Significant compositional and functional variation reveals the patterns of gut microbiota evolution among the widespread Asian honeybee populations

Abstract

The gut microbiome is a crucial element that facilitates a host’s adaptation to a changing environment. Compared to the western honeybee Apis mellifera, the Asian honeybee, Apis cerana populations across its natural range remain mostly semi-feral and are less affected by bee management, which provides a good system to investigate how gut microbiota evolve under environmental heterogeneity on large geographic scales. We compared and analyzed the gut microbiomes of 99 Asian honeybees, from genetically diverged populations covering 13 provinces across China. Bacterial composition varied significantly across populations at phylotype, sequence-discrete population (SDP), and strain levels, but with extensive overlaps, indicating that the diversity of microbial community among A. cerana populations is driven by nestedness. Pollen diets were significantly correlated with both the composition and function of the gut microbiome. Core bacteria, Gilliamella and Lactobacillus Firm-5, showed antagonistic turnovers and contributed to the enrichment in carbohydrate transport and metabolism. By feeding and inoculation bioassays, we confirmed that the variations in pollen polysaccharide composition contributed to the trade-off of these core bacteria. Progressive change, i.e., nestedness, is the foundation of gut microbiome evolution among the Asian honeybee. Such a transition during the co-diversification of gut microbiomes is affected by environmental factors, diets in general, and pollen polysaccharides in particular.

Reactive oxygen species are regulated by immune deficiency and Toll pathways in determining the host specificity of honeybee gut bacteria

“…In addition to host regulation, the successful colonization of honeybee core bacteria is clearly influenced by multifaceted factors. For example, Gilliamella also relies on its interaction with Snodgrassella in vivo ( 15 , 59 ), as well as variations in pollen diet ( 60 ) and other nutrients obtained by the host ( 14 ). How these parameters interact remains unanswered.…”

“…The genome of B19101 was sequenced with the Illumina NovaSeq platform. Genome assemblies and annotation of B19101 followed pipelines in Su et al ( 60 ). The phylogenetic tree including B19101 and W8127 was built with RAxML ( 63 ).…”

Carbon Emission and Biodiversity of Arctic Soil Microbial Communities of the Novaya Zemlya and Franz Josef Land Archipelagos

“…Other gut microbiota-associated proteobacterial genera detected in Novaya Zemlya samples included Klebsiella , Morganella , Serratia , and Snodgrassella. Interestingly, ASVs, belonging to Gilliamella genus in which valid and cultivated representatives are isolated exclusively from bee gut [ 46 ], were found in significant amounts (1.2% on average). ASVs from the Rhizobiaceae family have also been associated with the intestines of bees, and additional analysis has shown a high degree of similarity with the Bartonella apihabitans strain isolated from the bee gut.…”

Environment or genetic isolation? An atypical intestinal microbiota in the Maltese honey bee Apis mellifera spp. ruttneri

“…In addition, Powell et al (2016) showed how lineages of gut bacteria often include many closely related strains, not distinguishable at species level but highly specialized and restricted to a single host species or subspecies. Recently, Su et al (2022) studied the impact of both host genetics and diet on the gut microbial populations of different Apis ceranae subspecies. The results showed extensive overlapping of the gut microbial strains among different subspecies and suggested an effect of the floral diet in maintaining specialized bacterial traits.…”