Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdańsk, ul. A. Abrahama 58, 80-307, Gdańsk, Poland.
Laboratory of Structural Biochemistry, Faculty of Chemistry, University of Gdańsk, ul. Wita Stwosza 63, 80-308, Gdańsk, Poland.
Sci Rep. 2023 Jun 9;13(1):9445. doi: 10.1038/s41598-023-36494-6.
Pseudomonads are metabolically flexible and can thrive on different plant hosts. However, the metabolic adaptations required for host promiscuity are unknown. Here, we addressed this knowledge gap by employing RNAseq and comparing transcriptomic responses of Pseudomonas donghuensis P482 to root exudates of two plant hosts: tomato and maize. Our main goal was to identify the differences and the common points between these two responses. Pathways upregulated only by tomato exudates included nitric oxide detoxification, repair of iron-sulfur clusters, respiration through the cyanide-insensitive cytochrome bd, and catabolism of amino and/or fatty acids. The first two indicate the presence of NO donors in the exudates of the test plants. Maize specifically induced the activity of MexE RND-type efflux pump and copper tolerance. Genes associated with motility were induced by maize but repressed by tomato. The shared response to exudates seemed to be affected both by compounds originating from the plants and those from their growth environment: arsenic resistance and bacterioferritin synthesis were upregulated, while sulfur assimilation, sensing of ferric citrate and/or other iron carriers, heme acquisition, and transport of polar amino acids were downregulated. Our results provide directions to explore mechanisms of host adaptation in plant-associated microorganisms.
假单胞菌具有代谢灵活性，可以在不同的植物宿主上茁壮成长。然而，宿主混杂所需的代谢适应机制尚不清楚。在这里，我们通过 RNAseq 并比较了 Pseudomonas donghuensis P482 对两种植物宿主（番茄和玉米）根分泌物的转录组反应，来解决这一知识空白。我们的主要目标是确定这两种反应之间的差异和共同点。仅由番茄分泌物上调的途径包括一氧化氮解毒、铁硫簇的修复、通过氰化物不敏感细胞色素 bd 进行呼吸作用，以及氨基酸和/或脂肪酸的分解代谢。前两个途径表明测试植物分泌物中存在氮氧化物供体。玉米特异性诱导 MexE RND 型外排泵和铜耐受性的活性。与运动性相关的基因受玉米诱导，但受番茄抑制。对分泌物的共同反应似乎受到植物及其生长环境中化合物的共同影响：砷抗性和菌铁蛋白合成上调，而硫同化、铁柠檬酸和/或其他铁载体的感应、卟啉的获取以及极性氨基酸的运输则下调。我们的研究结果为探索植物相关微生物中宿主适应的机制提供了方向。
