A PCR-Based Method for Distinguishing between Two Common Beehive Bacteria, Paenibacillus larvae and Brevibacillus laterosporus.

and are two bacteria that are members of the family. Both are commonly found in beehives and have historically been difficult to distinguish from each other due to related genetic and phenotypic characteristics and a shared ecological niche. Here, we discuss the likely mischaracterization of three 16S rRNA sequences previously published as and provide the phylogenetic evidence that supported the GenBank reassignment of the sequences as We explore the issues that arise by using only 16S rRNA or other single-gene analyses to distinguish between these bacteria. We also present three sets of molecular markers, two sets that distinguish from and other closely related species within the genus and a third set that distinguishes from and other closely related species within the genus. These molecular markers provide a tool for proper identification of these oft-mistaken species. 16S rRNA gene sequencing in bacteria has long been held as the gold standard for typing bacteria and, for the most part, is an excellent method of taxonomically identifying different bacterial species. However, the high level of 16S rRNA sequence similarity of some published strains of and , as well as possible horizontal gene transfer events within their shared ecological niche, complicates the use of 16S rRNA sequence as an effective molecular marker for differentiating these two species. Additionally, shared characteristics of these bacteria limit the effectiveness of using traditional phenotypic identification assays, such as the catalase test. The results from this study provide PCR methods to quickly differentiate between these two genera and will be useful when studying , , and other disease-relevant bacteria commonly found in beehives.