Ribosomal protein

A large ribosomal subunit (PDB: 1FFK​).

A small ribosomal subunit (PDB: 1FKA​).

The two ribosomal subunits. Proteins are shown in blue and the RNA chains in brown and yellow.

A ribosomal protein (r-protein or rProtein^[1][2][3]) is any of the proteins that, in conjunction with rRNA, make up the ribosomal subunits involved in the cellular process of translation. E. coli, other bacteria and Archaea have a 30S small subunit and a 50S large subunit, whereas humans and yeasts have a 40S small subunit and a 60S large subunit.^[4] Equivalent subunits are frequently numbered differently between bacteria, Archaea, yeasts and humans.^[5]

A large part of the knowledge about these organic molecules has come from the study of E. coli ribosomes. All ribosomal proteins have been isolated and many specific antibodies have been produced. These, together with electronic microscopy and the use of certain reactives, have allowed for the determination of the topography of the proteins in the ribosome. More recently, a near-complete (near)atomic picture of the ribosomal proteins is emerging from the latest high-resolution cryo-EM data (including PDB: 5AFI​).