American Gut: an Open Platform for Citizen Science Microbiome Research

McDonald D, Hyde E, Debelius JW, et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3(3):e00031-18

Effects of imidacloprid on the ability of honey bee foragers to distinguish safe and unsafe food sources

Pesticides can harm honey bee health and foraging behavior, even when bees are exposed to sublethal doses. We tested the effect of imidacloprid, a common neonicotinoid pesticide, on honey bee avoidance of danger during foraging in indoor and outdoor feeder choice trials. Danger stimuli consisted of honey bee sting gland alarm pheromone or live praying mantises. In outdoor foraging experiments in which bees chose between two feeders, bees fed repeatedly upon sucrose solution containing a high but field-realistic concentration of 40 μg/L imidacloprid. However, there was no effect of pesticide treatment. Neither pesticide nor control bees demonstrated significant avoidance of the live mantis (P≥0.63 for non pesticide bees and P≥0.42 for pesticide bees). In contrast, control bees avoided the alarm pheromone feeder in all three consecutive choices (P≤0.01). Pesticide-treated bees avoided the alarm pheromone feeder only on their second choice (P=0.004). There was no significant overall effect of pesticide treatment in this experiment. In indoor trials designed to mimic outdoor foraging under controlled conditions, bees exposed to 1 ng or 2.16 ng of imidacloprid spent 16-26% less time on the side of the indoor arena with alarm pheromone as compared to control bees. These trials possibly presented a different context: bees attempting to escape rather than forage. Overall, our results do not provide strong support for the hypothesis that imidacloprid alters bee decision-making about danger in the context of foraging, though the indoor trials suggest a new avenue of investigation into the effects of imidacloprid on honey bee escape behavior

Effects of imidacloprid on the ability of honey bee foragers to distinguish safe and unsafe food sources

Pesticides can harm honey bee health and foraging behavior, even when bees are exposed to sublethal doses. We tested the effect of imidacloprid, a common neonicotinoid pesticide, on honey bee avoidance of danger during foraging in indoor and outdoor feeder choice trials. Danger stimuli consisted of honey bee sting gland alarm pheromone or live praying mantises. In outdoor foraging experiments in which bees chose between two feeders, bees fed repeatedly upon sucrose solution containing a high but field-realistic concentration of 40 μg/L imidacloprid. However, there was no effect of pesticide treatment. Neither pesticide nor control bees demonstrated significant avoidance of the live mantis (P≥0.63 for non pesticide bees and P≥0.42 for pesticide bees). In contrast, control bees avoided the alarm pheromone feeder in all three consecutive choices (P≤0.01). Pesticide-treated bees avoided the alarm pheromone feeder only on their second choice (P=0.004). There was no significant overall effect of pesticide treatment in this experiment. In indoor trials designed to mimic outdoor foraging under controlled conditions, bees exposed to 1 ng or 2.16 ng of imidacloprid spent 16-26% less time on the side of the indoor arena with alarm pheromone as compared to control bees. These trials possibly presented a different context: bees attempting to escape rather than forage. Overall, our results do not provide strong support for the hypothesis that imidacloprid alters bee decision-making about danger in the context of foraging, though the indoor trials suggest a new avenue of investigation into the effects of imidacloprid on honey bee escape behavior

High-Resolution Longitudinal Dynamics of the Cystic Fibrosis Sputum Microbiome and Metabolome through Antibiotic Therapy.

Microbial diversity in the cystic fibrosis (CF) lung decreases over decades as pathogenic bacteria such as Pseudomonas aeruginosa take over. The dynamics of the CF microbiome and metabolome over shorter time frames, however, remain poorly studied. Here, we analyze paired microbiome and metabolome data from 594 sputum samples collected over 401 days from six adult CF subjects (subject mean = 179 days) through periods of clinical stability and 11 CF pulmonary exacerbations (CFPE). While microbiome profiles were personalized (permutational multivariate analysis of variance [PERMANOVA] r 2 = 0.79, P < 0.001), we observed significant intraindividual temporal variation that was highest during clinical stability (linear mixed-effects [LME] model, P = 0.002). This included periods where the microbiomes of different subjects became highly similar (UniFrac distance, <0.05). There was a linear increase in the microbiome alpha-diversity and in the log ratio of anaerobes to pathogens with time (n = 14 days) during the development of a CFPE (LME P = 0.0045 and P = 0.029, respectively). Collectively, comparing samples across disease states showed there was a reduction of these two measures during antibiotic treatment (LME P = 0.0096 and P = 0.014, respectively), but the stability data and CFPE data were not significantly different from each other. Metabolome alpha-diversity was higher during CFPE than during stability (LME P = 0.0085), but no consistent metabolite signatures of CFPE across subjects were identified. Virulence-associated metabolites from P. aeruginosa were temporally dynamic but were not associated with any disease state. One subject died during the collection period, enabling a detailed look at changes in the 194 days prior to death. This subject had over 90% Pseudomonas in the microbiome at the beginning of sampling, and that level gradually increased to over 99% prior to death. This study revealed that the CF microbiome and metabolome of some subjects are dynamic through time. Future work is needed to understand what drives these temporal dynamics and if reduction of anaerobes correlate to clinical response to CFPE therapy.IMPORTANCE Subjects with cystic fibrosis battle polymicrobial lung infections throughout their lifetime. Although antibiotic therapy is a principal treatment for CF lung disease, we have little understanding of how antibiotics affect the CF lung microbiome and metabolome and how much the community changes on daily timescales. By analyzing 594 longitudinal CF sputum samples from six adult subjects, we show that the sputum microbiome and metabolome are dynamic. Significant changes occur during times of stability and also through pulmonary exacerbations (CFPEs). Microbiome alpha-diversity increased as a CFPE developed and then decreased during treatment in a manner corresponding to the reduction in the log ratio of anaerobic bacteria to classic pathogens. Levels of metabolites from the pathogen P. aeruginosa were also highly variable through time and were negatively associated with anaerobes. The microbial dynamics observed in this study may have a significant impact on the outcome of antibiotic therapy for CFPEs and overall subject health

Multi-omics analyses of the ulcerative colitis gut microbiome link Bacteroides vulgatus proteases with disease severity.

Ulcerative colitis (UC) is driven by disruptions in host-microbiota homoeostasis, but current treatments exclusively target host inflammatory pathways. To understand how host-microbiota interactions become disrupted in UC, we collected and analysed six faecal- or serum-based omic datasets (metaproteomic, metabolomic, metagenomic, metapeptidomic and amplicon sequencing profiles of faecal samples and proteomic profiles of serum samples) from 40 UC patients at a single inflammatory bowel disease centre, as well as various clinical, endoscopic and histologic measures of disease activity. A validation cohort of 210 samples (73 UC, 117 Crohn's disease, 20 healthy controls) was collected and analysed separately and independently. Data integration across both cohorts showed that a subset of the clinically active UC patients had an overabundance of proteases that originated from the bacterium Bacteroides vulgatus. To test whether B. vulgatus proteases contribute to UC disease activity, we first profiled B. vulgatus proteases found in patients and bacterial cultures. Use of a broad-spectrum protease inhibitor improved B. vulgatus-induced barrier dysfunction in vitro, and prevented colitis in B. vulgatus monocolonized, IL10-deficient mice. Furthermore, transplantation of faeces from UC patients with a high abundance of B. vulgatus proteases into germfree mice induced colitis dependent on protease activity. These results, stemming from a multi-omics approach, improve understanding of functional microbiota alterations that drive UC and provide a resource for identifying other pathways that could be inhibited as a strategy to treat this disease

American Gut: an Open Platform for Citizen Science Microbiome Research.

Although much work has linked the human microbiome to specific phenotypes and lifestyle variables, data from different projects have been challenging to integrate and the extent of microbial and molecular diversity in human stool remains unknown. Using standardized protocols from the Earth Microbiome Project and sample contributions from over 10,000 citizen-scientists, together with an open research network, we compare human microbiome specimens primarily from the United States, United Kingdom, and Australia to one another and to environmental samples. Our results show an unexpected range of beta-diversity in human stool microbiomes compared to environmental samples; demonstrate the utility of procedures for removing the effects of overgrowth during room-temperature shipping for revealing phenotype correlations; uncover new molecules and kinds of molecular communities in the human stool metabolome; and examine emergent associations among the microbiome, metabolome, and the diversity of plants that are consumed (rather than relying on reductive categorical variables such as veganism, which have little or no explanatory power). We also demonstrate the utility of the living data resource and cross-cohort comparison to confirm existing associations between the microbiome and psychiatric illness and to reveal the extent of microbiome change within one individual during surgery, providing a paradigm for open microbiome research and education. IMPORTANCE We show that a citizen science, self-selected cohort shipping samples through the mail at room temperature recaptures many known microbiome results from clinically collected cohorts and reveals new ones. Of particular interest is integrating n = 1 study data with the population data, showing that the extent of microbiome change after events such as surgery can exceed differences between distinct environmental biomes, and the effect of diverse plants in the diet, which we confirm with untargeted metabolomics on hundreds of samples

American Gut:an Open Platform for Citizen Science Microbiome Research

Although much work has linked the human microbiome to specific phenotypes and lifestyle variables, data from different projects have been challenging to integrate and the extent of microbial and molecular diversity in human stool remains unknown. Using standardized protocols from the Earth Microbiome Project and sample contributions from over 10,000 citizen-scientists, together with an open research network, we compare human microbiome specimens primarily from the United States, United Kingdom, and Australia to one another and to environmental samples. Our results show an unexpected range of beta-diversity in human stool microbiomes compared to environmental samples; demonstrate the utility of procedures for removing the effects of overgrowth during room-temperature shipping for revealing phenotype correlations; uncover new molecules and kinds of molecular communities in the human stool metabolome; and examine emergent associations among the microbiome, metabolome, and the diversity of plants that are consumed (rather than relying on reductive categorical variables such as veganism, which have little or no explanatory power). We also demonstrate the utility of the living data resource and cross-cohort comparison to confirm existing associations between the microbiome and psychiatric illness and to reveal the extent of microbiome change within one individual during surgery, providing a paradigm for open microbiome research and education. IMPORTANCE We show that a citizen science, self-selected cohort shipping samples through the mail at room temperature recaptures many known microbiome results from clinically collected cohorts and reveals new ones. Of particular interest is integrating n = 1 study data with the population data, showing that the extent of microbiome change after events such as surgery can exceed differences between distinct environmental biomes, and the effect of diverse plants in the diet, which we confirm with untargeted metabolomics on hundreds of samples

Enhancing untargeted metabolomics using metadata-based source annotation

Human untargeted metabolomics studies annotate only ~10% of molecular features. We introduce reference-data-driven analysis to match metabolomics tandem mass spectrometry (MS/MS) data against metadata-annotated source data as a pseudo-MS/MS reference library. Applying this approach to food source data, we show that it increases MS/MS spectral usage 5.1-fold over conventional structural MS/MS library matches and allows empirical assessment of dietary patterns from untargeted data

movie_s1.mp4

Longitudinal samples from a large bowel resection. We place longitudinal samples collected prior to and following a large bowel resection in the context of samples from the AGP, the Earth Microbiome Project (https://www.ncbi.nlm.nih.gov/pubmed/29088705), intensive care unit patients (https://www.ncbi.nlm.nih.gov/pubmed/27602409), "extreme" diet samples from (https://www.ncbi.nlm.nih.gov/pubmed/24336217), and samples from the Hadza hunter-gatherers (https://www.ncbi.nlm.nih.gov/pubmed/28839072). Unweighted UniFrac was computed on this sample set, and principal coordinates were assessed. Using EMPeror (https://www.ncbi.nlm.nih.gov/pubmed/24280061), we then animate the plot by connect successive data points gut resection time series, while rotating the data frame. We first show the how the extent of change in the microbial community, and how the samples immediately following surgery resemble fecal samples from ICU patients. In the background of the animation, a black line connects a plant rhizosphere sample to a marine sediment sample, which have the same unweighted UniFrac distance (0.78) as the longitudinal sample immediately preceding and immediately following surgery

Full American Gut Project mapping file

The full American Gut Project mapping file, includes non-fecal samples