Comparison of the C-terminal Amino-acid Sequence of Two Horse Immunoglobulins IgG and IgG(T) (original) (raw)

Nature volume 212, pages 205–206 (1966) Cite this article

Abstract

IT was observed that treatment of the heavy chain of normal rabbit immunoglobulin G (IgG) with cyanogen bromide in 70 per cent formic acid split the chain into sections suitable for amino-acid sequence studies. Cyanogen bromide reacts with methionine residues converting them to homoserine with simultaneous splitting of the peptide chain and leaving the homoserine residue C-terminal1. Particularly the C-terminal octadecapeptide was easily isolated in high yield and its sequence was determined2. The heavy chain of human IgG from normal serum3 and a pathological serum4 both had the same C-terminal sequence and this differed from that of the rabbit in only two of the eighteen residues, suggesting that there might be a characteristic pattern for all mammalian IgG. The heavy chain of horse IgG has been investigated by the same technique and compared with the heavy chain of the horse T protein. The latter immunoglobulin is barely detectable in normal serum but increases very considerably in the serum of a horse strongly immunized with protein antigens such as diphtheria or tetanus toxoid and it may contain almost all the antibody5,6. This protein has a high carbohydrate content and it has been suggested that it might be the equine equivalent of human IgA. From a study of the antigenic cross-reactions of the whole proteins and their subunits, however, this seemed unlikely7.

This is a preview of subscription content, access via your institution

Access options

Subscribe to this journal

Receive 52 print issues and online access

$199.00 per year

only $3.83 per issue

Buy this article

USD 39.95

Prices may be subject to local taxes which are calculated during checkout

Additional access options:

Similar content being viewed by others

References

  1. Gross, E., and Witkop, B., J. Biol. Chem., 237, 1856 (1962).
    CAS PubMed Google Scholar
  2. Givol, D., and Porter, R. R., Biochem. J., 97, 32C (1965).
    Article CAS Google Scholar
  3. Piggot, P. J., and Press, E. M., Biochem. J., 99, 16P (1966).
    Article CAS Google Scholar
  4. Press, E. M., Piggot, P. J., and Porter, R. R., Biochem. J., 99, 356 (1966).
    Article CAS Google Scholar
  5. Kekwick, R. A., and Record, B. R., Brit. J. Exp. Path., 22, 29 (1941).
    CAS Google Scholar
  6. Van der Scheer, J., and Wyckoff, R. W. G., Proc. Soc. Exp. Biol. Med., 43, 427 (1940).
    Article CAS Google Scholar
  7. Weir, R. C., and Porter, R. R., Biochem. J., 100, 63 (1966).
    Article CAS Google Scholar
  8. Prahl, J. W., Proc. Roy. Soc., B, 166, 108 (1966).
    Google Scholar
  9. Cebra, J. J., and Robbins, J. B., J. Immunol., 97, 12 (1966).
    CAS PubMed Google Scholar
  10. Cebra, J. J., and Small, P. A., Biochemistry (in the press).

Download references

Author information

Author notes

  1. R. C. WEIR: Department of Chemical Pathology, Guy's Hospital Medical School London, S.E.1.
  2. D. GIVOL: The Weizmann Institute, Rehovoth, Israel.

Authors and Affiliations

  1. Department of Immunology, St. Mary's Hospital Medical School, London, W.2
    R. C. WEIR, R. R. PORTER & D. GIVOL

Authors

  1. R. C. WEIR
  2. R. R. PORTER
  3. D. GIVOL

Rights and permissions

About this article

Cite this article

WEIR, R., PORTER, R. & GIVOL, D. Comparison of the C-terminal Amino-acid Sequence of Two Horse Immunoglobulins IgG and IgG(T).Nature 212, 205–206 (1966). https://doi.org/10.1038/212205a0

Download citation