de Souza Rafael Soares Correa, Armanhi Jaderson Silveira Leite, Damasceno Natália de Brito, Imperial Juan, Arruda Paulo
Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, Brazil.
Departamento de Genética e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil.
Front Microbiol. 2019 Aug 13;10:1779. doi: 10.3389/fmicb.2019.01779. eCollection 2019.
Despite the availability of data on the functional and phylogenetic diversity of plant-associated microbiota, the molecular mechanisms governing the successful establishment of plant bacterial communities remain mostly elusive. To investigate bacterial traits associated with successful colonization of plants, we sequenced the genome of 26 bacteria of a synthetic microbial community (SynCom), 12 of which displayed robust and 14 displayed non-robust colonization lifestyles when inoculated in maize plants. We examined the colonization profile of individual bacteria in inoculated plants and inspected their genomes for traits correlated to the colonization lifestyle. Comparative genomic analysis between robust and non-robust bacteria revealed that commonly investigated plant growth-promoting features such as auxin production, nitrogen (N) fixation, phosphate acquisition, and ACC deaminase are not deterministic for robust colonization. Functions related to carbon (C) and N acquisition, including transporters of carbohydrates and amino acids, and kinases involved in signaling mechanisms associated with C and N uptake, were enriched in robust colonizers. While enrichment of carbohydrate transporters was linked to a wide range of metabolites, amino acid transporters were primarily related to the uptake of branched-chain amino acids. Our findings identify diversification of nutrient uptake phenotypes in bacteria as determinants for successful bacterial colonization of plants.
尽管已有关于植物相关微生物群功能和系统发育多样性的数据，但控制植物细菌群落成功建立的分子机制仍大多不为人知。为了研究与植物成功定殖相关的细菌特性，我们对一个合成微生物群落（SynCom）中的26种细菌的基因组进行了测序，其中12种在接种到玉米植株时表现出强劲的定殖方式，14种表现出非强劲的定殖方式。我们检查了接种植物中单个细菌的定殖情况，并检查它们的基因组中与定殖方式相关的特性。对强劲定殖细菌和非强劲定殖细菌的比较基因组分析表明，通常研究的促进植物生长的特性，如生长素产生、固氮、磷获取和ACC脱氨酶，对于强劲定殖并非决定性因素。与碳（C）和氮（N）获取相关的功能，包括碳水化合物和氨基酸转运蛋白，以及参与与C和N摄取相关信号机制的激酶，在强劲定殖者中富集。虽然碳水化合物转运蛋白的富集与多种代谢物有关，但氨基酸转运蛋白主要与支链氨基酸的摄取有关。我们的研究结果确定了细菌中营养摄取表型的多样化是细菌成功定殖植物的决定因素。
