Characterization of four novel members of genus Streptococcus from wild animals: description of Streptococcus handemini sp. nov., Streptococcus jiangjianxini sp. nov., Streptococcus tangpeifui sp. nov. and Streptococcus huangxiaojuni sp. nov.

Four novel strain pairs (ZJ93^T/ZJ100, ZJ151^T/ZJ99, ZJ1593^T/ZJ373 and H31^T/H49) were isolated from the respiratory tracts of marmots and the faeces of white-lipped deer. All eight isolates were facultatively anaerobic, oxidase- and catalase-negative, non-spore-forming, non-motile and Gram-stain-positive cocci in short and long chains. Analyses of the 16S rRNA gene and genome sequences revealed that the eight strains represent four novel species of the genus Streptococcus. The 16S rRNA gene sequence analysis showed that strain ZJ93^T had the highest similarity to Streptococcus marmotae HTS5^T (98.23%), ZJ151^T to Streptococcus halotolerans HTS9^T (98.18%), ZJ1593^T to Streptococcus criceti HS-6^T (96.77%) and H31^T to Streptococcus pantholopis TA 26^T (98.25%). The values of digital DNA-DNA hybridization between the four novel species and their phylogenetically related type strains of the genus Streptococcus were far below 70%, but higher than 70% within each pair of novel strains (ZJ93^T/ZJ100, ZJ151^T/ZJ99, ZJ1593^T/ZJ373 and H31^T/H49). The DNA G+C contents of ZJ93^T, ZJ151^T, ZJ1593^T and H31^T were 41.0, 39.0, 41.5 and 41.5 mol%, respectively. The main cellular fatty acid of all eight strains was C_{16 : 0}. Based on the results from the aforementioned analyses, the eight novel strains were classified as representing four novel species of genus Streptococcus, for which the names Streptococcus handemini sp. nov. [type strain ZJ93^T (=GDMCC 1.3112^T=JCM 35325^T)], Streptococcus jiangjianxini sp. nov. [type strain ZJ151^T (=GDMCC 1.3116^T=JCM 35326^T)], Streptococcus tangpeifui sp. nov. [type strain ZJ1593^T (=GDMCC 1.3115^T=JCM 35327^T)] and Streptococcus huangxiaojuni sp. nov. [type strain H31^T (=GDMCC 1.4758^T=JCM 37397^T)] are proposed, respectively.