CAREER: Redefining 'antimicrobial' in the context of microbe-chemical interactions indoors

Microbes are everywhere, including in indoor environments where they come into contact with humans. We use disinfectants and other antibiotics widely in these environments to combat disease-causing pathogens, which represent only a tiny fraction of microbial life. In spite of this diversity, antimicrobial chemicals are tested on just a handful of standard laboratory organisms.

The widespread use these chemicals can lead to the spread of antibiotic resistance, making antibiotics ineffective in fighting disease. This has led to antibiotic resistance being considered one of the biggest global public health challenges. It is thus critical to understand the impacts of antimicrobial chemicals on actual indoor microbes.

The goal of this CAREER project is to understand how chemicals and indoor microbes interact. This goal will be accomplished by looking at where microbe-chemical encounters happen in the and what happens to the microbes that survive these encounters. The results of this work have the potential to profoundly change the way we design and maintain indoor environments.

This work is tightly integrated with outreach to engage design professionals and the public about building materials, chemicals, and indoor microbes, and more broadly increase scientific literacy on this important global health issue.

The goal of this CAREER project is to use a multipronged approach to leverage molecular microbiology and analytical chemistry to arrive at a fundamental understanding of how chemicals and the indoor microbiome interact. The specific context in which this interaction will be evaluated is textiles. The overarching hypotheses are that 1) bioavailability of antimicrobial chemicals changes under environmental conditions and 2) exposure to antimicrobial chemicals changes bacterial community structure and function, including enrichment of antibiotic resistance.

To observe how bioavailability of antimicrobials in textiles is impacted by environmental conditions, antimicrobials such as nanosilver, nanozinc, and quaternary ammonium compounds will be identified and quantified using high resolution mass spectrometry under varying conditions. To test if antimicrobials in textiles alter the microbiome, reduced-complexity communities of undomesticated built environment bacteria will be exposed to antimicrobial materials.

Transcriptomic indicators and antibiotic resistance phenotypes will be measured. This work is tightly integrated with an outreach project to engage design professionals and the public about building materials, chemicals, and the indoor microbiome. Architects and designers will inform experimental design and dissemination of findings through interdisciplinary workshops, curriculum development, and continuing education units for architects.

Undergraduate and graduate students will be trained in science communication. Wikipedia edit-a-thons will be hosted to improve pages related to indoor environmental quality. Ultimately, this work will greatly advance our knowledge on how antimicrobial chemicals migrate out of building materials and shape the viability and antibiotic resistance of indoor bacterial communities.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.