Project description:This study investigated how gut-derived bacterial supplementation influences the honey bee gut microbiota, metabolism, and proteome under three experimental settings: (i) controlled laboratory conditions (C versus B), (ii) semi-controlled laboratory conditions with or without social interaction with older nestmates (COB versus BOB), and (iii) field conditions (CON versus TRT). A bacterial mixture containing Lactobacillus helsingborgensis, L. apis, Bifidobacterium choladohabitans, and B. polysaccharolyticum was administered. Gut samples were collected after 10 days and analyzed for microbiome (16s rRNA sequencing), metabolome (1H NMR), and proteome profiles (LFQ-proteomics, laboratory experiment only). Proteomic profiling revealed distinct group-specific host responses. Control bees (C and COB) upregulated ribosomal proteins linked to protein synthesis and cellular stress. Supplemented bees in group B showed strong induction of major royal jelly proteins (MRJP1 and MRJP5), associated with neural modulation and colony behavior. In BOB, elevated expression of mitochondrial enzymes suggested improved energy metabolism in the presence of social context. Bacterial supplementation induces reproducible, condition-dependent changes across microbiota, metabolic, and proteomic layers. These findings provide mechanistic insight into how microbial interventions reshape gut function and support honey bee health under realistic environmental conditions.
Project description:Understanding the biological mechanisms underlying extreme lifespan variation within species remains a fundamental challenge in aging research. Here, we investigated the role of gut microbiota and age in honey bee (Apis mellifera) queens combining metagenomics and transcriptomics. Analysis of 40 queen hindguts revealed that Commensalibacter melissae (Alpha 2.1) relative abundance was significantly higher in young queens compared to old queens. Using queens with the highest and lowest C. melissae relative abundance, RNA sequencing identified 1,451 differentially expressed genes associated with C. melissae abundance, twice the number associated with age alone (719 genes). Queens with high C. melissae abundance showed distinct transcriptional profiles related to stress response, protein homeostasis, and longevity-regulating pathways, particularly genes involved in oxidative stress response and cellular maintenance. Our analysis revealed complex relationships between age, C. melissae abundance, and gene expression patterns, suggesting that multiple interacting factors contribute to queen quality. These findings contribute to our understanding of host-microbe interactions in honey bee queens and highlight the intricate relationship between gut microbiota composition and host physiology in honey bees.