Biology subjects

Kesnerova, L.

Publications and source records attributed to Kesnerova, L..

3 recordsLinked to original sources

bioRxiv2023

Fecal transplant allows transmission of the gut microbiota in honey bees

The gut of honey bees is colonized by symbiotic bacteria during the first days of adult life, once bees have emerged from their wax cells. Within five days, the gut microbiota becomes remarkably stable and consistent across individual bees. Yet, the modes of acquisition and transmission of the gut microbiota are to be confirmed. Few studies suggested bees could be colonized via contact with fecal matter in the hive and via social interactions. However, the composition of the fecal microbiota is still unknown. It is particularly unclear whether all bacterial species can be found viable in the feces and can therefore be transmitted to newborn nestmates. Using 16s rRNA gene amplicon sequencing we revealed that the composition of the honey bee fecal microbiota is strikingly similar to the microbiota of entire guts. We found that fecal transplantation resulted in gut microbial communities largely similar to those obtained from feeding gut homogenates. Our study shows that fecal sampling and transplantation are viable tools for the longitudinal analysis of bacterial community composition and host-microbe interactions. Our results also imply that contact of young bees with fecal matter in the hive is a plausible route for the acquisition of the core gut microbiota.

microbiology↗

bioRxiv2019

Gut microbiota structure differs between honey bees in winter and summer

Adult honey bees harbor a specialized gut microbiota of relatively low complexity. While seasonal differences in community composition have been reported, previous studies have focused on compositional changes rather than differences in absolute bacterial loads. Moreover, little is known about the gut microbiota of winter bees, which live much longer than bees during the foraging season, and which are critical for colony survival. We quantified seven core members of the bee gut microbiota in a single colony over two years and characterized the community composition in 14 colonies during summer and winter. Our data shows that total bacterial loads substantially differ between foragers, nurses, and winter bees. Long-lived winter bees had the highest bacterial loads and the lowest community -diversity, with a characteristic shift towards high levels of Bartonella and Commensalibacter, and a reduction of opportunistic colonizers. Using gnotobiotic bee experiments, we show that diet is a major contributor to the observed differences in bacterial loads. Overall, our study reveals that the gut microbiota of winter bees is remarkably different from foragers and nurses. Considering the importance of winter bees for colony survival, future work should focus on the role of the gut microbiota in winter bee health and disease.

microbiology↗

bioRxiv2017

Disentangling metabolic functions of bacteria in the honey bee gut

It is presently unclear how much individual community members contribute to the overall metabolic output of a gut microbiota. To address this question, we used the honey bee, which harbors a relatively simple and remarkably conserved gut microbiota with striking parallels to the mammalian system and importance for bee health. Using untargeted metabolomics, we profiled metabolic changes in gnotobiotic bees that were colonized with the complete microbiota reconstituted from cultured strains. We then determined the contribution of individual community members in mono-colonized bees, and recapitulated our findings using in vitro cultures. Our results show that the honey bee gut microbiota utilizes a wide range of pollen-derived substrates including flavonoids and outer pollen wall components, suggesting a key role for degradation of recalcitrant secondary plant metabolites and pollen digestion. In turn, multiple species were responsible for the accumulation of organic acids and polyphenol degradation products, and a specific gut symbiont, Bifidobacterium asteroides, stimulated the production of host hormones known to impact bee development. While we found evidence for cross-feeding interactions, [~]80% of the identified metabolic changes were also observed in mono-colonized bees with Lactobacilli being responsible for the largest share of the metabolic output. These results suggest that bacteria in the honey bee gut colonize largely independent metabolic niches, which may be a general characteristic of gut microbiomes. Our study reveals diverse metabolic functions of gut bacteria that are likely to contribute to bee health, and provide fundamental insights into how metabolic functions are partitioned within gut communities.\n\nAuthor summaryHoney bees are important pollinators that harbor a simple gut microbiota with striking parallels to the mammalian system. This makes them relevant models to study gut microbiota functions and its impact on host health. We applied untargeted metabolomics to characterize metabolic changes induced by the gut microbiota, and to characterize contributions of the major community members. We find that the gut microbiota digests recalcitrant substrates derived from the bees pollen-diet. Most metabolic changes could be explained by the activity of individual community members suggesting substrate specificity and independent metabolic niches. Our study provides novel insights into the functional understanding of the bee gut microbiota and provides a framework for applying untargeted metabolomics to disentangle metabolic functions of gut bacteria.

microbiology↗