"Streptococcus anaerobius" Peptostreptococcus anaerobius is a species of bacteria belonging to the Peptostreptococcus genus of anaerobic, Gram-positive, non-spore forming bacteria.

The cells are small, spherical, and can occur in short chains, in pairs or individually.

[2] Peptostreptococcus are slow-growing bacteria sometimes resistance to antimicrobial drugs.

[3] P. anaerobius is intrinsically resistant to sodium polyethanol sulfonate (SPS), a component found in many types of blood culture media.

[4] Peptostreptococcus anaerobius is present as part of the microbiota of the lower reproductive tract of women and has been recovered from women with pelvic inflammatory disease and bacterial vaginosis.