The bacterial community of childcare centers: potential implications for microbial dispersal and child exposure.

BACKGROUND: Bacterial communities within built environments reflect differences in sources of bacteria, building design, and environmental contexts. These communities impact the health of their occupants in many ways. Children interact with the built environment differently than do adults as a result of their unique behaviors, size, and developmental status. Consequently, understanding the broader bacterial community to which children are exposed will help inform public health efforts and contribute to our growing understanding of the bacterial community associated with childcare centers. METHODS: We sampled childcare centers to survey the variation in bacterial community composition across five surfaces found inside and outside twelve classrooms and six centers using 16S rRNA marker gene amplicon sequencing. We then correlated these bacterial community analyses of surfaces with environmental and demographic measures of illumination and classroom occupant density. RESULTS: The childcare environment was dominated by human-associated bacteria with modest input from outdoor sources. Though the bacterial communities of individual childcare centers differed, there was a greater difference in the bacterial community within a classroom than among centers. Surface habitats-fomites-within the classroom, did not differ in community composition despite differing proximity to likely sources of bacteria, and possible environmental filters, such as light. Bacterial communities did correlate with occupant density and differed significantly between high and low usage surfaces. CONCLUSIONS: Our results suggest built environments inhabited by young children are similar to functionally equivalent built environments inhabited by adults, despite the different way young children engage with their environment. Ultimately, these results will be useful when further interrogating microbial dispersal and human exposure to microorganisms in built environments that specifically cater to young children.

The role of citizen science in addressing grand challenges in food and agriculture research.

The power of citizen science to contribute to both science and society is gaining increased recognition, particularly in physics and biology. Although there is a long history of public engagement in agriculture and food science, the term 'citizen science' has rarely been applied to these efforts. Similarly, in the emerging field of citizen science, most new citizen science projects do not focus on food or agriculture. Here, we convened thought leaders from a broad range of fields related to citizen science, agriculture, and food science to highlight key opportunities for bridging these overlapping yet disconnected communities/fields and identify ways to leverage their respective strengths. Specifically, we show that (i) citizen science projects are addressing many grand challenges facing our food systems, as outlined by the United States National Institute of Food and Agriculture, as well as broader Sustainable Development Goals set by the United Nations Development Programme, (ii) there exist emerging opportunities and unique challenges for citizen science in agriculture/food research, and (iii) the greatest opportunities for the development of citizen science projects in agriculture and food science will be gained by using the existing infrastructure and tools of Extension programmes and through the engagement of urban communities. Further, we argue there is no better time to foster greater collaboration between these fields given the trend of shrinking Extension programmes, the increasing need to apply innovative solutions to address rising demands on agricultural systems, and the exponential growth of the field of citizen science.

The ecosystem services of animal microbiomes.

Microbiologists often evaluate microbial community dynamics by formulating functional hypotheses based on ecological processes. Indeed, many of the methods and terms currently used to describe animal microbiomes derive from ecology and evolutionary biology. As our understanding of the composition and functional dynamics of "the microbiome" grows, we increasingly refer to the host as an ecosystem within which microbial processes play out. Even so, an ecosystem service framework that extends to the context of the host has thus far been lacking. Here, we argue that ecosystem services are a useful framework with which to consider the value of microbes to their hosts. We discuss those "microbiome services" in the specific context of the mammalian gut, providing a context from which to develop new hypotheses and to evaluate microbial functions in future studies and novel systems.

Mycangia of ambrosia beetles host communities of bacteria.

The research field of animal and plant symbioses is advancing from studying interactions between two species to whole communities of associates. High-throughput sequencing of microbial communities supports multiplexed sampling for statistically robust tests of hypotheses about symbiotic associations. We focus on ambrosia beetles, the increasingly damaging insects primarily associated with fungal symbionts, which have also been reported to support bacteria. To analyze the diversity, composition, and specificity of the beetles' prokaryotic associates, we combine global sampling, insect anatomy, 454 sequencing of bacterial rDNA, and multivariate statistics to analyze prokaryotic communities in ambrosia beetle mycangia, organs mostly known for transporting symbiotic fungi. We analyze six beetle species that represent three types of mycangia and include several globally distributed species, some with major economic importance (Dendroctonus frontalis, Xyleborus affinis, Xyleborus bispinatus-ferrugineus, Xyleborus glabratus, Xylosandrus crassiusculus, and Xylosandrus germanus). Ninety-six beetle mycangia yielded 1,546 bacterial phylotypes. Several phylotypes appear to form the core microbiome of the mycangium. Three Mycoplasma (originally thought restricted to vertebrates), two Burkholderiales, and two Pseudomonadales are repeatedly present worldwide in multiple beetle species. However, no bacterial phylotypes were universally present, suggesting that ambrosia beetles are not obligately dependent on bacterial symbionts. The composition of bacterial communities is structured by the host beetle species more than by the locality of origin, which suggests that more bacteria are vertically transmitted than acquired from the environment. The invasive X. glabratus and the globally distributed X. crassiusculus have unique sets of bacteria, different from species native to North America. We conclude that the mycangium hosts in multiple vertically transmitted bacteria such as Mycoplasma, most of which are likely facultative commensals or parasites.