An Improved Medium for the Cultivation of Hemolytic Streptococcus

Abstract

In the preceding paper (Bernheimer and Pappenheimer, 1942) the factors necessary for massive growth of group A hemolytic streptococcus on a medium of essentially defined chemical composition were discussed. The medium has been adapted for heavy growth in large volumes. Although worked out specifically for the C203S strain, the medium has proved useful for the cultivation of other strains of group A streptococcus. The following solutions are prepared: Solution I: 10 liters of distilled water (Note 1), 7.5 grams MgSO4. 7H20, 150 mgm. uracil, 150 mgm. adenine sulfate and 110 mgm. phenol red are placed in a 20 liter Pyrex carboy and sterilized at 15 lbs. for 90 minutes in the autoclave. Solution II: To 3 liters of 10 per cent casein hydrolysate (Note 2) are added 2 grams cystine (dissolved separately in water with the aid of a little concentrated HCl), 45 grams KCl, 37.5 grams KH2PO4, 15 grams

A Partially Defined Medium for Cultivation of Pneumococcus

“…They noted difficulty in the subculture of certain strains on this medium. Badger (1944) also found the medium of Rane and Subbarow to be inadequate for several strains of pneumococcus, and in investigating the nutritional requirements of a strain of pneumococcus type III developed a medium similar to that of Bohonos and Subbarow and similar in most respects to media developed for the cultivation of group A hemolytic streptococci by Bernheimer et al (1942) and by Woolley (1941).…”

“…All of these media for pneumococcus contain a reducing agent such as ascorbic acid (Badger, 1944), or thioglycollic acid (Bernheimer et at., 1942), in accordance with the findings of Dubos (1929) that a lowered redox potential is essential for 42ARK I1. ADANIS A'ND AMY S. ROE the initiation of growth of the pneumococcus.…”

“…EXPERIMENTAL Medium. Since the medium of Rane and Subbarow (1940) proved to be unsuitable for the cultivation of our strains of pneumococcus, we turned to the medium of Bernheimer et al (1942), designed for the growth of the C203S strain of hemolytic streptococcus group A. This medium was prepared using an acid hydrolyzate of Harris' vitamin-free casein as a base in place of the acid digest of technical casein used for streptococcus.…”

“…Test of Medium. Ten strains of pneumococci were tested on the casein hydrolyzate medium of Bernheimer et al (1942), made up as above, but lacking choline and asparagine. Growth was absent or scanty on first inoculation in the medium, and no strain grew on second transfer.…”

“…Tillett, Cambier, and Harris (1943) used the pneumococcus medium, prepared with casamino acids low in inhibitor, in testing sulfonamide-fast strains of pneumococcus for their ability to synthesize sulfonamide inhibitors. They refer to it as the medium of Bernheimer et al (1942). It should be noted that choline and asparagine were also present in the medium which they used.…”