Geography of Microbiomes

The United States is a unique place, and each city has its own character and personality. They all look different and contain different people. Just like each city is different from those around it, the microbial content of the city is also unique. This microscopic environment has its own pattern and life which makes it distinct from other cities.

Researchers from Northern Arizona University took samples from Flagstaff, San Diego, and Toronto and analyzed the samples. Each city has a climate that it different from the other ones, which can influence the kinds of microbes that can grow. Samples were taken on surfaces like carpet, tile, or ceiling, and factors like humidity and temperature were accounted for. Bacteria, protists, and fungi were found which were unique to each city and office environment, but the microbial life was similar in each office in a particular city.

Previous research has confirmed the findings of this study. Researchers thought that they might find different microbes in office environments that were hotter or more humid than others, but found remarkably similar microbial climates in each city. Geography seemed to be the most influential factor in determining what kinds of microbial life would be found in a variety of local settings.

(a) Configuration of sampling site in Flagstaff office 1. This configuration was similar to those set up in all offices. Signs on the wall adjacent to wall sampling plate describe the project, as request that the materials not be touched. (b) Diagram of single sampling plate illustrating nine sampling swatches (circles) of three different materials, one row for tracking equilibrium relative humidity of the materials (Row #1), one row for infrequent sampling (Row #2), and one row for frequent sampling (Row #3). (c) Samples were collected from rows 2 and 3 of all sampling plates from three offices in each of our three cities in four intensive sampling periods over the course of one year. Coloring of sampling swatches in this figure illustrates the change in bacterial Phylogenetic Diversity over the year.

(a) Configuration of sampling site in Flagstaff office 1. This configuration was similar to those set up in all offices. Signs on the wall adjacent to wall sampling plate describe the project, as request that the materials not be touched. (b) Diagram of single sampling plate illustrating nine sampling swatches (circles) of three different materials, one row for tracking equilibrium relative humidity of the materials (Row #1), one row for infrequent sampling (Row #2), and one row for frequent sampling (Row #3). (c) Samples were collected from rows 2 and 3 of all sampling plates from three offices in each of our three cities in four intensive sampling periods over the course of one year. Coloring of sampling swatches in this figure illustrates the change in bacterial Phylogenetic Diversity over the year. From Chase el al, 2016.

Research of this kind could help track the evolution of microbes as well as determine where people have travelled. Each person would have a unique microbiome around them based on where they have been, and if there was a database created for cities in the world, researchers could theoretically track where people have been down to the city level.

Each microbiome is influenced by geography and climate, and anyone or anything that travels through that climate (both indoors and outside) is changed by that microbiome. Microscopic organisms can stick to animal’s fur, the bottom of people’s shoes and even come in the air we breathe. All these factors can lead to a microscopic trail of where we’ve been.

More:

Chase JH, Fouquier J, Zare M, Sonderegger DL, Knight R, Kelley S, Siegel JA, Caporaso JG. (2016Geography and location are the primary drivers of office microbiome compositionPeerJ Preprints 4:e1797v1 https://doi.org/10.7287/peerj.preprints.1797v1

Cities Have Unique Microbial Signatures, New Study Says, Motherboard, April 19, 2016.