The major building block of immunoglobulins is the immunoglobulin domain. Here we focus on a single Ig domain: the constant Ig domain of the light chain, C_L.

Each Ig domain is shaped like a rounded brick about 15 x 20 x 50 Å.

The core of each Ig domain consists of two beta sheets, made of 3 and 4 beta strands.

Cartoon.

Rainbow: N terminus to C terminus

Disulfide bond. Apply this button to any backbone or cartoon image.

Hydrophobic core (front half cut away).
    Backbone
    Polar, Charged sidechains
    Hydrophobic sidechains
    Disulfide.