Numerical taxonomy of Streptococcus

Abstract

A numerical taxonomic study of strains of Streptococcus, together with representatives of allied genera, showed 28 reasonably distinct phenons. The major areas, with their phenons, were: enterococcal species group (S.faecalis, S.faecium, 'S.avium' and a proposed new species 'S.gallinarum'); paraviridans species group (S.bovis, S.equinus, S.salivarius, 'S.casseliflavus', S.mutans, S.raffinolactis and an unidentified Oral Group I); lactic species group (S.lactis including S.cremoris); thermophilic species group (S.thermophilus); viridans species group (S.mitis, S.sanguis, a proposed new species 'S.oralis' and 'S.milleri'); pyogenic species group (S.agalactiae, S.pyogenes, S.equi, 'S.equisimilis' including 'S.zooepidemicus', and a cluster of Lancefield Group B strains of human origin); parapyogenic species group (S.uberis, 'S.dysgalactiae', and a cluster of strains of Lancefield Groups R, S and T). Species of Aerococcus, Gemella, Leuconostoc and Pediococcus are very closely related to the streptococci.