Heavy chain variable domain

Renisio, J. G., Perez, J., Czisch, M., et al. (2002) Solution structure and backbone dynamics of an antigen-free heavy chain variable domain (VHH) from Llama. Proteins 47, 546-555. 

The exact position of the responsible subgroup-associated antigenic determinants within the heavy-chain variable domain is not yet clear. It seems obvious that they are not likely to be associated with the hypervariable regions (see below). Very probably they do involve, at least... 

The most remarkable feature of the antibody molecule is revealed by comparing the amino acid sequences from many different immunoglobulin IgG molecules. This comparison shows that between different IgGs the amino-terminal domain of each polypeptide chain is highly variable, whereas the remaining domains have constant sequences. A light chain is thus built up from one amino-terminal variable domain (Vl) and one carboxy-terminal constant domain (Cl), and a heavy chain from one amino-terminal variable domain (Vh), followed by three constant domains (Chi, Ch2. and Chs). 

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