Abstract
The composition of the gut microbiota in animals can be influenced by a variety of intrinsic and extrinsic factors in the host, such as diet, physiological state, and genetics. This study aimed to compare the structural composition of the gut microbiota of Apis mellifera bees from two distinct Brazilian biomes, the Atlantic Forest and the Caatinga, using high throughput 16 S rRNA sequencing. We identified a core microbiota composed of seven genera present in all samples: Lactobacillus, Commensalibacter, Rhizobiaceae, Snodgrassella, Gilliamella, Orbaceae and Bifidobacterium. These taxa accounted for 63% of all bacterial genera in the dataset. Interestingly, we observed a significantly differential abundance of the genus Apibacter between bees from the two biomes, with a marked increase in bees from Atlantic Forest. However, the overall variance in the gut structural composition attributable to landscape type, while significant, was relatively low. Notably, none of the members of the core microbiota were differently abundant between the biomes. Understanding the magnitude of landscape-associated effects on the microbiota of bees in different biomes is crucial for the accurate assessment of the impact of anthropogenic factors. These findings provide important insights into the resilience and adaptability of the honey bee gut microbiome across contrasting environments, contributing to the development of conservation and sustainable management strategies for these essential pollinators.