In this study, a novel bacterial strain, IMAU11622 T , was isolated from the milk of yaks in Yunnan Province, China. This strain was characterized as a Gram-positive, catalase-negative, α -haemolytic, coccus-shaped bacterium belonging to the genus Streptococcus ( S .). The strain IMAU11622 T belongs to the mitis-suis clade, the pneumoniae subclade, of the genus Streptococcus . Phylogenetic analysis based on 16S rRNA gene sequence analysis revealed that the strain IMAU11622 T shared high similarity with S. mitis ATCC 49456 T and S. thalassemiae Marseille Q2617 T (99.7%), S. pseudopneumoniae CCUG 49455 T (99.5%), S. pneumoniae ATCC 33400 T (99.2%), S. oralis subsp. oralis ATCC 35037 T and S. oralis subsp. dentisani Str. 7747 T (99.1%) and S. infantis ATCC 700779 T (99.0%). Phylogenetic analysis of 7 housekeeping gene ( rpoB , gyrB , ppaC , sodA , tuf , pflA and guaA ) sequences and a phylogenetic tree based on 158 core genes further differentiated the strain IMAU11622 T , which was distinct from the closely related strains. The highest average nucleotide identity and digital DNA–DNA hybridization values for strain IMAU11622 T were 94.6 and 55.6%, respectively, in comparison with S. mitis ATCC 49456 T . The draft genome size of strain IMAU11622 T was 1,973,043 bp, and the DNA G+C content of the type strain was 40.0%. The major cellular fatty acids were C 16 : 0 , summed feature 3 (containing C 16 : 1 ω 7c/or C 16 : 1 ω 6c), summed feature 8 (containing C 18 : 1 ω 7c and C 18 : 1 ω 6c) and C 14 : 0 . The strain IMAU11622 T exhibited growth at a temperature ranging 25–45 °C (with an optimum growth temperature of 37 °C), a pH range of 5.0–8.0 (with an optimum growth pH of 7.0) and tolerance up to 2% NaCl. Based on polyphasic taxonomic characterization, the strain IMAU11622 T is a novel species within the genus Streptococcus , for which the name Streptococcus bovismuti sp. nov. is proposed, with the type strain IMAU11622 T (=JCM 37064 T =CGMCC 1.64733 T =GDMCC 1.4462 T ).
Wei et al. (2026) studied this question.