Streptococcus porcinus
Cultural characteristics
Biochemical characters
Phylum Firmicutes, Class Bacilli, Order Lactobacillales, Family Streptococcaceae, Genus Streptococcus, Streptococcus porcinus  
Collins et al. 1985.
Lancefield group E, P, U & V.
Gram-positive cocci, grouped in short chains, nonmotile.
Beta-hemolytic, small, regular, non-pigmented colonies. CAMP test is positive. Grow
at 37.0 ºC, but not at 10 or 45 ºC.
Require complex media (Trypticase soy agar with defibrinated sheep blood), growth
is enhanced by CO
2 presence.
Isolated mainly from the upper respiratory tract of swine (tonsils, pharynx, nose), rarely from vaginal secretions or sperm. Few strains
isolated from other species. Some female genitourinary tract isolates from humans, identified as
S. porcinus, changed to S.
by 16S RNA gene analysis.
Does not survive heating at 60 ºC for 30 minutes.
Produce streptococcal lymphadenitis of swine (jowl abscesses, cervical abscesses, feeder boils or swine strangles). Rarely may
cause septicemia,  endocarditis, pericarditis, meningitis, encephalitis, pneumonia, tracheitis, otitis media, enteritis, arthritis, abortus,
and  mammitis.
  1. 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.
  2. Collins M.D., Farrow J.A.E., Katic V. & Kandler O.: Taxonomic studies on streptococci of serological groups E, P, U and V:
    description of Streptococcus porcinus sp. nov. Syst. Appl. Microbiol. 1984, 5, 402-413.
  3. R. Facklam, J. Elliott, N. Pigott & A.R. Franklin: Identification of Streptococcus porcinus from human sources. Journal of Clinical
    Microbiology, Feb 1995, 385-388, Vol 33, No. 2.
  4. Rafael S. Duarte, Rosana R. Barros, Richard R. Facklam & Lucia M. Teixeira: Phenotypic and Genotypic Characteristics of
    Streptococcus porcinus Isolated from Human Sources. Journal of Clinical Microbiology, September 2005, p. 4592-4601, Vol. 43,
    No. 9.
  5. 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.
Positive results for alkaline phosphatase, arginine hydrolysis, leucine arylamidase,
acid production from: N-acetylglucosamine, fructose, galactose, glucose, mannose,
ribose, sorbitol & trehalose. Most strains hydrolyze gelatin if incubated anaerobically.

Negative results for alpha-galactosidase, beta-galactosidase, hippurate hydrolysis, pyrrolidonyl arylamidase, acid production from: D-
or L-arabinose, D- or L-arabitol, adonitol, dulcitol, erythritol, D- or L-fucose, gluconate, glycogen, inositol, inulin, 2- or 5-ketogluconate,
lyxose, melezitose, melibiose, methyl alpha-D-glucoside, methyl alpha-D-mannoside, raffinose, rhamnose, L-sorbose, tagatose, D-
turanose, xylitol, D- or L-xylose.

Variable results for beta-glucuronidase, esculin hydrolysis, Voges–Proskauer reaction, acid production from: amygdalin, cellobiose,
glycerol, lactose, mannitol, maltose, salicin, starch & sucrose.
(c) Costin Stoica
Culture media
Biochemical tests
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