Labeling of immunoglobulins with bifunctional, sulfhydryl-selective, and photoreactive coumarins.
4-(Bromomethyl)-6,7-dimethoxy-2-oxo-2H-benzopyran (1a) and 4-(bromomethyl)-7-methoxy-2-oxo-2H-benzopyran (1b) and their iodo analogs (2) reacted selectively with the sulfhydryl groups generated in a limited reduction of the hinge disulfide bonds of an immunoglobulin G (IgG) giving proteins labeled with a fluorescent and/or radioactive moiety. Quantitative alkylation of free thiol groups was obtained with 1 and 125/127I-2. Photodimerization of these adducts produced IgG with covalently joined heavy chains.
Baranowska-Kortylewicz
J
J
Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115.
Kassis
A I
AI
D000327:Adsorption; D003374:Coumarins / Q000737:chemistry*; D003545:Cysteine / Q000737:chemistry; D007074:Immunoglobulin G / Q000737:chemistry; D007136:Immunoglobulins / Q000737:chemistry*; D007202:Indicators and Reagents; D010084:Oxidation-Reduction; D010777:Photochemistry; D017510:Protein Folding; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D014468:Umbelliferones / Q000737:chemistry
D003374:Coumarins; D007074:Immunoglobulin G; D007136:Immunoglobulins; D007202:Indicators and Reagents; D013438:Sulfhydryl Compounds; D014468:Umbelliferones; C000317:4-bromomethyl-7-methoxycoumarin; C053769:4-bromomethyl-6,7-dimethoxycoumarin; D003545:Cysteine