CATH Classification

Domain Context

CATH Clusters

Superfamily Glutamine Phosphoribosylpyrophosphate, subunit 1, domain 1
Functional Family Proteasome subunit alpha type-3

Enzyme Information

3.4.25.1
Proteasome endopeptidase complex.
based on mapping to UniProt P23638
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)

P22141
PSB4_YEAST
Saccharomyces cerevisiae S288C
Proteasome subunit beta type-4

PDB Structure

PDB 4R02
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
alpha-Keto Phenylamides as P1'-Extended Proteasome Inhibitors.
Voss, C., Scholz, C., Knorr, S., Beck, P., Stein, M.L., Zall, A., Kuckelkorn, U., Kloetzel, P.M., Groll, M., Hamacher, K., Schmidt, B.
Chemmedchem