- The Canada goose (Branta canadensis) monogastric gut is proposed to contain aerobic spore-forming bacteria that produce non-toxin substances that may promote anti-inflammatory immune responses. It is hypothesized that the aerobic bacteria found in samples of Canada goose microflora could have probiotic effects in other avian species or used for commercial or ecosystems analyses. To investigate this, two Gram-variable, spore forming, rod-shaped and chloroform tolerant aerobic bacteria strains A4 and A15 were isolated from fecal samples of resident Canada geese (Branta canadensis). Using a 16S rRNA gene sequences analysis it was determined that both novel strains were 94% similar to other Sporosarcina species rRNA genes and both had their own unique 16S rRNA sequence. Both A4 and A15 were found to contain urease genes, GerA spore germination protein genes, and a fibronectin binding protein. The digital DNA–DNA hybridization (dDDH) of both strains to similar genomes and between each other was <28%, below the 70% cut-off for species definition. In addition, the average nucleotide identity (ANI) and average amino acid identity (AAI) values of both strains were <82% for A4 and <88% for A15, also below the cut-off values for species definition. Phenotypic characteristics were tested, including phenotypic assays testing for 177 different carbon sources and assays testing for pH effects on growth. It was concluded that A4 and A15 represent two novel strains of the Sporosarcina genus, Sporosarcina cascadiensis (A4) and Sporosarcina obsidiansis (A15).
Key Words: Microbiome, Spore-forming bacteria, Probiotic, Average Nucleotide Identity