5. Conclusions and outlook
We have described key methods for studying symbiotic microorganisms in honey bee guts. Non-culture-based approaches in general, and NGS sequencing in particular, have greatly improved our capabilities when it comes to identifying the microbial communities associated with honey bees. FISH microscopy provides a means to visually examine the microenvironments where particular microbes occur. Culturing methods are also important, allowing researchers to isolate particular bacteria of interest for further study or gene identification, and enabling the assignment of particular functions to particular gut community members. The culture conditions required for bacterial species found in the honey bee gut, as described here, clearly show that these gut symbionts tend to require low oxygen conditions, as is the case for many microbes isolated from the intestines of mammals, but not always true for insect gut symbionts. Also, the bacterial symbionts in the digestive tracts of honey bees require fairly high culturing temperatures, but temperatures consistent with honey bee colonies. The techniques described in this chapter focus on bacterial communities, but can easily be adapted for other microbial groups, for the study of pathogens, or to elucidate interactions between potentially beneficial gut microorganisms and pathogens. In addition, many of these methods can readily be used to study the gut microbiota of other bee species, allowing for comparative studies across hosts. We hope the methods we describe will help others advance the state of knowledge regarding bee gut symbionts, an intriguing area of research.