Skip to main content
Protein Science : A Publication of the Protein Society logoLink to Protein Science : A Publication of the Protein Society
. 1993 Feb;2(2):175–182. doi: 10.1002/pro.5560020206

Mapping antibody binding sites on cytochrome c with synthetic peptides: are results representative of the antigenic structure of proteins?

C Schwab 1, A Twardek 1, T P Lo 1, G D Brayer 1, H R Bosshard 1
PMCID: PMC2142349  PMID: 7680266

Abstract

Crystallographic work on antigen-antibody complexes has revealed that extensive surface areas of proteins may interact with antibodies. On the other hand, most experimental approaches to locate and define antigenic determinants of protein antigens rely on the linear sequence of the polypeptide chain. Hence the question arises whether mapping of antibody binding sites by analysis of the reactivity of anti-protein antibodies with synthetic peptides can provide a representative picture of the antigenic structure of a protein antigen. We have addressed this question using yeast iso-1 cytochrome c as a protein antigen against which antisera were raised in rabbits. The reaction of the antisera with 103 synthetic hexapeptides covering the entire sequence of cytochrome c was tested by the pepscan procedure in which peptides are coupled to polyethylene rods and tested by ELISA. For the assay, anti-cytochrome c antibodies were fractionated by affinity chromatography on native yeast iso-1 cytochrome c and on apo-cytochrome c; the latter is a random coil. It was found that only antibodies retained by the apo-cytochrome c affinity column react with synthetic peptides. These antibodies comprise a small fraction, probably less than 2%, of all cytochrome c-specific antibodies. The majority of antigenic determinants, which seem to consist of strongly conformation-dependent topographic epitopes, could not be uncovered by the peptide approach. Epitope mapping with short peptides seems of limited usefulness in the case of small, globular, and conformationally stable proteins like cytochrome c.

Full Text

The Full Text of this article is available as a PDF (873.9 KB).

Selected References

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

  1. Alexander H., Alexander S., Getzoff E. D., Tainer J. A., Geysen H. M., Lerner R. A. Altering the antigenicity of proteins. Proc Natl Acad Sci U S A. 1992 Apr 15;89(8):3352–3356. doi: 10.1073/pnas.89.8.3352. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Benjamin D. C., Berzofsky J. A., East I. J., Gurd F. R., Hannum C., Leach S. J., Margoliash E., Michael J. G., Miller A., Prager E. M. The antigenic structure of proteins: a reappraisal. Annu Rev Immunol. 1984;2:67–101. doi: 10.1146/annurev.iy.02.040184.000435. [DOI] [PubMed] [Google Scholar]
  3. Berzofsky J. A., Schechter A. N. The concepts of crossreactivity and specificity in immunology. Mol Immunol. 1981 Aug;18(8):751–763. doi: 10.1016/0161-5890(81)90067-5. [DOI] [PubMed] [Google Scholar]
  4. Brautigan D. L., Ferguson-Miller S., Margoliash E. Mitochondrial cytochrome c: preparation and activity of native and chemically modified cytochromes c. Methods Enzymol. 1978;53:128–164. doi: 10.1016/s0076-6879(78)53021-8. [DOI] [PubMed] [Google Scholar]
  5. Carter J. M., Vanalbert S., Lee J., Lyon J., Deal C. Shedding light on peptide synthesis. Biotechnology (N Y) 1992 May;10(5):509–513. doi: 10.1038/nbt0592-509. [DOI] [PubMed] [Google Scholar]
  6. Connolly M. L. Solvent-accessible surfaces of proteins and nucleic acids. Science. 1983 Aug 19;221(4612):709–713. doi: 10.1126/science.6879170. [DOI] [PubMed] [Google Scholar]
  7. Damaschun G., Damaschun H., Gast K., Gernat C., Zirwer D. Acid denatured apo-cytochrome c is a random coil: evidence from small-angle X-ray scattering and dynamic light scattering. Biochim Biophys Acta. 1991 Jun 24;1078(2):289–295. doi: 10.1016/0167-4838(91)90571-g. [DOI] [PubMed] [Google Scholar]
  8. Das M. K., Lindstrom J. Epitope mapping of antibodies to acetylcholine receptor alpha subunits using peptides synthesized on polypropylene pegs. Biochemistry. 1991 Mar 5;30(9):2470–2477. doi: 10.1021/bi00223a025. [DOI] [PubMed] [Google Scholar]
  9. Fisher W. R., Taniuchi H., Anfinsen C. B. On the role of heme in the formation of the structure of cytochrome c. J Biol Chem. 1973 May 10;248(9):3188–3195. [PubMed] [Google Scholar]
  10. Geysen H. M., Mason T. J., Rodda S. J. Cognitive features of continuous antigenic determinants. J Mol Recognit. 1988 Feb;1(1):32–41. doi: 10.1002/jmr.300010107. [DOI] [PubMed] [Google Scholar]
  11. Geysen H. M., Meloen R. H., Barteling S. J. Use of peptide synthesis to probe viral antigens for epitopes to a resolution of a single amino acid. Proc Natl Acad Sci U S A. 1984 Jul;81(13):3998–4002. doi: 10.1073/pnas.81.13.3998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Geysen H. M., Tainer J. A., Rodda S. J., Mason T. J., Alexander H., Getzoff E. D., Lerner R. A. Chemistry of antibody binding to a protein. Science. 1987 Mar 6;235(4793):1184–1190. doi: 10.1126/science.3823878. [DOI] [PubMed] [Google Scholar]
  13. Houghten R. A. General method for the rapid solid-phase synthesis of large numbers of peptides: specificity of antigen-antibody interaction at the level of individual amino acids. Proc Natl Acad Sci U S A. 1985 Aug;82(15):5131–5135. doi: 10.1073/pnas.82.15.5131. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Krone W. J., Debouck C., Epstein L. G., Heutink P., Meloen R., Goudsmit J. Natural antibodies to HIV-tat epitopes and expression of HIV-1 genes in vivo. J Med Virol. 1988 Nov;26(3):261–270. doi: 10.1002/jmv.1890260306. [DOI] [PubMed] [Google Scholar]
  15. Lando G., Berzofsky J. A., Reichlin M. Antigenic structure of sperm whale myoglobin. I. Partition of specificities between antibodies reactive with peptides and native protein. J Immunol. 1982 Jul;129(1):206–211. [PubMed] [Google Scholar]
  16. Lando G., Reichlin M. Antigenic structure of sperm whale myoglobin. II. Characterization of antibodies preferentially reactive with peptides arising in response to immunization with the native protein. J Immunol. 1982 Jul;129(1):212–216. [PubMed] [Google Scholar]
  17. Louie G. V., Brayer G. D. High-resolution refinement of yeast iso-1-cytochrome c and comparisons with other eukaryotic cytochromes c. J Mol Biol. 1990 Jul 20;214(2):527–555. doi: 10.1016/0022-2836(90)90197-T. [DOI] [PubMed] [Google Scholar]
  18. Meloen R. H., Amerongen A. V., Hage-Van Noort M., Langedijk J. P., Posthumus W. P., Puyk W. C., Plasman H., Lenstra J. A., Langeveld J. P. The use of peptides to reconstruct conformational determinants; a brief review. Ann Biol Clin (Paris) 1991;49(4):231–241. [PubMed] [Google Scholar]
  19. Middeldorp J. M., Meloen R. H. Epitope-mapping on the Epstein-Barr virus major capsid protein using systematic synthesis of overlapping oligopeptides. J Virol Methods. 1988 Sep;21(1-4):147–159. doi: 10.1016/0166-0934(88)90061-4. [DOI] [PubMed] [Google Scholar]
  20. Paterson Y. Mapping antibody binding sites on protein antigens. Nature. 1992 Apr 2;356(6368):456–457. doi: 10.1038/356456a0. [DOI] [PubMed] [Google Scholar]
  21. Reichlin M., Nisonoff A., Margoliash E. Immunological activity of cytochrome c. 3. Enhancement of antibody detection and immune response initiation by cytochrome c polymers. J Biol Chem. 1970 Mar 10;245(5):947–954. [PubMed] [Google Scholar]
  22. Savoca R., Schwab C., Bosshard H. R. Epitope mapping employing immobilized synthetic peptides. How specific is the reactivity of these peptides with antiserum raised against the parent protein? J Immunol Methods. 1991 Aug 9;141(2):245–252. doi: 10.1016/0022-1759(91)90151-5. [DOI] [PubMed] [Google Scholar]
  23. Schwab C., Bosshard H. R. Caveats for the use of surface-adsorbed protein antigen to test the specificity of antibodies. J Immunol Methods. 1992 Feb 14;147(1):125–134. doi: 10.1016/s0022-1759(12)80037-8. [DOI] [PubMed] [Google Scholar]
  24. Smith M., Leung D. W., Gillam S., Astell C. R., Montgomery D. L., Hall B. D. Sequence of the gene for iso-1-cytochrome c in Saccharomyces cerevisiae. Cell. 1979 Apr;16(4):753–761. doi: 10.1016/0092-8674(79)90091-6. [DOI] [PubMed] [Google Scholar]
  25. Tainer J. A., Getzoff E. D., Alexander H., Houghten R. A., Olson A. J., Lerner R. A., Hendrickson W. A. The reactivity of anti-peptide antibodies is a function of the atomic mobility of sites in a protein. Nature. 1984 Nov 8;312(5990):127–134. doi: 10.1038/312127a0. [DOI] [PubMed] [Google Scholar]
  26. Tan X. H., Ratnam M., Huang S. M., Smith P. L., Freisheim J. H. Mapping the antigenic epitopes of human dihydrofolate reductase by systematic synthesis of peptides on solid supports. J Biol Chem. 1990 May 15;265(14):8022–8026. [PubMed] [Google Scholar]
  27. Van Regenmortel M. H. The concept and operational definition of protein epitopes. Philos Trans R Soc Lond B Biol Sci. 1989 Jun 12;323(1217):451–466. doi: 10.1098/rstb.1989.0023. [DOI] [PubMed] [Google Scholar]
  28. Westhof E., Altschuh D., Moras D., Bloomer A. C., Mondragon A., Klug A., Van Regenmortel M. H. Correlation between segmental mobility and the location of antigenic determinants in proteins. Nature. 1984 Sep 13;311(5982):123–126. doi: 10.1038/311123a0. [DOI] [PubMed] [Google Scholar]
  29. de Wolf F., Meloen R. H., Bakker M., Barin F., Goudsmit J. Characterization of human antibody-binding sites on the external envelope of human immunodeficiency virus type 2. J Gen Virol. 1991 Jun;72(Pt 6):1261–1267. doi: 10.1099/0022-1317-72-6-1261. [DOI] [PubMed] [Google Scholar]

Articles from Protein Science : A Publication of the Protein Society are provided here courtesy of The Protein Society

RESOURCES