Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, Dr. Aiguader 88, 08003 Barcelona, Spain.
Sci Adv. 2020 Mar 6;6(10):eaaz5108. doi: 10.1126/sciadv.aaz5108. eCollection 2020 Mar.
Much is known about the effects of antibiotics on isolated bacterial species, but their influence on polybacterial communities is less understood. Here, we study the joint response of a mixed community of nonresistant and bacteria to moderate concentrations of the β-lactam antibiotic ampicillin. We show that when the two organisms coexist, their population response to the antibiotic is opposite to that in isolation: Whereas in monoculture is tolerant and is sensitive to ampicillin, in coculture it is who can proliferate in the presence of the antibiotic, while cannot. This antithetic behavior is predicted by a mathematical model constrained only by the responses of the two species in isolation. Our results thus show that the collective response of mixed bacterial ecosystems to antibiotics can run counter to what single-species potency studies tell us about their efficacy.
关于抗生素对分离细菌物种的影响已经有很多了解，但它们对多细菌群落的影响还不太清楚。在这里，我们研究了非耐药 和 细菌混合群落对中等浓度β-内酰胺类抗生素氨苄青霉素的联合反应。我们表明，当两种生物共存时，它们对抗生素的种群反应与单独培养时相反：在单一培养中， 对氨苄青霉素具有耐受性，而 对氨苄青霉素敏感，而在共培养中，能够在抗生素存在的情况下增殖的是 ，而 则不能。这种对偶行为仅由两种物种在单独培养中的反应所约束的数学模型预测。因此，我们的结果表明，混合细菌生态系统对抗生素的集体反应可能与关于其功效的单种效力研究告诉我们的情况相反。
