Streptococcus massiliensis sp. nov., isolated from a patient blood culture.

An unidentified strain of the viridans group of streptococci was isolated from a human blood sample. It was distinguished from all other recognized species of the Streptococcus sanguinis group by several biochemical characteristics. Phylogenetic analysis based on 16S rRNA gene sequence comparisons clustered this strain with Streptococcus ferus (mutans group) but phylogenetic analysis based on rpoB and sodA gene sequence comparisons included it in the S. sanguinis group. The isolate showed 95.4 and 95.2 % 16S rRNA gene sequence similarity to S. ferus and S. sanguinis, respectively, confirming it as belonging to a novel taxon, for which the name Streptococcus massiliensis sp. nov. is proposed. The type strain is 4401825T (=CIP 108498T=CCUG 49690T).