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. 1974 May;9(5):891–896. doi: 10.1128/iai.9.5.891-896.1974

Peptic Digestion of Streptococcal M Protein II. Extraction of M Antigen from Group A Streptococci With Pepsin

Edwin H Beachey 1, Gary L Campbell 1, Itzhak Ofek 1
PMCID: PMC414902  PMID: 4132911

Abstract

M protein of group A streptococci was extracted by mild peptic digestion. Optimal amounts of type-specific M protein were released after 20 min of digestion with 0.02 mg of pepsin per ml at pH 5.8. Immunological analysis revealed that, unlike conventional HCl extracts, pepsin extracts lacked the surface C carbohydrate antigen and contained less non-type-specific, heat-stable cellular antigens; they also lacked detectable heat-labile T protein. Similar to HCl extracts, however, the pepsin-extracted M protein precipitated homologous-type M antisera and inhibited type-specific opsonization of homologous group A streptococci. Furthermore, the pepsin extract was capable of inducing type-specific opsonic M antibody in rabbits. This method may provide a useful initial step in the purification of M protein by reducing contaminating antigens.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Beachey E. H., Alberti H., Stollerman G. H. Delayed hypersensitivity to purified streptococcal m protein in guinea pigs and in man. J Immunol. 1969 Jan;102(1):42–52. [PubMed] [Google Scholar]
  2. Beachey E. H., Cunningham M. Type-specific inhibition of preopsonization versus immunoprecipitation by Streptococcal M proteins. Infect Immun. 1973 Jul;8(1):19–24. doi: 10.1128/iai.8.1.19-24.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Beachey E. H., Ofek I., Bismo A. L. Studies of antibodies to non-type-specific antigens associated with streptococcal M protein in the sera of patients with rheumatic fever. J Immunol. 1973 Nov;111(5):1361–1366. [PubMed] [Google Scholar]
  4. Beachey E. H., Stollerman G. H. Mediation of cytotoxic effects of streptococcal M protein by nontype-specific antibody in human sera. J Clin Invest. 1973 Oct;52(10):2563–2570. doi: 10.1172/JCI107448. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Beachey E. H., Stollerman G. H. Toxic effects of streptococcal M protein on platelets and polymorphonuclear leukocytes in human blood. J Exp Med. 1971 Aug 1;134(2):351–365. doi: 10.1084/jem.134.2.351. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Besdine R. W., Pine L. Preparation and description of high-molecular-weight soluble surface antigens from a group A Streptococcus. J Bacteriol. 1968 Dec;96(6):1953–1960. doi: 10.1128/jb.96.6.1953-1960.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Cunningham M. W., Beachey E. H. Peptic digestion of streptococcal M protein. I. Effect of digestion at suboptimal pH upon the biological and immunochemical properties of purified M protein extracts. Infect Immun. 1974 Feb;9(2):244–248. doi: 10.1128/iai.9.2.244-248.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Fox E. N., Wittner M. K. New observations on the structure and antigenicity of the M proteins of the group A streptococcus. Immunochemistry. 1969 Jan;6(1):11–24. doi: 10.1016/0019-2791(69)90174-8. [DOI] [PubMed] [Google Scholar]
  9. LANCEFIELD R. C. Current knowledge of type-specific M antigens of group A streptococci. J Immunol. 1962 Sep;89:307–313. [PubMed] [Google Scholar]
  10. LANCEFIELD R. C., PERLMANN G. E. Preparation and properties of type-specific M antigen isolated from a group A, type 1 hemolytic streptococcus. J Exp Med. 1952 Jul;96(1):71–82. doi: 10.1084/jem.96.1.71. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Ne'eman N., Ginsburg I. Red cell-sensitizing antigen of group A streptococci. I. Biological and chemical properties. Isr J Med Sci. 1972 Nov;8(11):1799–1806. [PubMed] [Google Scholar]
  12. Pachman L. M., Fox E. N. Cellular and antibody reactions to streptococcal M protein types 1, 3, 6 and 12. J Immunol. 1970 Oct;105(4):898–907. [PubMed] [Google Scholar]
  13. Rotta J., Krause R. M., Lancefield R. C., Everly W., Lackland H. New approaches for the laboratory recognition of M types of group A streptococci. J Exp Med. 1971 Nov 1;134(5):1298–1315. doi: 10.1084/jem.134.5.1298. [DOI] [PMC free article] [PubMed] [Google Scholar]

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