PDF(Pubmed)
Abstract：
Soil is an environment with numerous niches, where bacteria are exposed to diverse conditions. Some bacteria are exposed earlier than others to pressure, and the emission of signals that other bacteria can receive and perceive may allow a better response to an eminent stimulus. To shed light on how bacteria trigger their response and adapt to changes in the environment, the intra- and interspecific influences of volatiles on bacterial strains growing under non-stressed and cadmium-stressed conditions were assessed. Each strain was exposed to its volatiles emitted by cells growing under different conditions to test whether the environment in which a cell grows influences neighboring cells. The five genera tested showed different responses, with Rhizobium displaying the greatest influence. In a second experiment, 13 strains from different genera were grown under control conditions but exposed to volatiles released by Cd-stressed Rhizobium cells to ascertain whether Rhizobium\'s observed influence was strain-specific or broader. Our results showed that the volatiles emitted by some bacteria under stress are differentially perceived and translated into biochemical changes (growth, alteration of the antioxidant response, and oxidative damage) by other bacteria, which may increase the adaptability and resilience of bacterial communities to environmental changes, especially those with a prooxidant nature. Cadmium (Cd) contamination of soils constitutes a risk to the environment and human health. Here, we showed the effects of Cd exposure on bacteria and how volatile communication influences the biochemistry related to coping with oxidative stress. This knowledge can be important for remediation and risk assessment and highlights that new biological features, such as volatile communication, should be considered when studying and assessing the impact of contaminants on soil ecosystems.
摘要：
土壤是一个拥有众多生态位的环境，细菌暴露在不同的条件下。一些细菌比其他细菌更早暴露在压力下，其他细菌可以接收和感知的信号的发射可能会对突出的刺激产生更好的反应。为了阐明细菌如何触发其反应并适应环境变化，评估了挥发物对在非胁迫和镉胁迫条件下生长的细菌菌株的种内和种间影响。将每个菌株暴露于在不同条件下生长的细胞释放的挥发物，以测试细胞生长的环境是否影响相邻细胞。测试的五个属显示出不同的反应，根瘤菌表现出最大的影响。在第二个实验中,来自不同属的13个菌株在对照条件下生长，但暴露于Cd胁迫的根瘤菌细胞释放的挥发物，以确定根瘤菌观察到的影响是否是菌株特异性的或更广泛的。我们的结果表明，某些细菌在压力下释放的挥发物被不同地感知并转化为生化变化（生长，抗氧化反应的改变，和氧化损伤)被其他细菌，这可能会增加细菌群落对环境变化的适应性和复原力，尤其是那些具有促氧化剂性质的。土壤中的镉（Cd）污染对环境和人类健康构成了风险。这里,我们展示了Cd暴露对细菌的影响以及挥发性通讯如何影响与应对氧化应激相关的生物化学。这些知识对于补救和风险评估可能很重要，并强调新的生物学特征，例如易失性通信，在研究和评估污染物对土壤生态系统的影响时应予以考虑。
