PEPTOCOCCUS

SPECIES

MICROSCOPIC APPEARANCE

Gram Stain: Gram-positive.
Morphology: Spherical, arrangement is variable: in pairs, tetrads, clumps, or short chains.
Size: 0.3 micrometers by 1.2 micrometers.
Motility: Non-motile.
Capsules: No.
Spores: No.

MICROSCOPIC APPEARANCE

Species often form black colonies to olive green colonies on initial isolation. The black pigment fades quickly upon exposure to oxygen and within a week some colonies take on a mustard yellow pigmentation. The colonies are convex, circular, and have a shiny, smooth appearance.

KEY BIOCHEMICAL REACTIONS

METABOLIC PROPERTIES

Anaerobic, Chemoorganotrophic, having a fermentative metabolism and requiring nutritionally rich media. Carbohydrates are not attacked, and H 2 is produced from peptone.

HABITAT

Skin of umbilicus and genital area, occasionally present in clinical specimens.

PATHOGENICITY

Obligate parasites of human mucous membranes. Non-pathogenic to humans and other animals.

RECOMMENDED MEDIA

For culture: Brucella with H & K and Cooked Meat Medium.
For selective isolation: None described.
For maintenance: Cooked Meat Medium, Skim Milk Medium, or Brucella with Glycerol. Lyophilization is required for long-term preservation.

INCUBATION

Temperature: 37 degrees C.
Time: 24-48 hours.
Atmosphere: Anaerobic.

REFERENCES

1. Holt, J.G., et al. 1994. Bergey's Manual of Determinative Bacteriology , 9th ed. Williams & Wilkins, Baltimore, MD.

2. Holt, J.G., et al. 1986. Bergey's Manual of Systemic Bacteriology , Vol. I & II. Williams & Wilkins, Baltimore, MD.

3. The Oxoid Vade-Mecum of Microbiology . 1993. Unipath Ltd., Basingstoke, UK.

4. Murray, P.R., et al. 1995. Manual of Clinical Microbiology , 6th ed. American Society for Microbiology, Washington, D.C.

5. Internet: www.hardlink.com /Bacterial Database Search, February, 1998.

6. Hensyl, B.R., et al. 1990. Stedman's Medical Dictionary , 25th ed. Williams & Wilkins, Baltimore, MD.

7. Koneman, et al. 1997. Color Atlas and Textbook of Diagnostic Microbiology , 5th ed. Lippincott, Philadelphia, PA.


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