Galera Laporta, Letícia, 1985-García Ojalvo, Jordi2020-03-102020-03-102020Galera-Laporta L, Garcia-Ojalvo J. Antithetic population response to antibiotics in a polybacterial community. Science Advances. 2020; 6(10):eaaz5108. DOI: 10.1126/sciadv.aaz51082375-2548http://hdl.handle.net/10230/43845Much 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 Bacillus subtilis and Escherichia coli 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 B. subtilis is tolerant and E. coli is sensitive to ampicillin, in coculture it is E. coli who can proliferate in the presence of the antibiotic, while B. subtilis 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.application/pdfengCopyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial of License 4.0 (CC BY-NC).info:eu-repo/semantics/articlehttp://dx.doi.org/10.1126/sciadv.aaz5108info:eu-repo/semantics/openAccess