Proteasome

A proteasome is a multi-protein complex that can digest other proteins into short polypeptides and amino acids in an ATP-driven reaction. The proteasome is hollow, providing an enclosed space for protein digestion.

For a description of the unit S, see Svedberg?. For A, see Angstrom.

26S proteasome

The 26S proteasome is used for the digestion of ubiquitin-marked proteins. It consists of a 19S and a 20S unit. The 20S unit consists of 14 α and 14 β subunits. It is about 150 A long and 115 A wide.