Azospirillum brasilense Sp245, a diazotrophic plant growth-promoting bacterium influences host plants via well-known mechanisms, gene interactions and confers abiotic and biotic stress tolerance mediated by signalling molecules. We present here, the functional characterization of a small RNA (sRNA), sSp_p6, identified from the 468 sRNAs identified in A. brasilense Sp245 and confirmed its involvement in nitrogen metabolism in the strain. sSp_p6 expression was found to be modulated in carbon and nitrogen stress while forming an interactive network with the target genes, vnfG (encoding vanadium-dinitrogenase) and σ-54 (sigma factor, interaction region) thereby establishing an essential role of this sRNA in biological nitrogen fixation by the strain. Additionally, upon inoculation with sSp_p6 overexpressing mutant, the host plant Sorghum exhibited increased lateral root formation, which led to improved plant root morphology.

巴西固氮螺菌SP245，通过公知的机构，基因相互作用并赋予非生物和生物胁迫耐受性通过信号分子介导的固氮植物生长促进细菌影响宿主植物。我们在这里介绍了小RNA（sRNA）sSp_p6的功能特征，该特征是从A. brasilense Sp245中鉴定的468个sRNA中鉴定出来的，并证实了其参与菌株的氮代谢。发现sSp_p6表达在碳和氮胁迫下受到调节，同时与靶基因vnfG形成相互作用网络（编码钒二氮合酶）和σ-54（σ因子，相互作用区域），从而确立该sRNA在菌株生物固氮中的重要作用。此外，接种过表达sSp_p6的突变体后，寄主植物高粱表现出增加的侧根形成，从而改善了植物根的形态。