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Microbial biogeography of a university campus.

Ross AA, Neufeld JD - Microbiome (2015)

Bottom Line: Although inter-handle variability was high, several individual building entrances harbored distinct microbial communities that were consistent over time.The presence of visible environmental debris on a subset of handles was associated with distinct microbial communities (beta diversity), increased richness (alpha diversity), and higher biomass (adenosine 5'-triphosphate; ATP).Nonetheless, the data also revealed several building-specific and temporally stable bacterial and archaeal community patterns, with a potential impact of accumulated debris, a possible result of low human throughput, on detected microbial communities.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. aaross@uwaterloo.ca.

ABSTRACT

Background: Microorganisms are distributed on surfaces within homes, workplaces, and schools, with the potential to impact human health and disease. University campuses represent a unique opportunity to explore the distribution of microorganisms within built environments because of high human population densities, throughput, and variable building usage. For example, the main campus of the University of Waterloo spans four square kilometres, hosts over 40,000 individuals daily, and is comprised of a variety of buildings, including lecture halls, gyms, restaurants, residences, and a daycare.

Results: Representative left and right entrance door handles from each of the 65 buildings at the University of Waterloo were swabbed at three time points during an academic term in order to determine if microbial community assemblages coincided with building usage and whether these communities are stable temporally. Across all door handles, the dominant phyla were Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes, which comprised 89.0 % of all reads. A total of 713 genera were observed, 16 of which constituted a minimum of 1 % of the 2,458,094 classified and rarefied reads. Archaea were found in low abundance (~0.03 %) but were present on 42.8 % of the door handles on 96 % of buildings across all time points, indicating that they are ubiquitous at very low levels on door handle surfaces. Although inter-handle variability was high, several individual building entrances harbored distinct microbial communities that were consistent over time. The presence of visible environmental debris on a subset of handles was associated with distinct microbial communities (beta diversity), increased richness (alpha diversity), and higher biomass (adenosine 5'-triphosphate; ATP).

Conclusions: This study demonstrates highly variable microbial communities associated with frequently contacted door handles on a university campus. Nonetheless, the data also revealed several building-specific and temporally stable bacterial and archaeal community patterns, with a potential impact of accumulated debris, a possible result of low human throughput, on detected microbial communities.

No MeSH data available.


Related in: MedlinePlus

Diversity of the 65 university campus buildings. a The average number of OTUs observed for each building. Each point consists of up to six samples, with two per sample date. Error bars represent the standard deviation. b Shannon index for each door, organized by building. Blue points represent swabs that were associated with visible debris, whereas red points indicate swabs without debris. The bottom row is color coded according to the faculty or specific campus function of the building
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Fig3: Diversity of the 65 university campus buildings. a The average number of OTUs observed for each building. Each point consists of up to six samples, with two per sample date. Error bars represent the standard deviation. b Shannon index for each door, organized by building. Blue points represent swabs that were associated with visible debris, whereas red points indicate swabs without debris. The bottom row is color coded according to the faculty or specific campus function of the building

Mentions: The number of OTUs on door handles ranged from 221 to 1450 (Fig. 3a). The building with the lowest average number of OTUs was the Tutor House (TH) student townhouses, whereas the building with the most OTUs was the Physical Activities Complex (PAC). In particular, the PAC had the most OTUs during time point 2 when a student convocation event was occurring inside. Samples from this time point had an average of 754 more OTUs than all other samples from all sampling dates and an average of 393 more OTUs than PAC door handles from the remaining sampling dates (Additional file 1: Table S1). Because convocation brings thousands of visitors to the university, and the PAC in particular, we predict that increased student throughput and the presence of visitors who do not normally contact door handles on campus provides a reasonable explanation for the increase in diversity observed on the PAC door handles at this time. This finding was reinforced by the adjacent Student Life Centre (SLC) building, which is also used during convocation events. The SLC had an average of 319 more OTUs during convocation than the SLC door handles from the remaining sampling dates and 140 more OTUs than all other door handle samples from all sampling dates.Fig. 3


Microbial biogeography of a university campus.

Ross AA, Neufeld JD - Microbiome (2015)

Diversity of the 65 university campus buildings. a The average number of OTUs observed for each building. Each point consists of up to six samples, with two per sample date. Error bars represent the standard deviation. b Shannon index for each door, organized by building. Blue points represent swabs that were associated with visible debris, whereas red points indicate swabs without debris. The bottom row is color coded according to the faculty or specific campus function of the building
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4666157&req=5

Fig3: Diversity of the 65 university campus buildings. a The average number of OTUs observed for each building. Each point consists of up to six samples, with two per sample date. Error bars represent the standard deviation. b Shannon index for each door, organized by building. Blue points represent swabs that were associated with visible debris, whereas red points indicate swabs without debris. The bottom row is color coded according to the faculty or specific campus function of the building
Mentions: The number of OTUs on door handles ranged from 221 to 1450 (Fig. 3a). The building with the lowest average number of OTUs was the Tutor House (TH) student townhouses, whereas the building with the most OTUs was the Physical Activities Complex (PAC). In particular, the PAC had the most OTUs during time point 2 when a student convocation event was occurring inside. Samples from this time point had an average of 754 more OTUs than all other samples from all sampling dates and an average of 393 more OTUs than PAC door handles from the remaining sampling dates (Additional file 1: Table S1). Because convocation brings thousands of visitors to the university, and the PAC in particular, we predict that increased student throughput and the presence of visitors who do not normally contact door handles on campus provides a reasonable explanation for the increase in diversity observed on the PAC door handles at this time. This finding was reinforced by the adjacent Student Life Centre (SLC) building, which is also used during convocation events. The SLC had an average of 319 more OTUs during convocation than the SLC door handles from the remaining sampling dates and 140 more OTUs than all other door handle samples from all sampling dates.Fig. 3

Bottom Line: Although inter-handle variability was high, several individual building entrances harbored distinct microbial communities that were consistent over time.The presence of visible environmental debris on a subset of handles was associated with distinct microbial communities (beta diversity), increased richness (alpha diversity), and higher biomass (adenosine 5'-triphosphate; ATP).Nonetheless, the data also revealed several building-specific and temporally stable bacterial and archaeal community patterns, with a potential impact of accumulated debris, a possible result of low human throughput, on detected microbial communities.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. aaross@uwaterloo.ca.

ABSTRACT

Background: Microorganisms are distributed on surfaces within homes, workplaces, and schools, with the potential to impact human health and disease. University campuses represent a unique opportunity to explore the distribution of microorganisms within built environments because of high human population densities, throughput, and variable building usage. For example, the main campus of the University of Waterloo spans four square kilometres, hosts over 40,000 individuals daily, and is comprised of a variety of buildings, including lecture halls, gyms, restaurants, residences, and a daycare.

Results: Representative left and right entrance door handles from each of the 65 buildings at the University of Waterloo were swabbed at three time points during an academic term in order to determine if microbial community assemblages coincided with building usage and whether these communities are stable temporally. Across all door handles, the dominant phyla were Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes, which comprised 89.0 % of all reads. A total of 713 genera were observed, 16 of which constituted a minimum of 1 % of the 2,458,094 classified and rarefied reads. Archaea were found in low abundance (~0.03 %) but were present on 42.8 % of the door handles on 96 % of buildings across all time points, indicating that they are ubiquitous at very low levels on door handle surfaces. Although inter-handle variability was high, several individual building entrances harbored distinct microbial communities that were consistent over time. The presence of visible environmental debris on a subset of handles was associated with distinct microbial communities (beta diversity), increased richness (alpha diversity), and higher biomass (adenosine 5'-triphosphate; ATP).

Conclusions: This study demonstrates highly variable microbial communities associated with frequently contacted door handles on a university campus. Nonetheless, the data also revealed several building-specific and temporally stable bacterial and archaeal community patterns, with a potential impact of accumulated debris, a possible result of low human throughput, on detected microbial communities.

No MeSH data available.


Related in: MedlinePlus