Mechanism of the Non-specific Serum Agglutination of the Obligate Anaerobes Clostridium paraputrificum and Clostridium capitovalis.

Non-specific reactions in agglutination tests have long provided trouble for the bacteriologist. One of the chief offenders has been spontaneous agglutination. The pseudo-reactions obtained in the serologic agglutination of the obligate anaerobes Clostridium paraputrificum (1934) and Clostridium capitovalis (1935), however, were not considered as due to spontaneous agglutination, but rather to the acid produced in the glucose broth cultures used. When the acid was eliminated it was easy to differentiate, these species on the basis of agglutination. At first it was thought that acid alone was responsible for the cross-agglutinations occurring when glucose broth cultures of these species were tested against heterologous serums. It was found, however, that a constituent of the broth was also a contributing factor. The relation of these serum-broth-acid reactions to the acid agglutinations described by Michaelis (1911) was also studied.