A redox function for the Calpha2 domain of IgA immunoglobulin.

M Fontaine; J Rousseaux; J Bourguignon; C Rivat; M Dantant; M Dautrevaux

doi:10.1016/0005-2795(81)90149-5

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A redox function for the Calpha2 domain of IgA immunoglobulin.

M Fontaine·J Rousseaux·J Bourguignon·C Rivat·M Dantant·M Dautrevaux

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Abstract

IgA1 populations were reduced over a range of dithiothreitol concentrations and the products were examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and peptide mapping. The study showed that IgA was more resistant to reduction than other immunoglobulin classes (IgG, IgM). SDS-polyacrylamide gel electrophoresis showed that intersubunit bond and H-L bond were the most labile disulfide in polymeric and monomeric IgA, respectively. Peptide mapping revealed that the itrachain disulfide of the C alpha 2 domain was more or equally sensitive to the reduction than H-L and intersubunit bonds. Electrochemical experiments demonstrated that this bond had redox properties and the possibility involving disulfide exchange is discussed.

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Chemical Phenomena Chemistry Disulfides Dithiothreitol Humans Immunoglobulin A Immunoglobulin Constant Regions Immunoglobulin Fragments Immunoglobulin Heavy Chains Immunoglobulin Light Chains Immunoglobulins Oxidation-Reduction Comparative Study Journal Article Research Support, Non-U.S. Gov't

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M Fontaine, J Rousseaux, J Bourguignon, C Rivat, M Dantant, M Dautrevaux. 1981-03-27. A redox function for the Calpha2 domain of IgA immunoglobulin.. https://doi.org/10.1016/0005-2795(81)90149-5

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