Peptostreptococcus

Abstract

The genus Peptostreptococcus, currently including two species of gram-positive, obligately anaerobic cocci, Peptostreptococcus anaerobius and Peptostreptococcus stomatis, belongs to the family Peptostreptococcaceae in the phylum Firmicutes. The genus was described in 1936 by Kluyver and van Niel, 1 P. anaerobius being chosen as the type species of the genus, and this was confirmed in the Approval Lists of Bacterial Names in 1980.2 At that time, the genus was still composed of a widely diverse group of gram-positive coccal organisms, including four species: P. anaerobius, Peptostreptococcus micros, Peptostreptococcus parvulus, and Peptostreptococcus productus.2 Since then, the latter two species have been transferred to other genera twice, currently locating in novel genera as Atopobium parvulum (formerly Streptococcus parvulus)3 and Blautia producta (formerly Ruminococcus productus), 4 respectively. In contrast, the former Peptococcus species, except Peptococcus niger, were transferred to the genus Peptostreptococcus, 5 and a considerable number of new species have been recovered and described as members of Peptostreptococcus.5–7