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 (3)

Q38BM8
Q38BM8_TRYB2
Trypanosoma brucei brucei TREU927
Proteasome activator protein PA26
Q58576
PAN_METJA
Methanocaldococcus jannaschii DSM 2661
Proteasome-activating nucleotidase
P28061
PSB_THEAC
Thermoplasma acidophilum DSM 1728
Proteasome subunit beta

PDB Structure

PDB 3IPM
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Interactions of PAN's C-termini with archaeal 20S proteasome and implications for the eukaryotic proteasome-ATPase interactions.
Yu, Y., Smith, D.M., Kim, H.M., Rodriguez, V., Goldberg, A.L., Cheng, Y.
Embo J.