Lactobacillus metriopterae sp. nov., a novel lactic acid bacterium isolated from the gut of grasshopper Metrioptera engelhardti.

A strain (Hime 5-1) of lactic acid bacterium was isolated from the gut of the grasshopper Metrioptera engelhardti from a mountainous area of Nagano Prefecture, Japan. Strain Hime 5-1 had a low 16S rRNA gene sequence similarity to known lactic acid bacteria, with the closest recognized relatives being Lactobacillus tucceti (96.7 %), Lactobacillus furfuricola (96.5 %), Lactobacillus versmoldensis (96.3 %) and Lactobacillus nodensis (96.1 %). Comparative analyses of the rpoA and pheS gene sequences indicated that Hime 5-1 is not closely related to other Lactobacillus species. Strain Hime 5-1 is a Gram-stain-positive, catalase-negative and homofermentative bacterium with yellowish colonies, which contrasts with the whitish colonies of its closest recognized relatives. Based on phenotypic and genotypic properties, we conclude that the isolated bacterium represents a novel species of the genus Lactobacillus, for which the name Lactobacillus metriopterae sp. nov. is proposed. The type strain is Hime 5-1 (=JCM 31635=DSM 103730). 16S rRNA gene based high-throughput sequencing revealed that L. metriopterae is the dominant microbiota in the gut of Metrioptera engelhardti.