植物生长促进活性及其基因组特性，强调了参与植物定殖和生长促进的遗传机制。详细分析表明，菌株 MSR2 属于 Pantoea 菌株的一个罕见群体，拥有惊人数量的植物生长促进基因，包括参与固氮、磷酸盐溶解、1-氨基环丙烷-1-羧酸脱氨酶活性、吲哚乙酸和细胞分裂素生物合成以及茉莉酸代谢的基因。此外，该细菌的基因组还包含与木质素和其他植物细胞壁化合物代谢、群体感应机制、植物根系分泌物代谢、细菌附着在植物表面以及对植物防御的抗性相关的基因。重要的是，分析表明，这些基因中的大多数存在于辅助质粒上，这些质粒存在于一小部分 Pantoea 基因组中，这进一步证实了 Pantoea 进化在很大程度上是由质粒介导的，为有益的植物相关 Pantoea 的进化提供了新的见解。
