The Antigenic Structure of Hemolytic Streptococci of Lancefield Group A

[摘要] 1. 1. Type-specific M substance has been extracted from undried, whole streptococci at 37°, 56° and 100°C. The M substance has also been extracted from the residues remaining after sonic disintegration of the organisms and extraction with saline.2. 2. M is a nucleoprotein which gives color tests for ribose but not for desoxyribose nucleic acid. Millon and Hopkins-Cole reactions are negative or very weakly positive. Ribonuclease produces detectable chemical, but not serological, alteration in preparations of M. A nucleic acid obtained from M was acted on by ribonuclease.3. 3. The inactivation of the type-specific precipitin reaction of M by trypsin has been confirmed and shown to take place within an unusually short time; simultaneously loss of precipitability with acid has been found to occur.4. 4. From tryptic digests of M a substance high in phosphorus, not a protein, can be precipitated with alcohol; from the alcoholic solution a biuret-positive, low-phosphorus, non-diffusible component is obtained.5. 5. The action of chlorine-water on M produces an acid-insoluble substance which is no longer reactive in the precipitin test. The presence of histidine and absence of tyrosine in M suggests that histidine is the site of this reaction.6. 6. The action of ribonuclease and color tests indicate that the nucleoprotein agglutinogen (NPA) contains both ribose and desoxyribose nucleic acids.7. 7. The action of trypsin on NPA was found to be accompanied by a loss of precipitability with acid at its flocculation point. A difference was found in the action of crystalline and commercial trypsin.8. 8. NPA has been shown to be more complex than M since it contains both ribose and desoxyribose nucleic acids and gives positive Millon and Hopkins-Cole reactions.

[学科分类] 生物科学（综合）