Envelope glycoprotein GP120

• UniProt: P04578

Gp120 is a glycoprotein, which is located on the surface of HIV particles. The number 120 in his name means that its molecular mass is 120 kDa.

The protein consists of an outer and an inner portion, and a connecting bridge. It is composed of 500 amino acids. It forms a sort of cap over the end of gp41 and thus represents a gp120/gp41-Untereinheit Without qualifying this cap could human antibodies by they would attach themselves to the end of gp41 detect the virus. When the virus now attaches itself to a human cell, gp120 changes its configuration abruptly and puts gp41 free. This then attaches itself to the cell.

The HIV virus mutates frequently and is therefore not recognized by the immune system. But there is one area that needs to stay the same forever, so that the virus can bind to human cells and infect them. The glycoprotein gp120 is connected just as gp41 to the cell membrane by non- covalent bonds. Both are descendants of the cleaved gp160 protein. This each cell infected with a CD4 receptor, in particular the T helper cell by themselves attached to it. This compound is mainly ionic, although van der Waals forces and hydrogen bonds play a role.