Phylum Firmicutes, Class Bacilli, Order Lactobacillales, Family Streptococcaceae, Genus Streptococcus, Streptococcus ratti
Coykendall 1977 (the original spelling "rattus", has been corrected by Trüper and De' Clari 1997).
Basonym: S. mutans subsp. rattus Coykendall 1974.
No reaction with Lancefield antisera.
Gram-positive, slightly elongated cocci, 0.5 μm in diameter, occurring in pairs and
Colonies on agar containing sucrose are ~ 1 mm in diameter, rough, and heaped,
and may have beads or puddles of liquid (containing glucan) around. Colonies on
Trypticase-soy agar are gray-white and opaque, with a raised center. Nonhemolytic on
blood agar. Grow at 37.0 ºC; can grow at 45 but not at 10 ºC. Growth occurs in air and
is enhanced in low oxygen atmosphere. A pH of 4.2 to 4.4 was produced from
carbohydrates. Intolerant of 40% bile and 6.5% NaCl.
First isolated from a laboratory rat which may have been infected through contact with humans. Not found in wild rats.
- Holt J.G., Krieg N.R., Sneath P.H.A., Staley J.T. and Williams S.T., 1994. Bergey's Manual of Determinative Bacteriology, Ninth
Edition, Williams & Wilkins, A Waverly Company, Baltimore, pp 527-558.
- Robert A. Whiley and Jeremy M. Hardie, 2009. Genus I. Streptococcus Rosenbach 1884, 22AL. In: (Eds.) P.D. Vos, G. Garrity, D.
Jones, N.R. Krieg, W. Ludwig, F.A. Rainey, K.-H. Schleifer, W.B. Whitman. Bergey’s Manual of Systematic Bacteriology, Volume 3:
The Firmicutes, Springer, 655-711.
- Coykendall A.L.: Proposal to elevate the subspecies of Streptococcus mutans to species status, based on their molecular
composition. International Journal of Systematic Bacteriology, 1977, 27, 26-30.
- Kazuko Takada, Kazuhiko Hayashi, Yutaka Sato, and Masatomo Hirasawa. Streptococcus dentapri sp. nov., isolated from the wild
boar oral cavity. Int J Syst Evol Microbiol April 2010 60:820-823.
- Truper H.G. and De' Clari L): Taxonomic note: Necessary correction of specific epithets formed as substantives (nouns) "in
apposition". Int. J. Syst. Bacteriol., 1997, 47, 908-909.
Positive results for arginine hydrolysis, esculin hydrolysis, Voges-Proskauer reaction, acid production from: amygdalin, arbutin,
cellobiose, methyl D-glucoside, N-acetylglucosamine, galactose, glucose, inulin (most strains), lactose (most strains), maltose,
mannitol, melibiose (most strains), raffinose, salicin, sorbitol, sucrose & trehalose. An adhesive extracellular glucan is produced from
Negative results for hippurate hydrolysis, strach hydrolysis, urease, acid production from: adonitol, arabinose, dulcitol, erythritol,
glycerol, glycogen, inositol, melezitose, methyl D-mannoside, methyl D-xyloside, rhamnose, ribose, sorbose, starch & xylose.
Hydrogen peroxide is not produced.
(c) Costin Stoica