ID   PSB_METST               Reviewed;         205 AA.
AC   Q2NI68;
DT   10-AUG-2010, integrated into UniProtKB/Swiss-Prot.
DT   07-FEB-2006, sequence version 1.
DT   25-MAY-2022, entry version 91.
DE   RecName: Full=Proteasome subunit beta {ECO:0000255|HAMAP-Rule:MF_02113};
DE            EC=3.4.25.1 {ECO:0000255|HAMAP-Rule:MF_02113};
DE   AltName: Full=20S proteasome beta subunit {ECO:0000255|HAMAP-Rule:MF_02113};
DE   AltName: Full=Proteasome core protein PsmB {ECO:0000255|HAMAP-Rule:MF_02113};
DE   Flags: Precursor;
GN   Name=psmB {ECO:0000255|HAMAP-Rule:MF_02113}; OrderedLocusNames=Msp_0282;
OS   Methanosphaera stadtmanae (strain ATCC 43021 / DSM 3091 / JCM 11832 /
OS   MCB-3).
OC   Archaea; Euryarchaeota; Methanomada group; Methanobacteria;
OC   Methanobacteriales; Methanobacteriaceae; Methanosphaera.
OX   NCBI_TaxID=339860;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 43021 / DSM 3091 / JCM 11832 / MCB-3;
RX   PubMed=16385054; DOI=10.1128/jb.188.2.642-658.2006;
RA   Fricke W.F., Seedorf H., Henne A., Kruer M., Liesegang H., Hedderich R.,
RA   Gottschalk G., Thauer R.K.;
RT   "The genome sequence of Methanosphaera stadtmanae reveals why this human
RT   intestinal archaeon is restricted to methanol and H2 for methane formation
RT   and ATP synthesis.";
RL   J. Bacteriol. 188:642-658(2006).
CC   -!- FUNCTION: Component of the proteasome core, a large protease complex
CC       with broad specificity involved in protein degradation.
CC       {ECO:0000255|HAMAP-Rule:MF_02113}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Cleavage of peptide bonds with very broad specificity.;
CC         EC=3.4.25.1; Evidence={ECO:0000255|HAMAP-Rule:MF_02113};
CC   -!- ACTIVITY REGULATION: The formation of the proteasomal ATPase PAN-20S
CC       proteasome complex, via the docking of the C-termini of PAN into the
CC       intersubunit pockets in the alpha-rings, triggers opening of the gate
CC       for substrate entry. Interconversion between the open-gate and close-
CC       gate conformations leads to a dynamic regulation of the 20S proteasome
CC       proteolysis activity. {ECO:0000255|HAMAP-Rule:MF_02113}.
CC   -!- SUBUNIT: The 20S proteasome core is composed of 14 alpha and 14 beta
CC       subunits that assemble into four stacked heptameric rings, resulting in
CC       a barrel-shaped structure. The two inner rings, each composed of seven
CC       catalytic beta subunits, are sandwiched by two outer rings, each
CC       composed of seven alpha subunits. The catalytic chamber with the active
CC       sites is on the inside of the barrel. Has a gated structure, the ends
CC       of the cylinder being occluded by the N-termini of the alpha-subunits.
CC       Is capped at one or both ends by the proteasome regulatory ATPase, PAN.
CC       {ECO:0000255|HAMAP-Rule:MF_02113}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_02113}.
CC   -!- SIMILARITY: Belongs to the peptidase T1B family. {ECO:0000255|HAMAP-
CC       Rule:MF_02113}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; CP000102; ABC56692.1; -; Genomic_DNA.
DR   RefSeq; WP_011405892.1; NC_007681.1.
DR   AlphaFoldDB; Q2NI68; -.
DR   SMR; Q2NI68; -.
DR   STRING; 339860.Msp_0282; -.
DR   MEROPS; T01.002; -.
DR   EnsemblBacteria; ABC56692; ABC56692; Msp_0282.
DR   GeneID; 41324855; -.
DR   KEGG; mst:Msp_0282; -.
DR   eggNOG; arCOG00970; Archaea.
DR   HOGENOM; CLU_035750_7_2_2; -.
DR   OMA; VDKTGPH; -.
DR   OrthoDB; 89767at2157; -.
DR   Proteomes; UP000001931; Chromosome.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0019774; C:proteasome core complex, beta-subunit complex; IEA:UniProtKB-UniRule.
DR   GO; GO:0004298; F:threonine-type endopeptidase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0010498; P:proteasomal protein catabolic process; IEA:UniProtKB-UniRule.
DR   CDD; cd03764; proteasome_beta_archeal; 1.
DR   Gene3D; 3.60.20.10; -; 1.
DR   HAMAP; MF_02113_A; Proteasome_B_A; 1.
DR   InterPro; IPR029055; Ntn_hydrolases_N.
DR   InterPro; IPR019983; Pept_T1A_Psome_bsu_arc.
DR   InterPro; IPR000243; Pept_T1A_subB.
DR   InterPro; IPR001353; Proteasome_sua/b.
DR   InterPro; IPR023333; Proteasome_suB-type.
DR   Pfam; PF00227; Proteasome; 1.
DR   PRINTS; PR00141; PROTEASOME.
DR   SUPFAM; SSF56235; SSF56235; 1.
DR   TIGRFAMs; TIGR03634; arc_protsome_B; 1.
DR   PROSITE; PS51476; PROTEASOME_BETA_2; 1.
PE   3: Inferred from homology;
KW   Autocatalytic cleavage; Cytoplasm; Hydrolase; Protease; Proteasome;
KW   Reference proteome; Threonine protease; Zymogen.
FT   PROPEP          1..9
FT                   /note="Removed in mature form; by autocatalysis"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_02113"
FT                   /id="PRO_0000397374"
FT   CHAIN           10..205
FT                   /note="Proteasome subunit beta"
FT                   /id="PRO_0000397375"
FT   ACT_SITE        10
FT                   /note="Nucleophile"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_02113"
SQ   SEQUENCE   205 AA;  22360 MW;  BD665B8926A37A62 CRC64;
     MNQTENMEGT TTVGFVCTDG VVLATETRAT MGSLVANKNA DKLFQIDDKI GATIAGTVSH
     AQSLMDILKA EISLYKLRNE KDMSIDALAV LTSNILKSRP YYVQTILAGV DKDGAKLYTL
     DPSGSYIPDT FTSTGSGSPY AFGVLEDRYN EDITTEEGKK IAIKAITSAM ERDVYSGNNY
     RLGVITKDGM KIYTKEEIAQ IKKQL