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bioRxiv · 10.1101/676148

The Molecular and Microbial Microenvironments in Chronically Diseased Lungs

Abstract

To visualize the personalized distributions of pathogens, chemical environments including microbial metabolites, pharmaceuticals, and their metabolic products within and between human lungs afflicted with cystic fibrosis, we generated 3D microbiome and metabolome maps of six explanted lungs from three cystic fibrosis patients. These 3D spatial maps revealed that the chemical environments are variable between patients and within the lungs of each patient. Although the patients microbial ecosystems were defined by the dominant pathogen, their chemical diversity was not. Additionally, the chemical diversity between locales in lungs of the same individual sometimes exceeded inter-individual variation. Thus, the chemistry and microbiome of the explanted lungs appear to be not only personalized but also regiospecific. Previously undescribed analogs of microbial quinolones and antibiotic metabolites were also detected. Furthermore, mapping the chemical and microbial distributions allowed visualization of microbial community interactions, such as increased production of quorum sensing quinolones in locations where Pseudomonas was in contact with Staphylococcus and Granulicatella, consistent with in vitro observations of bacteria isolated from these patients. Visualization of microbe-metabolite associations within a host organ in early-stage CF disease in animal models will help elucidate a complex interplay between the presence of a given microbial structure, antibiotics, metabolism of antibiotics, microbial virulence factors, and host responses.\n\nImportanceMicrobial infections are now recognized to be polymicrobial and personalized in nature. A comprehensive analysis and understanding of the factors underlying the polymicrobial and personalized nature of infections remains limited, especially in the context of the host. By visualizing microbiomes and metabolomes of diseased human lungs, we describe how different the chemical environments are between hosts that are dominated by the same pathogen and how community interactions shape the chemical environment, or vice versa. We highlight that three-dimensional organ mapping are hypothesis building tools that allow us to design mechanistic studies aimed at addressing microbial responses to other microbes, the host, and pharmaceutical drugs.

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BibTeXRIS

Garg, N., Melnik, A. V., Vasquez-Baeza, Y., Aksenov, A., Hyde, E. R., McAvoy, A. C., Wang, M., da Silva, R., Protsyuk, I., Wu, J. V., Bouslimani, A., Lim, Y. W., Luzzatto-Knaan, T., Comstock, W., Quinn, R. A., Wong, R., Humphrey, G., Ackermann, G., Spivey, T., Brouha, S. S., Bandeira, N., Lin, G. Y., Rohwer, F., Conrad, D., Alexandrov, T., Dorrestein, P. C., Knight, R.. 2019-06-19. The Molecular and Microbial Microenvironments in Chronically Diseased Lungs. https://doi.org/10.1101/676148

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