Philipp Engel, Waldan Kwong, and Nancy Moran's paper "Frischella perrara gen. nov., sp. nov., a gammaproteobacterium isolated from the gut of the honey bee, Apis mellifera" is in press at the International Journal of Systematic and Evolutionary Microbiology (IJSEM).
The gut of the Western honey bee, Apis mellifera, is colonized by a characteristic set of bacteria. Two distinct Gammaproteobacteria are consistent members of this unique microbial community, and one has recently been described as a nov. gen., nov. sp. with the name Gilliamella apicola. Here, we present isolation and characterization of PEB0191T, a strain belonging to the second gammaproteobacterial species present in the honey bee gut microbiota, formerly referred to as Gammaproteobacterium-2. Cells of strain PEB0191T are mesophilic with an average length of around 2 μm, and optimal growth was achieved under anaerobic conditions. Growth was not obtained under aerobic conditions and was reduced in a microaerophilic environment. Based on sequence analysis, strain PEB0191T belongs to the Orbaceae, and its closest relatives with around 95% sequence similarity are species of the genus Orbus and the genus Gilliamella. Phylogenetic analyses suggest, however, that PEB0191T is more closely related to the genus Orbus than to the genus Gilliamella. In accordance with its evolutionary relationship, further similarities between strain PEB0191T and other members of the Orbaceae were revealed based on the respiratory quinone type (ubiquinone-8), the fatty acid profile, and the DNA G+C content. Interestingly, like strains of the genus Gilliamella, PEB0191T exhibited a high level of resistance against oxytetracycline. The similar levels of sequence divergence from the genera Gilliamella and Orbus and its uncertain phylogenetic position within the family Orbaceae indicate that strain PEB0191T represents a novel species of a novel genus with the proposed name Frischella perrara gen. nov., sp. nov.. The type strain is PEB0191T (=NCIMB 14821T=ATCC BAA-2450T).