Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, PR China; Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, PR China.
Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, PR China.
Biochem Biophys Res Commun. 2018 Sep 5;503(2):784-790. doi: 10.1016/j.bbrc.2018.06.076. Epub 2018 Jun 18.
Nitric oxide (NO) is an important gas signal that regulates many biological processes, and due to the high nitrogen recycling activity in the rhizosphere, NO is an important signaling molecule in this region. Thus, an understanding of the effect of NO on the rhizomicrobiome, especially on plant beneficial rhizobacteria, is important for the use of these bacteria in agriculture. In this study, the effect of exogenous NO on the beneficial rhizobacterium Bacillus amyloliquefaciens SQR9 was investigated. The results showed that low concentrations of NO increased the ability of the strain SQR9 to form biofilms, while high concentrations of NO inhibited the growth of this bacterium. The SQR9 gene yflM encodes nitric oxide synthase (NOS), which is used to synthesize NO, while the gene ykvO encodes a sepiapterin reductase that is used to synthesize tetrahydrobiopterin, the coenzyme of NOS. Isothermal titration calorimetry and high-performance liquid chromatography analyses demonstrated an interaction between YkvO and NADPH. SQR9 has two hmp genes, although only one was observed to be responsible for NO detoxification through oxidization. This study revealed the effect of NO on plant beneficial rhizobacterium and assessed the ability of this strain to adapt to exogenous NO, which will help to improve the application of this strain in agricultural production.
一氧化氮（NO）是一种重要的气体信号分子，调节着许多生物过程，由于根际具有高氮循环活性，因此 NO 是该区域的重要信号分子。因此，了解 NO 对根际微生物组的影响，特别是对植物有益根际细菌的影响，对于这些细菌在农业中的应用是很重要的。本研究探讨了外源 NO 对有益根际细菌解淀粉芽孢杆菌 SQR9 的影响。结果表明，低浓度的 NO 可提高菌株 SQR9 形成生物膜的能力，而高浓度的 NO 则抑制该细菌的生长。SQR9 基因 yflM 编码一氧化氮合酶（NOS），用于合成 NO，而基因 ykvO 编码一种四氢生物蝶呤还原酶，用于合成 NOS 的辅酶四氢生物蝶呤。等温滴定量热法和高效液相色谱分析表明 YkvO 与 NADPH 之间存在相互作用。SQR9 有两个 hmp 基因，但只有一个被观察到通过氧化作用来解毒 NO。本研究揭示了 NO 对植物有益根际细菌的影响，并评估了该菌株适应外源 NO 的能力，这将有助于提高该菌株在农业生产中的应用。
