Submitted to: Infection, Genetics and Evolution
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/26/2008
Publication Date: 11/5/2008
Citation: Johny, S., Larson, T.M., Solter, L.F., Edwards, K.A., Whitman, D.W. 2008. Phylogenetic Characterization of Encephalitozoon Romaleae (Microsporidia) from a Grasshopper Host: Relationship to Encephalitozoon spp. Infecting Humans. Infection, Genetics and Evolution. 9:189-195. Interpretive Summary: A new species of parasite was found infecting eastern lubber grasshoppers. In order to determine the relationship between this parasite and other related species, we cloned and sequenced several genes from the new parasite. The sequences were compared to other related species and placing the new species within the Encephalitozoon clade and clustered with the species E. hellum. The new species was named E. romaleae.
Technical Abstract: Encephalitozoon species are the most common microsporidian pathogens of humans and domesticated animals. We recently discovered a new microsporidium, Encephalitozoon romaleae, infecting the eastern lubber grasshopper Romalea microptera. To understand its evolutionary relationships, we compared partial gene sequences of a- and b-tubulin and methionine aminopeptidase 2 enzyme from this and related species. We also analyzed the rRNA internal transcribed spacer. Based on tubulin and MetAP-2 gene phylogenetic analysis, E. romaleae clustered with the Encephalitzoon group with strong bootstrap support (>99%). Within the Encephalitozoon clade, E. romaleae clustered with Encephalitozoon hellem for both the b-tubulin and MetAP-2 phylogenies based on ML tree. The a-tubulin based ML tree, however, placed the new microsporidium closer to Encephalitozoon cuniculi. The rRNA internal transcribed spacer region of E. romaleae has 91% homology with E. hellem.