Rapid microevolution of biofilm cells in response to antibiotics

Anahit Penesyan; Stephanie S Nagy; Staffan Kjelleberg; Michael R Gillings; Ian T Paulsen

doi:10.1038/s41522-019-0108-3

Rapid microevolution of biofilm cells in response to antibiotics

NPJ Biofilms Microbiomes. 2019 Nov 6;5(1):34. doi: 10.1038/s41522-019-0108-3. eCollection 2019.

Authors

Anahit Penesyan^{1

2}, Stephanie S Nagy¹, Staffan Kjelleberg^{3

4

5}, Michael R Gillings⁶, Ian T Paulsen¹

Affiliations

¹ 1Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109 Australia.
² 2School of Chemical Engineering, University of New South Wales, Sydney, NSW 2052 Australia.
³ 3Singapore Centre for Environmental Life Sciences Engineering, 60 Nanyang Drive, SBS-01N-27, Singapore, 637551 Singapore.
⁴ 4School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore.
⁵ 5School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052 Australia.
⁶ 6Department of Biological Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109 Australia.

Abstract

Infections caused by Acinetobacter baumannii are increasingly antibiotic resistant, generating a significant public health problem. Like many bacteria, A. baumannii adopts a biofilm lifestyle that enhances its antibiotic resistance and environmental resilience. Biofilms represent the predominant mode of microbial life, but research into antibiotic resistance has mainly focused on planktonic cells. We investigated the dynamics of A. baumannii biofilms in the presence of antibiotics. A 3-day exposure of A. baumannii biofilms to sub-inhibitory concentrations of antibiotics had a profound effect, increasing biofilm formation and antibiotic resistance in the majority of biofilm dispersal isolates. Cells dispersing from biofilms were genome sequenced to identify mutations accumulating in their genomes, and network analysis linked these mutations to their phenotypes. Transcriptomics of biofilms confirmed the network analysis results, revealing novel gene functions of relevance to both resistance and biofilm formation. This approach is a rapid and objective tool for investigating resistance dynamics of biofilms.

Keywords: Antimicrobials; Biofilms.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acinetobacter baumannii / drug effects*
Acinetobacter baumannii / growth & development*
Anti-Bacterial Agents / metabolism*
Biofilms / drug effects*
Biofilms / growth & development*
Drug Resistance*
Drug Tolerance
Gene Expression Profiling
Whole Genome Sequencing

Substances

Anti-Bacterial Agents