1ind

HOW THE ANTI-(METAL CHELATE) ANTIBODY CHA255 IS SPECIFIC FOR THE METAL ION OF ITS ANTIGEN: X-RAY STRUCTURES FOR TWO FAB'(SLASH)HAPTEN COMPLEXES WITH DIFFERENT METALS IN THE CHELATE

spinqualitylabelsall models 1ind, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1ind is a 2 chain structure with sequence from Mus musculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.2Å Ligands: EOT, IN, PCA Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Antibodies with bound metal-chelate haptens provide new means for exploiting the diverse properties of metallic elements. The murine monoclonal antibody CHA255 (IgG1 lambda) binds the metal-chelate hapten indium (III)-4-[N'-(2-hydroxyethyl)thioureido]-L-benzyl-EDTA (designated In-EOTUBE) with high affinity (K(a) = 1.1 x 10(10) M-1). Antibody binding is highly specific for the indium chelate; the affinity decreases as much as 10(4) with other metals, even those having ionic radii close to indium. To better understand this selectivity, the crystal structure of the antigen-binding fragment (Fab') of CHA255 complexed with its hapten, In(III)-EOTUBE, was determined by molecular replacement and refined at 2.2-A resolution. The structure of CHA255 Fab' complexed with Fe(III)-EOTUBE was also determined and refined at 2.8-A resolution. In both structures, the hapten's EDTA moiety is half-buried near the center of the complementarity-determining regions (CDR's). Five of the six CDR's on the Fab' interact with the hapten through protein side-chain atoms (but not main-chain atoms). A novel feature of the In-EOTUBE/Fab' complex is coordination of the indium by N epsilon of one histidine from the heavy chain's third CDR (distance = 2.4 A). The histidine coordination is not observed in the Fe-EOTUBE/Fab' complex, due mainly to a slightly different hapten conformation that reduces metal accessibility; this may partially explain the 20-fold lower affinity of CHA255 for iron hapten. An unexpected feature of the Fab' overall is an elbow angle of 193 degrees (the angle between the pseudodyad axes of the Fab's constant and variable domains). How the anti-(metal chelate) antibody CHA255 is specific for the metal ion of its antigen: X-ray structures for two Fab'/hapten complexes with different metals in the chelate.,Love RA, Villafranca JE, Aust RM, Nakamura KK, Jue RA, Major JG Jr, Radhakrishnan R, Butler WF Biochemistry. 1993 Oct 19;32(41):10950-9. PMID:8218161 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Antibody 3D structures Sandbox 20009 3D structures of non-human antibody

Proteopedia Page Contributors and Editors (what is this?)

OCA