Antibody Fab assembly: the interface residues between CH1 and CL.
The effective assembly of an antibody molecule requires the proper association of the light and heavy chains, namely the tight, canonical association of VH with VL, and of CH1 with CL. In this paper the interaction of CH1 is examined by looking at the degree of conservation of residues in the interface between CH1 and CL, where CH1 can belong to any of the heavy chain classes, and CL can be either lambda or kappa. The three-dimensional structures of four antibody Fabs have been examined to see which are the significant interacting residues and to see whether they also correspond to the conserved residues in the different classes. It was found that there are a few hydrophobic residues buried in the interface which make numerous contacts with residues of the other chain and which remain invariant, or else are highly conserved. Around the periphery of the interface there are numerous interacting residues that have appreciable variability. Within the interface there is a cavity, the function of which may be to permit some changes in the central interface residues while still preserving the same relative orientation of CH1 and CL.
D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D007127:Immunoglobulin Constant Regions; D007140:Immunoglobulin Fab Fragments; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D007136:Immunoglobulins; D051379:Mice; D008958:Models, Molecular
D007127:Immunoglobulin Constant Regions; D007140:Immunoglobulin Fab Fragments; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D007136:Immunoglobulins