Smith, Doyle C. (Kansas State University, Manhattan), V. D. Foltz, and T. H. Lord. Demonstration of induced synergistic hemolysis by "non-hemolytic" Staphylococcus species. J. Bacteriol. 87:188-195. 1964.-The synergistic hemolysis of "normally nonhemolytic" staphylococci on blood-agar incubated in, or adjacent to, a secondary zone of certain hemolytic staphylococci is described. The synergism apparently results from the combining of two factors, Z, produced by hemolytic staphylococci that elaborate a secondary zone, and T, produced by "nonhemolytic" staphylococci. The production of the two factors is substantiated by (i) the absence of clear hemolysis around nonhemolytic colonies and in the secondary zone of hemolytic colonies, and by (ii) evidence of clear hemolysis when the secondary zone reaches to within a few millimeters, and finally surrounds, the nonhemolytic colonies. It was possible to show on a blood-agar plate containing a mixture of both hemolytic and nonhemolytic cultures that all colonies exhibited a zone of clear hemolysis. When 400 colonies were selected from such a blood plate, 280 were nonhemolytic on subsequent studies. The remaining 120 colonies were hemolytic. Thus, there is danger of confusing non-hemolytic Staphylococcus colonies, showing induced hemolysis, with truly hemolytic colonies. If a similar situation occurred on a diagnostic blood plate, it could very likely result in failure to identify a possibly pathogenic staphylococcus.

Agar↗

PubMed1964

TWO LYTIC FACTORS INVOLVED IN INDUCED SYNERGISTIC HEMOLYSIS IN NORMALLY NONHEMOLYTIC STAPHYLOCOCCI.

Smith, Doyle C. (Kansas State University, Manhattan), V. D. Foltz, and T. H. Lord. Two lytic factors involved in induced synergistic hemolysis in normally nonhemolytic staphylococci. J. Bacteriol. 88:1700-1704. 1964.-Synergistic hemolysis of "normally nonhemolytic" staphylococci results from the combination of two factors: Z, produced by hemolytic staphylococci that elaborate a secondary hemolytic zone on blood-agar, and T, produced by nonhemolytic staphylococci. Factors Z and T are produced in supernatant fluids of broth cultures and are detected by the synergistic hemolysis (SH) test. Complete lysis of sheep red cells is observed in the SH test only when both factors Z and T are present. Production of Z and T is greatly enhanced by the presence of 10 or 20% CO(2) during incubation. Both Z and T are heat-stable, withstanding 100 C for 15 min. Neither factor is precipitated by saturated Na(2)SO(4) or (NH(4))(2)SO(4). Hydrogen ion concentrations between pH 5.0 and 8.5 do not exert any effect on the two factors. Factor Z is produced in greater quantity than factor T. It is suggested that factors Z and T are not proteinaceous, enzymatic, or lipid in nature.

Ammonium Compounds↗

PubMed1964