Background: The wide range of antibody specificity and affinity results from the differing
shapes and chemical compositions of their binding sites. These shapes range from discrete
grooves in antibodies elicited by linear oligomers of nucleotides and carbohydrates to
shallow depressions or flat surfaces for accommodation of proteins, peptides and large
organic compounds. Objectives: To determine the Fab structure of a high-affinity human
antitoxin antibody. To explore structural features which enable the antibody to bind to intact …