Abstract
Amino acid sequences around the disulphide bridges of the heavy chain of an immunoglobulin of the γ2 subclass have been studied. The protein was digested with pepsin and the digest fractionated by Sephadex. Screening of the eluate by one-dimensional electrophoresis of oxidized and unoxidized samples was used as an assay and pools of fractions were prepared. Identification by diagonal electrophoresis of several inter- and intra-chain disulphide bridges was done on the pooled fractions. The inter-heavy-chain bridged peptide included four cystine residues. Comparison with proteins of other human subclasses indicated that the intrachain bridges identified are the bridges of the invariable section of γ2 heavy chains. The amino acid sequence of one cysteic acid peptide that may have been derived from the variable part of the molecule was determined. Partial reduction followed by carboxymethylation with radioactive iodoacetate of two proteins of the γ2 class showed a number of labelled peptides that could be identified as being related to the inter-chain bonded cystine residues.
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- AMBLER R. P. THE AMINO ACID SEQUENCE OF PSEUDOMONAS CYTOCHROME C-551. Biochem J. 1963 Nov;89:349–378. doi: 10.1042/bj0890349. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Crowshaw K., Jessup S. J., Ramwell P. W. Thin-layer chromatography of 1-dimethylaminonaphthalene-5-sulphonyl derivatives of amino acids present in superfusates of cat cerebral cortex. Biochem J. 1967 Apr;103(1):79–85. doi: 10.1042/bj1030079. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frangione B., Franklin E. C., Fudenberg H. H., Koshland M. E. Structural studies of human gamma-G-myeloma proteins of different antigenic subgroups and genetic specificities. J Exp Med. 1966 Oct 1;124(4):715–732. doi: 10.1084/jem.124.4.715. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frangione B., Milstein C., Franklin E. C. Intrachain disulphide bridges in immunoglobulin G heavy chains. The Fc fragment. Biochem J. 1968 Jan;106(1):15–21. doi: 10.1042/bj1060015. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frangione B., Milstein C., Pink J. R. Structural studies of immunoglobulin G. Nature. 1969 Jan 11;221(5176):145–148. doi: 10.1038/221145a0. [DOI] [PubMed] [Google Scholar]
- Grey H. M., Kunkel H. G. Heavy-chain subclasses of human gamma-G-globulin. Peptide and immunochemical relationships. Biochemistry. 1967 Aug;6(8):2326–2334. doi: 10.1021/bi00860a007. [DOI] [PubMed] [Google Scholar]
- Milstein C. The disulphide bridges of immunoglobulin kappa-chains. Biochem J. 1966 Nov;101(2):338–351. doi: 10.1042/bj1010338. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Donnell I. J., Frangione B., Porter R. R. The disulphide bonds of the heavy chain of rabbit immunoglobulin G. Biochem J. 1970 Jan;116(2):261–268. doi: 10.1042/bj1160261. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pink J. R., Buttery S. H., De Vries G. M., Milstein C. Human immunoglobulin subclasses. Partial amino acid sequence of the constant region of a gamma 4 chain. Biochem J. 1970 Mar;117(1):33–47. doi: 10.1042/bj1170033. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Prahl J. W. The C-terminal sequences of the heavy chains of human immunoglobulin G myeloma proteins of differing isotopes and allotypes. Biochem J. 1967 Dec;105(3):1019–1028. doi: 10.1042/bj1051019. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Terry W. D. Skin-sensitizing activity related to gamma- polypeptide chain characteristics of human IgG. J Immunol. 1965 Dec;95(6):1041–1047. [PubMed] [Google Scholar]
- Woods K. R., Wang K. T. Separation of dansyl-amino acids by polyamide layer chromatography. Biochim Biophys Acta. 1967 Feb 21;133(2):369–370. doi: 10.1016/0005-2795(67)90078-5. [DOI] [PubMed] [Google Scholar]

