Gut microbiota structure differs between honey bees in winter and summer

Lucie Kešnerová; Olivier Emery; Michaël Troilo; Joanito Liberti; Berra Erkosar; Philipp Engel

Notably, qPCR is a targeted approach, i.e. one can only quantify specific community 500 members for which corresponding primers have been designed, or assess the total amount 501 of bacteria using universal primers. Therefore, a combined approach of qPCR (or any other 502 quantitative method, e.g. flow cytometry) and relative composition analysis (such 16S rRNA 503 gene sequencing or shotgun metagenomics) is preferred, as it provides information about 504 the quantity and directionality of changes in a microbial community. The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/703512 doi: bioRxiv preprint nurses, and winter bees (Fig. 3A-C) . Strikingly, our experimental colonization of microbiota-512 depleted bees with a defined bacterial community showed that pollen in the diet 513 substantially increases gut weight and bacterial loads to levels comparable to those in 514 winter bees. In contrast, bacterial levels in bees fed on sugar water only were more similar 515 to those of foragers (Fig. 3F-H) . Therefore, we conclude that diet is an important factor that 516 can explain many of the differences observed between worker bee types. Seasonal changes 517 in gut microbiota composition in wild rodent populations [52] and humans [53, 54] have 518 also been found to coincide with dietary shifts, which is in agreement with the general 519 notion that dietary preferences is the main driver of community differences across a wide 520 range of animals [55] [56] [57] .