Adlercreutzia wanghongyangiae sp. nov., and Adlercreutzia shanghongiae sp. nov., two new members of the genus Adlercreutzia isolated from plateau pika (Ochotona curzoniae).

Abstract

Four anaerobic, Gram-stain-positive, non-motile, non-sporulating rod-shaped bacterial strains (R7^T, R21, R22 and R25^T) were isolated from the intestinal contents of plateau pika (Ochotona curzoniae) collected from the Qinghai-Tibet Plateau, PR China. The four isolates grew at between 25 and 42 °C (optimally at 35-37 °C), and with 0.3-3.3% NaCl (w/v) [optimum, 1.3% (w/v)]. Adding l-arginine to the medium could promote their growth. Strains R7^T and R21 were most closely related to Adlercreutzia caecimuris B7^T (97.48% 16S rRNA gene sequence similarity). Strains R25^T and R22 were most closely related to Adlercreutzia equolifaciens DSM 19450^T (98.25% 16S rRNA gene sequence similarity). The genome sequences of R7^T and R25^T were 2.89 and 2.90 Mb in size with 63.6 and 62.8 mol% DNA G+C contents, respectively. Phylogenetic analysis based on 16S rRNA gene sequences and core genes revealed that R7^T and R21 were most closely related to A. caecimuris B7^T and Adlercreutzia mucosicola DSM 19490^T, whereas R25^T and R22 were most closely related to A. equolifaciens DSM 19450^T and Adlercreutzia rubneri ResAG-91^T. R7^T, R25^T and the closely related species had average nucleotide identity (ANI) values of 81.9-83.2% as well as digital DNA-DNA hybridisation (dDDH) values between 27.3 and 27.9%, which clearly indicated that they represent two novel species within the genus Adlercreutzia. For R7^T and R25^T, meso-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan, and the whole cell sugars included galactose, glucose and ribose. On the basis of these results, we propose that strains R7^T and R25^T represent two novel species of the genus Adlercreutzia, namely Adlercreutzia wanghongyangiae sp. nov. and Adlercreutzia shanghongiae sp. nov., respectively. The type strains are R7^T (=GDMCC 1.4459^T=KCTC 25860^T) and R25^T (=GDMCC 1.4458^T=KCTC 25861^T).