Skip to main content
    • Aa
    • Aa

The cultural and biochemical characters of Streptococcus milleri strains isolated from human sources

  • Lyn C. Ball (a1) and M. T. Parker (a1)

A collection of 346 strains of Streptococcus milleri from a variety of human sources was examined culturally and biochemically, and for the presence of Lancefield group antigens. Most of the strains were non-haemolytic and ungroupable, but 25% were β haemolytic and 19% were α haemolytic; 28% possessed a group antigen (A, 5%; C, 6%, F, 14%, G, 3%). These antigens were present in 69% of β-haemolytic but in only 13% of α-haemolytic or non-haemolytic strains; β haemolysis occurred in 82% of group-F strains, 43% of other groupable strains and 11% of ungroupable strains.

The following reactions were given by > 80% of S. milleri strains: hydrolysis of arginine and aesculin, a positive Voges–Proskauer reaction, and acidification of trehalose, lactose, salicin and sucrose. A minority of strains showed enhancement of growth by CO2, bile tolerance, NaCl tolerance, and ability to acidify other sugars, notably mannitol, raffinose and melibiose. Departures from the modal pattern of biochemical reactions showed a weak correlation with the type of haemolysis and the presence or absence of a group antigen but were not sufficiently systematic for clear-cut subdivisions to be recognized within the species.

S. milleri therefore appeared to comprise a ‘central’ group of non-haemolytic strains that rarely formed a Lancefield-group antigen, in which the aesculin reaction was nearly always positive, lactose was usually acidified, and a considerable minority showed enhancement of growth by CO2 and bile tolerance. Deviations from this pattern were of two main types. (1) ‘Loss’ of one or more of these reactions, which tended to be associated with β-haemolysis and presence of a group antigen. In these respects, α-haemolytic strains tended to occupy an intermediate position. (2) ‘Gain’ of the ability to acidify additional sugars, notably raffinose and melibiose or mannitol; this occurred mainly among otherwise typical non-haemolytic strains that were rarely groupable.

Only 12% of isolations from the bloodstream of patients suffering from systemic infections were β haemolytic and only 18% possessed a group antigen, but a considerably greater proportion of those from visceral abscesses were β haemolytic (28%). Among isolations from superficial lesions in some body sites there were considerably greater proportions of β-haemolytic and groupable strains; thus, nearly one-half of those isolated from the abdomen other than the female genital tract were β-haemolytic and over one-half were groupable. On the other hand, strains from the teeth and gums were nearly always non-haemolytic and ungroupable, and most vaginal isolations were of non-haemolytic strains with a wide sugar-fermentation pattern.

Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

G. Colman (1968). The application of computers to the classification of streptococci. Journal of General Microbiology 50, 149–58.

G. Colman & R. E. O. Williams (1965). The cell walls of streptococci. Journal of General Microbiology 41, 375–87.

P. H. Long & E. A. Bliss (1934). Studies on minute hemolytic streptococci; isolation and cultural characteristics of minute beta hemolytic streptococci. Journal of Experimental Medicine 60, 619–31.

B. Mejàre & S. Edwardsson (1975). Streptococcus milleri (Guthof); an indigenous organism of the human oral cavity. Archives of Oral Biology 20, 757–62.

G. S. Mirick , L. Thomas , E. C. Curnen & F. L. Horsfall (1944). Studies on non-hemolytic streptococcus isolated from the respiratory tract of human beings. Journal of Experimental Medicine 80, 391406, 407–30, 431–40.

H. Ottens & K. C. Winkler (1962). Indifferent and haemolytic streptococci possessing group-antigen F. Journal of General Microbiology 28, 181–91.

M. T. Parker & L. C. Ball (1976). Streptococci and aerococci associated with systemic infection in man. Journal of Medical Microbiology 9, 275302.

I. Phillips , C. Warren , J. M. Harrison , P. Sharples , L. C. Ball & M. T. Parker (1976). Antibiotic susceptibilities of streptococci from the mouth and the blood of patients treated with penicillin or lincomycin and clindamycin. Journal of Medical Microbiology 9, 393404

P. M. Poole & G. Wilson (1977). Streptococcus milleri in the appendix. Journal of Clinical Pathology 30, 937–42.

F. R. Smith & J. M. Sherman (1938). The hemolytic streptococci of human feces. Journal of Infectious Diseases 62, 186–9.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 1 *
Loading metrics...

Abstract views

Total abstract views: 62 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 25th May 2017. This data will be updated every 24 hours.