| Title: | Thriving Under Stress: Pseudomonas aeruginosa Outcompetes the Background Polymicrobial Community Under Treatment Conditions in a Novel Chronic Wound Model |
| Author(s): | Phan J; Ranjbar S; Kagawa M; Gargus M; Hochbaum AI; Whiteson KL; |
| Address: | "Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States. Department of Chemical and Biomolecular Engineering, University of California, Irvine, Irvine, CA, United States. Department of Materials Science and Engineering, University of California, Irvine, Irvine, CA, United States. Department of Chemistry, University of California, Irvine, Irvine, CA, United States" |
| Journal Title: | Front Cell Infect Microbiol |
| DOI: | 10.3389/fcimb.2020.569685 |
| ISSN/ISBN: | 2235-2988 (Electronic) 2235-2988 (Linking) |
| Abstract: | "In vitro infection models are important for studying the effects of antimicrobials on microbial growth and metabolism. However, many models lack important biological components that resemble the polymicrobial nature of chronic wounds or infections. In this study, we developed a perfused meat model that supports the growth of the human pathogen Pseudomonas aeruginosa in a native meat microbial background to investigate the impact of antibiotics and hydrogen peroxide on polymicrobial community growth and metabolism. P. aeruginosa plays an important role as an etiological agent involved in chronic infections and is a common opportunistic pathogen. Chemical stressors in the form of hydrogen peroxide, carbenicillin, and gentamicin were perfused through the meat with polymicrobial growth on the surface. The relative abundances of P. aeruginosa and the background microbial community were analyzed by cell viability assays, and metabolic changes of the entire community in response to different antimicrobial treatments were characterized by GC-MS analysis of volatile organic compounds. The meat background community was characterized by amplicon sequencing. Relative densities of P. aeruginosa and background microbiota were similar under control conditions. Antimicrobial stressors, even at sub-inhibitory, physiologically relevant concentrations, spurred P. aeruginosa dominance of the meat surface community. Volatile metabolite ion intensity levels showed that antibacterial treatments drive changes in microbial metabolism. The abundance of the P. aeruginosa-derived metabolite, acetophenone, remained stable with treatment, whereas the relative abundances of 2-butanone, 2-nonanone, and 2-aminoacetophenone changed in response to treatment, suggesting these could serve as biomarkers of infection. Our model recapitulates some of the physiological conditions of chronic wounds and facilitates high throughput experiments without the high cost of in vivo models. Expanded use of this perfusion model will contribute to the understanding of polymicrobial growth and metabolism in the context of chronic wounds and infections" |
| Keywords: | Anti-Bacterial Agents/pharmacology *Anti-Infective Agents Humans *Microbiota *Pseudomonas Infections/drug therapy Pseudomonas aeruginosa antibiotics hydrogen peroxide polymicrobial volatile organic compound (VOC) wound model; |
| Notes: | "MedlinePhan, Joann Ranjbar, Saba Kagawa, Miki Gargus, Matthew Hochbaum, Allon Israel Whiteson, Katrine L eng Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. Switzerland 2020/10/31 Front Cell Infect Microbiol. 2020 Oct 6; 10:569685. doi: 10.3389/fcimb.2020.569685. eCollection 2020" |
