CATH Classification

Domain Context

CATH Clusters

Superfamily Glutamine Phosphoribosylpyrophosphate, subunit 1, domain 1
Functional Family Proteasome subunit beta

Enzyme Information

3.4.25.1
Proteasome endopeptidase complex.
based on mapping to UniProt P28061
Cleavage of peptide bonds with very broad specificity.
-!- A 20-S protein composed of 28 subunits arranged in four rings of seven. -!- The outer rings are composed of alpha subunits, but the beta subunits forming the inner rings are responsible for peptidase activity. -!- In eukaryotic organisms there are up to seven different types of beta subunits, three of which may carry the N-terminal threonine residues that are the nucleophiles in catalysis, and show different specificities. -!- The molecule is barrel-shaped, and the active sites are on the inner surfaces. -!- Terminal apertures restrict access of substrates to the active sites. -!- Inhibited by mercurial reagents and some inhibitors of serine endopeptidases. -!- Belongs to peptidase family T1. -!- Formerly EC 3.4.22.21, EC 3.4.24.5 and EC 3.4.99.46.

UniProtKB Entries (1)

P25156
PSA_THEAC
Thermoplasma acidophilum DSM 1728
Proteasome subunit alpha

PDB Structure

PDB 6BDF
External Links
Method ELECTRON MICROSCOPY
Organism
Primary Citation
2.8 angstrom resolution reconstruction of the Thermoplasma acidophilum 20S proteasome using cryo-electron microscopy.
Campbell, M.G., Veesler, D., Cheng, A., Potter, C.S., Carragher, B.
Elife