An IgG protein contains two copies of a large polypeptide he

An IgG protein contains two copies of a large polypeptide (heavy chain) and two copies of a small polypeptide (light chain). structure contributes significantly to the tertiary structure of domains of both chains. Disulfide bonds link the heavy chains to one another and to the light chains. The chains are arranged in a Y-shaped structure where the two arms are linked to the base by a protease sensitive (“hinge”) region. a. Describe the chemical properties that determine how an antibody binds its target. How do these properties apply to the specificity of an antibody? (5 points) b. Which model of ligand binding best describes antibody binding? Justify your answer with specific examples with citations. (10 points) c. Describe one biochemical application of antibodies. Focus on how they work, when and why you would use them, and how to read the results, not just the name of the technique. Be sure to incorporate the chemical principles described in (a) in your answer. (10 points)

Solution

Antibody is one of the important arm for immunsystem to defence agains foreign molecules that are harmfull or may not be. Antibody have two chain one is heavy chain and one is light chain. Along with these it has FAB REGION and FC REGION.

FAB REGION its an very important part of the Antibody because it contain variable region that binds to the antigen and initiate immune reactions.

When antigen were processed and presented by MHC molecule to B cell receptor particular antibody that conta BINDING ABILITY TO THAT ANTIGEN VIA VARIATION in variable region of it.

Via gene rerrangement the variable region will create binding pocket for the antigen protien, via gene rearrangement antibody show extremely large diversity. So variable region were varies with ANTIGEN SPECIFIC STRUCTURES.

Fc region its tail prtion of the antibody it play important part in cell suface binding via Fc receptors and also play important part in complement sysytem for the bacterial killing or opsonization. Its a constant region it does nto varies as FAB region does.

Application of antibody:-

Antibodys are used to detect certaion minute concentration antigenic virus or protien..How ? By producing antibody against these antigen or protein we cam detect by tagging antibody labelling for exmple determinaation of HIV infection BY ELISA test. in which we lablled antibody with fouroscent take or enzyme that gives us product.

We can estimate concentarion of antigen by lalbelling particular antibody with enzyme as we do in ELISA TEST , to identify mumps , rubella, Hepatites B virus