What is the domain of an antibody?

What is the domain of an antibody?

Antibodies all have the same basic structure consisting of two heavy and two light chains forming two Fab arms containing identical domains at either end attached by a flexible hinge region to the stem of the antibody, the Fc domain, giving the classical ‘Y’ shape.

What are the 4 types of IgG?

IgG is composed of four subclasses: IgG1, IgG2, IgG3, and IgG4 [1-9]. The structure, genetics, and function of the IgG subclasses are reviewed in this section. Detailed discussions of these topics as they apply to immunoglobulins in general are presented separately.

How many constant domains does IgG?

An intact IgG antibody consists of two heavy chains and two light chains. Each heavy chain contains four Ig domains, one “variable” domain, and three “constant” domains; whereas each light chain contains two Ig domains, one constant and one variable.

Which domains make up the heavy chain of an IgG antibody?

Heavy chains γ, α, and δ have a constant region composed of three tandem Ig domains – CH1, CH2, CH3 – and a hinge region for added flexibility. Heavy chains μ and ε have a constant region composed of four immunoglobulin domains.

What are IgG1 and IgG2?

IgG2 has a shorter hinge than IgG1, with 12 amino acid residues. The lower hinge region of IgG2 (actually encoded by the CH2 region) also has a one amino acid deletion (lacking one of the double Glycines found at position 235-6), resulting in IgG2 having the shortest hinge of all the IgG subclasses.

Whats is IgG subclasses?

The IgG class of antibodies is composed of four different subtypes of IgG molecules called the IgG subclasses. These are designated IgG1, IgG2, IgG3 and IgG4. Patients with persistently low levels of one or two IgG subclasses and a normal total IgG level have a selective IgG subclass deficiency.

What is the structure of IgG?

Structure. IgG antibodies are large globular proteins with a molecular weight of about 150 kDa made of four peptide chains. It contains two identical γ (gamma) heavy chains of about 50 kDa and two identical light chains of about 25 kDa, thus a tetrameric quaternary structure.

What does Fc region do?

The fragment crystallizable region (Fc region) is the tail region of an antibody that interacts with cell surface receptors called Fc receptors and some proteins of the complement system. This property allows antibodies to activate the immune system.

How many domains of IG are there?

The immunoglobulin domain, also known as the immunoglobulin fold, is a type of protein domain that consists of a 2-layer sandwich of 7-9 antiparallel β-strands arranged in two β-sheets with a Greek key topology, consisting of about 125 amino acids….Immunoglobulin domain.