Bacteriophages and the honeybee gut microbiome impacts on immunity and disease resistance

Project summary

Honeybees (Apis mellifera) are highly effective pollinators of flowering plants, including many crops. As such, they have a high economic and ecological impact. However, managed honeybee colonies suffer from various health issues including pathogen infection leading to weakened immune responses, making colonies more susceptible to other stressors such as pesticides and poor nutrition. The honeybee gut microbiota is believed to play a crucial role in achieving and maintaining health by aiding in digestion, nutrient absorption and training of the immune system. Furthermore, the microbiota is also believed to be important for resilience against viral, bacterial and parasite infections and subsequent diseases.

This process and especially the role of specific bacteria and their viruses (called bacteriophages, or phages) is poorly understood. In the microBEEome project we will: 1) Isolate and characterize bacteriophages using a unique collection of European honeybee gut bacteria; 2) Inoculate microbiota-free (axenic) worker bees with several combinations of bacteria and their bacteriophages to assess the natural evolution of the gut microbiome and its impact on natural development of its host; 3) Assess the effects of different microbiota on honeybee immune development, and 4) assess the resilience of honeybees inoculated with different combinations of gut microbiota towards in vivo challenges with natural pathogens such as Nosema, a unicellular parasite from the group of microsporidia, and Deformed Wing Virus (DWV), arguably the most prevalent and detrimental honeybee pathogen. This study will provide valuable insights into the role of individual bacteria or bacterial communities (with or without bacteriophages) in honeybee health, immune response and resilience, and may lead to the development of probiotics or other microbiome-based interventions to promote honeybee health.