Term: immunoglobulin (Ig)
https://doi.org/10.1351/goldbook.I02982

Definition:
A protein of the globulin-type found in serum or other body fluids that possesses antibody activity. An individual Ig molecule is built up from two light (L) and two heavy (H) polypeptide chains linked together by disulfide bonds. Igs are divided into five classes based on antigenic and structural differences in the H chains.

Related Terms:
1) serum (http://doi.org/10.1351/goldbook.ST06843).
2) antibody (http://doi.org/10.1351/goldbook.A00384).

Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 157 (https://doi.org/10.1351/pac199264010143)

Citation: 'immunoglobulin (Ig)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.I02982

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