Complementarity Determining Region II (CDR2) is a term used in molecular biology and immunology to refer to a specific region within the variable domain of an antibody. The variable domain is the part of the antibody that recognizes and binds to the specific target antigen.
The term "complementarity determining region" refers to the regions within the variable domain of the antibody that are responsible for recognizing and binding specifically to the target antigen. There are three complementarity determining regions, namely CDR1, CDR2, and CDR3.
CDR2 is the second of these three regions, and it plays a crucial role in the antigen-binding process. It is composed of amino acid residues located on the antibody's heavy and light chain that interact directly with the target antigen. The CDR2 region contributes to the overall shape, charge distribution, and conformational flexibility of the binding site, thereby influencing the antibody-antigen interaction.
The amino acid sequence of CDR2 is highly diverse, allowing for a broad range of target antigen recognition. It is involved in specific interactions with the target antigen through a combination of hydrogen bonds, van der Waals forces, and hydrophobic interactions.
Understanding the structure and function of CDR2 is important in studying and designing antibodies with specific binding properties. By manipulating the amino acid composition of CDR2, researchers can modify the binding affinity and specificity of antibodies, potentially leading to the development of more effective therapeutic antibodies for various diseases and conditions.
