Structure of IgG "ππ»
.jpeg)
BASIC STRUCTURE OF IgG "ππ» Electron microscopic studies have revealed that IgG is a Y-shaped tetrapeptide protein formed of two identical light chains and two identical heavy chains. So an antibody is represented as H₂L₂ (1) Light Chains. Each light chain is formed of about 214 amino acids. Light chains are of two types in all the classes of immunoglobulin: Kappa (ΠΊ) and lambda (Ξ».) chains . A given antibody has either both Kappa or both lambda type light chains. The amino acid sequence analysis of light chains has shown that a light chain is formed of 2 parts: Variable (V) of 1-108 amino acids and varies from one antibody to another; and Constant (C) of 109-214 amino acids and is characteristic of the antibody. Each light chain also has two intrachain disulphide (S-S) loops, one in variable part and other in constant part. (2) Heavy Chains. These are two in number. Each heavy chain is formed of 440 amino acids. Each heavy chain is formed of two parts: Variable region (form...