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Publication Abstract from PubMed

The three-dimensional structure of an antibody (39-A11) that catalyzes a Diels-Alder reaction has been determined. The structure suggests that the antibody catalyzes this pericyclic reaction through a combination of packing and hydrogen-bonding interactions that control the relative geometries of the bound substrates and electronic distribution in the dienophile. A single somatic mutation, serine-91 of the light chain to valine, is largely responsible for the increase in affinity and catalytic activity of the affinity-matured antibody. Structural and functional studies of the germ-line precursor suggest that 39-A11 and related antibodies derive from a family of germ-line genes that have been selected throughout evolution for the ability of the encoded proteins to form a polyspecific combining site. Germ line-encoded antibodies of this type, which can rapidly evolve into high-affinity receptors for a broad range of structures, may help to expand the binding potential associated with the structural diversity of the primary antibody repertoire.

Immunological origins of binding and catalysis in a Diels-Alderase antibody.,Romesberg FE, Spiller B, Schultz PG, Stevens RC Science. 1998 Mar 20;279(5358):1929-33. PMID:9506942^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.