SGM Journals
Research Article

Transfer of Peptococcus indolicus, Peptococcus asaccharolyticus, Peptococcus prevotii, and Peptococcus magnus to the Genus Peptostreptococcus and Proposal of Peptostreptococcus tetradius sp. nov.

EZAKI, TAKAYUKI, YAMAMOTO, NAOKI, NINOMIYA, KEIU, SUZUKI, SHOICHIRO, YABUUCHI, EIKO

International Journal of Systematic Bacteriology 1983; 33(4):683 · https://doi.org/10.1099/00207713-33-4-683

Download PDF View at publisher

Summary auto-generated

This 1983 systematic bacteriology study reclassified four Peptococcus species based on DNA analysis and biochemical characteristics. The researchers measured DNA base composition (G+C content) and DNA-DNA homology in anaerobic gram-positive cocci from clinical specimens. Peptococcus asaccharolyticus, P. indolicus, P. prevotii, and P. magnus all had G+C contents of 29-34 mol%, much closer to Peptostreptococcus anaerobius (33 mol%) than to Peptococcus niger (51 mol%), the respective type species. DNA-DNA homology between these four species and P. anaerobius ranged from 23-36%, while homology with P. niger was negligible. Cellular fatty acid profiles also resembled P. anaerobius more closely. Based on these molecular and biochemical findings, the authors transferred the four species to the genus Peptostreptococcus. Additionally, organisms previously called 'Gammya anaerobia' were identified as a distinct new species, Peptostreptococcus tetradius sp. nov., with type strain GIFU 7672. The study analyzed 262 strains total, demonstrating significant heterogeneity even within conventionally identified species, particularly P. asaccharolyticus and P. prevotii.

Key findings

  • Four Peptococcus species (asaccharolyticus, indolicus, prevotii, and magnus) were transferred to genus Peptostreptococcus based on G+C content similarity to P. anaerobius (29-34 mol%) rather than P. niger (51 mol%)
  • DNA-DNA homology values of 23-36% with Peptostreptococcus anaerobius and cellular fatty acid profiles supported the reclassification of these four species
  • Peptostreptococcus tetradius sp. nov. was formally named for organisms previously identified as 'Gammya anaerobia,' with strain GIFU 7672 as the type strain
  • DNA-DNA homology studies revealed substantial heterogeneity within P. asaccharolyticus and P. prevotii, with some clinical strains showing only 0-73% homology to type strains
  • Morphological features and carbohydrate fermentation patterns alone were insufficient to differentiate genera Peptococcus and Peptostreptococcus; molecular analysis was essential for accurate classification

This summary was generated automatically from the article PDF and is not part of the original publication. Refer to the PDF for the authoritative text.