Characterisation of the gut bacteriome of hill and plain race of Indian honey bee <i>Apis cerana</i> fabricius

Microbial communities are virtually present in every site of the body of the animals, but the ones associated with the gastrointestinal tract are home to a vast majority of microorganisms and are of importance due to their diverse impacts on animal health. The guts of the honey bees also consist of a distinctive microbiome and traditionally culturing technique was used for the exploration of their gut bacteriome. However, this did not give us a complete picture of the bacterial community. Recently, a more complete and precise picture of the potential bacteria can be explored using next-generation sequencing. The honey bee gut bacteriome is an essential aspect of bee health and this study is aimed at the microbiome of the bee gut by targeting the V1-V9 hyper variable region of the 16S rRNA gene with Nanopore sequencing using adult worker bees was performed from the plain and hill regions of Coimbatore to understand the bacteriome variations. A total of 3, 88,947 reads were obtained revealing five phyla and the gut of the bees was found to be dominated by the Proteobacteria. In addition to the metagenomics approach, the traditional method of isolating bacterial species using the culturing techniques was also done and a BLAST search was performed for the identification of the cultural isolates using the universal bacterial primers. The number of unique OTUs for hill and plain races were 30 and 9, respectively, and 9 OTUs were common to both the races. In hill race, Actinobacteria was unique and in plain race, Bacteriodota abundance was more. Bacteriome profile variation was also observed in plain and hill honey bee races mostly at the species and genus level.