Microbial communities associated with honey bees in Brazil and in the United States

Authors: SCOARIS, DENISE - Federal University Of Minas Gerais; HUGHES, FREDERIC - Federal University Of Minas Gerais; SILVEIRA, MILTON - Federal University Of Minas Gerais; Evans, Jay; PETTIS, JEFFERY - North Carolina State University; BASTOS, ESTHER - Federal University Of Minas Gerais; ROSA, CARLOS - Federal University Of Minas Gerais

Submitted to: Brazilian Journal of Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2021
Publication Date: 7/15/2021
Citation: Scoaris, D.O., Hughes, F.M., Silveira, M.A., Evans, J.D., Pettis, J., Bastos, E.M., Rosa, C.A. 2021. Microbial communities associated with honey bees in Brazil and in the United States. Brazilian Journal of Microbiology. 52:2097-2115. https://doi.org/10.1007/s42770-021-00539-7.
DOI: https://doi.org/10.1007/s42770-021-00539-7

Interpretive Summary: Honey bee colonies contain beneficial and harmful microbes. A combination of laboratory culturing of microbes and genetic analyses can characterize the many microbes found in healthy and failing colonies. To do so, it is important to develop baseline data from healthy colonies. This study compared fungi and bacteria from colonies in Brazil and the US. There were surprisingly large differences between the two populations, suggesting a diversity of microbes, most of which do not cause disease. Microbes are important for bee health and these efforts are needed to ensure continued availability of honey bees as pollinators. Specifically, the results can help guide efforts to develop probiotic treatments for colonies and to understand the origins of opportunistic pathogens.

Technical Abstract: Honey bee colony losses worldwide call for a more in-depth understanding of the pathogenic and mutualistic components of the honey bee microbiota and their relation with the environment. In this descriptive study, we characterized the yeast and bacterial communities that arise from six substrates associated with honey bees: corbicular pollen, beebread, hive debris, intestinal contents, body surface of nurses and foragers bees, from two different landscapes, Minas Gerais, in the southeast of Brazil and Maryland, in the United States. The sampling of five hives in Brazil and four in the US yielded 216 yeast and 283 bacterial isolates. Whereas the yeast community, accounted for 45 species from 28 genera, was dominated in Brazil by Aureobasidium pullulans and Candida orthopsilosis, the major yeast recovered from US was Debaryomyces hansenii. The bacterial community was more diverse, encompassing 60 species distributed across 28 genera. Overall, most isolates belonged to Firmicutes, genus Bacillus and, among LAB, species from Lactobacillus were the most prevalent in both environments. The microbial beta diversity was assessed by partitioning models. Cluster analyses of the structure of the microbial communities showed two distinguished microbial groups between Brazil and the United States. While in the US, changes in microbiota largely reflected species replacement through turnover, which accounted for 91.3% (i.e. 0.716 out of 0.784) of the total beta diversity, in Brazil we found a more pronounced effect of nestedness (i.e., 27.90%; 0.219 out of 0.785) for microbiota change. The relative abundance of yeasts and bacterial groups also showed the dissimilarity of the microbial communities between both environments, evidenced by the low rate of shared species (six yeasts and twelve bacteria). These results provide a comprehensive view of microorganisms associated with A. mellifera in two distinct environments, highlighting the importance of the environment in the establishment of the microbiota associated with honey bees.