Emended descriptions and recognition of Streptococcus constellatus, Streptococcus intermedius, and Streptococcus anginosus as distinct species.

Strains currently classified as Streptococcus anginosus include strains previously identified as Streptococcus constellatus (Prevot 1924) Holdeman and Moore 1974, Streptococcus intermedius (Prevot 1925), and "Streptococcus milleri" (Guthof 1956) because these specific epithets were argued to be later synonyms of Streptococcus anginosus (Andrewes and Horder 1906) Smith and Sherman 1938 by Coykendall et al. (Int. J. Syst. Bacteriol. 37:222-228, 1987). However, recent data from DNA-DNA hybridization experiments, whole-cell-derived polypeptide patterns determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and data from phenotypic testing have demonstrated that Streptococcus anginosus strains represent three readily identifiable taxa to which the previously assigned type strains of Streptococcus constellatus (strain NCDO 2226 [= ATCC 27823], Streptococcus intermedius (strain NCDO 2227 [= ATCC 27335], and Streptococcus anginosus (strain NCTC 10713 [= ATCC 33397] have been shown to belong. Therefore, we propose recognition of Streptococcus constellatus (emend.) (type strain NCDO 2226 [= ATCC 27823]), Streptococcus intermedius (emend.) (type strain NCDO 2227 [= ATCC 27335]), and Streptococcus anginosus (emend.) (type strain NCTC 10713 [= ATCC 33397]) as distinct species and propose an emended description of each of these taxa.