The production of capsules, hyaluronic acid and hyaluronidase by 25 strains of group C streptococci.

Of the 25 group C streptococci examined all but 8 produced a hyaluronidase detectable in a sensitive turbidimetric test. These 8 strains and 6 of the hyaluronidase producers were heavily capsulated on serum glucose agar and in serum+glucose enriched liquid media. The capsules of all strains were readily destroyed by testicular hyaluronidase. In continually neutralized cultures of the capsulated strains hyaluronic acid was detected only transiently during logarithmic growth with the enzyme producers but rose to a high steady concentration with the other 3 strains. Hyaluronidase activity was present throughout the phase of logarithmic growth and beyond, but fell markedly in the 16 hr. following the cessation of logarithmic growth of capsulated strains in neutralized cultures and even more markedly in cultures grown without neutralization. Non-capsulated variants of the 9 capsulated organisms resembled the parent strains in enzyme production. A single passage through mice did not qualitatively influence capsulation, hyaluronic acid or hyaluronidase production by those strains examined.