Integral membrane proteins
Integral membrane proteins are those which are embedded directly into the phospholipid bilayer cell membrane. Although all highly specific, they can be placed into one of three categories:
1. Cytosolic Integral Membrane Proteins
Proteins which are embedded only into the inner leaflet of the phospholipid bilayer membrane.
2. Cell Surface Proteins
Proteins which are embedded only into the outer leaflet of the phospholipid bilayer membrane.
3. Transmembrane Proteins
Proteins which span the entire phospholipid bilayer membrane, from the cytosol to the exterior of the cell.
All integral membrane proteins can be released from the cell membrane by the use of a detergent.