CATH Classification

Domain Context

CATH Clusters

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

Enzyme Information

3.4.25.1
Proteasome endopeptidase complex.
based on mapping to UniProt P20618
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.
3.4.25.1
Proteasome endopeptidase complex.
based on mapping to UniProt P23724
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 (2)

P28062
PSB8_HUMAN
Homo sapiens
Proteasome subunit beta type-8
P38624
PSB1_YEAST
Saccharomyces cerevisiae S288C
Proteasome subunit beta type-1

PDB Structure

PDB 5L5E
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
A humanized yeast proteasome identifies unique binding modes of inhibitors for the immunosubunit beta 5i.
Huber, E.M., Heinemeyer, W., de Bruin, G., Overkleeft, H.S., Groll, M.
EMBO J.