What is a heavy chain in an antibody?
From Wikipedia, the free encyclopedia. A heavy-chain antibody is an antibody which consists only of two heavy chains and lacks the two light chains usually found in antibodies. In common antibodies, the antigen binding region consists of the variable domains of the heavy and light chains (VH and VL).
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.
How many amino acids are in IgG heavy chain?
There are five types of mammalian immunoglobulin heavy chain: γ, δ, α, μ and ε. They define classes of immunoglobulins: IgG, IgD, IgA, IgM and IgE, respectively. Heavy chains α and γ have approximately 450 amino acids. Heavy chains μ and ε have approximately 550 amino acids.
What is the function of the heavy chain?
Heavy chains may contain a transmembrane domain that allows for Ig to be expressed on the surface of B cells. They allow for antigen-specific binding and subsequent activation of B lymphocytes. Importantly, antigen binding by the antibody is not sufficient to induce a cellular activation signal.
What does the heavy chain do?
Which is the heaviest antibody?
IgM is the largest antibody, and it is the first antibody to appear in the response to initial exposure to an antigen.
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.
What are the VH and VL sequences?
The N-terminal domain at the tip of the arms of the “Y” on both the heavy and light chain are known to be variable in amino acid sequence composition and are thus called variable domains (VL and VH). The other domains are called constant for a similar reason (CL, CH1, CH2, CH3).
How many amino acids are in an antibody heavy chain?
110 amino acids
The variable region of each heavy chain is approximately 110 amino acids long and is composed of a single Ig domain.