Diversity And Spatio-temporal Analysis Of Symbiotic Bacteria In Bombus Lantschouensis

Bumblebees are important pollinators for agricultural and natural ecosystems. Symbionts in bumblebees endow their host multiple functions in the nutrition supply and colonization resistance against invasion of exotic microbes. Bombus lantschouensis is a native species, widely distributed in China and has important commercial value. Therefore, this article studied the diversity and spatio-temporally analysis of symbionts in B. lantschouensis gut, and we cultured and isolated some of these bacteria. The results showed:(1) Diversity of symbiotic bacteria in B. lantschouensisA16S rDNA clone library of gut bacteria was constructed to analyse the diversity of bacteria in B. lantschouensis gut, we got202sequences, divided them into16OTUs (operational taxonomic units). The phylogenetic analysis showed that the sequences clustered into6major lineages within the domain bacteria. Among them,45%and30%were respectively Gilliamella and Snodgrassella,10%were Bifidobacterium,5%were Fructobacillus,2%were Lactobacillus, and8%were mixture of uncommon bacteria types.(2) Spatio-temporal analysis of G. apicola and S. alvi in B. lantschouensisTotal genomic DNA was extracted from Egg, Larva, Pupa, and0,5,10,15,20days worker bees. The quantitative real-time PCR (qPCR) was used to explore the quantity variation of symbionts during the different developmental stages of B. lantschouensis. The qPCR result showed that G. apicola and5. alvi were detected in all development stages, the quantity of G. apicola and S. alvi in Egg, Larva and Pupa were very low, in5days significantly higher than those in other development stages, and then gradually reduced, stabilized after15days, the bacteria quantity in20days show no difference with15days. The two bacterial species were similar in the quantity variation patterns with decreasing after increasing, finally reach the steady state.(3) Culture of gut bacteria from B. lantschouensisNine different strains of bacteria from B. lantschouensis gut were identified by morphologic and16S rDNA gene analysis. They were grouped into Pseudomonas, Klebsiella, Enterobacter, Enterobacter, Bacillus, Proteus, Staphylococcus, Lactobacillus and Snodgrassella. These bacteria are common bacteria types isolated from honeybee intestinal. Among them, S. alvi strain C3is a dominant bacterium in B. lantschouensis, it is one of the two symbiotic bacteria our study focused. The phylogenetic tree showed that S. alvi strain C3from our results was clustered one clade with S. alvi isolated from other bumblebee species and distinct from S. alvi isolated from Apis cerana cerana Fabricius and Apis mellifera Linnaeus. The S. alvi strain C3we isolated laid a foundation for further functional research of S. alvi in B. lantschouensis.