Abstract:
The gut microbiome plays a fundamental role in metabolism, as well as the immune and nervous systems. Microbial imbalance (dysbiosis) can contribute to subsequent physical and mental pathologies. As such, interest has been growing in the microbiota-gut-brain brain axis and the bioelectrical communication that could exist between bacterial and nervous cells. The aim of this study was to investigate the bioelectrical profile (electrome) of two bacterial species characteristic of the gut microbiome: a Proteobacteria Gram-negative bacillus Escherichia coli (E. coli), and a Firmicutes Gram-positive coccus Enterococcus faecalis (E. faecalis). We analyzed both bacterial strains to (i) validate the fluorescent probe bis-(1,3-dibutylbarbituric acid) trimethine oxonol, DiBAC4(3), as a reliable reporter of the changes in membrane potential (Vmem) for both bacteria; (ii) assess the evolution of the bioelectric profile throughout the growth of both strains; (iii) investigate the effects of two neural-type stimuli on Vmem changes: the excitatory neurotransmitter glutamate (Glu) and the inhibitory neurotransmitter γ-aminobutyric acid (GABA); (iv) examine the impact of the bioelectrical changes induced by neurotransmitters on bacterial growth, viability, and cultivability using absorbance, live/dead fluorescent probes, and viable counts, respectively. Our findings reveal distinct bioelectrical profiles characteristic of each bacterial species and growth phase. Importantly, neural-type stimuli induce Vmem changes without affecting bacterial growth, viability, or cultivability, suggesting a specific bioelectrical response in bacterial cells to neurotransmitter cues. These results contribute to understanding the bacterial response to external stimuli, with potential implications for modulating bacterial bioelectricity as a novel therapeutic target.
摘要:
肠道微生物在新陈代谢中起着重要的作用,以及免疫系统和神经系统。微生物失衡(菌群失调)可能导致随后的身体和精神疾病。因此,人们对微生物群-肠-脑-脑轴以及细菌和神经细胞之间可能存在的生物电通信越来越感兴趣。这项研究的目的是研究肠道微生物组特有的两种细菌的生物电谱(electromme):革兰氏阴性杆菌大肠杆菌(E.大肠杆菌),和Firmicutes革兰氏阳性球菌粪肠球菌(E.粪肠)。我们分析了两种细菌菌株,以(i)验证荧光探针双-(1,3-二丁基巴比妥酸)三甲胺氧杂酚,DiBAC4(3),作为两种细菌膜电位(Vmem)变化的可靠报道者;(ii)评估两种菌株在整个生长过程中生物电谱的演变;(iii)研究两种神经型刺激对Vmem变化的影响:兴奋性神经递质谷氨酸(Glu)和抑制性神经递质γ-氨基丁酸(GABA);(iv)检查神经递质诱导的生物电变化对细菌生长的影响,生存能力,和利用吸光度的可栽培性,活/死荧光探针,和可行的计数,分别。我们的发现揭示了每种细菌种类和生长期的独特生物电特征。重要的是,神经型刺激诱导Vmem变化而不影响细菌生长,生存能力,或可培养性,提示细菌细胞对神经递质线索的特定生物电反应。这些结果有助于理解细菌对外界刺激的反应,具有调节细菌生物电作为新的治疗靶标的潜在意义。