ID   GRDH_PEPAC              Reviewed;         437 AA.
AC   O69407; Q9R4H0;
DT   26-SEP-2003, integrated into UniProtKB/Swiss-Prot.
DT   26-FEB-2008, sequence version 3.
DT   03-AUG-2022, entry version 64.
DE   RecName: Full=Betaine reductase complex component B subunit beta;
DE            EC=1.21.4.4;
DE   AltName: Full=Selenoprotein PB beta;
GN   Name=grdH;
OS   Peptoclostridium acidaminophilum (Eubacterium acidaminophilum).
OC   Bacteria; Firmicutes; Clostridia; Eubacteriales; Peptostreptococcaceae;
OC   Peptoclostridium.
OX   NCBI_TaxID=1731;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=ATCC 49065 / DSM 3953 / al-2;
RA   Sonntag D., Soehling B., Andreesen J.R.;
RL   Submitted (APR-1998) to the EMBL/GenBank/DDBJ databases.
RN   [2]
RP   PROTEIN SEQUENCE OF 1-40, AND CHARACTERIZATION.
RC   STRAIN=ATCC 49065 / DSM 3953 / al-2;
RX   PubMed=8529639; DOI=10.1111/j.1432-1033.1995.184_c.x;
RA   Meyer M., Granderath K., Andreesen J.R.;
RT   "Purification and characterization of protein PB of betaine reductase and
RT   its relationship to the corresponding proteins glycine reductase and
RT   sarcosine reductase from Eubacterium acidaminophilum.";
RL   Eur. J. Biochem. 234:184-191(1995).
CC   -!- FUNCTION: In the first step of betaine reductase, the substrate is
CC       bound to component PB via a Schiff base intermediate. Then the PB-
CC       activated substrate is nucleophilically attacked by the selenol anion
CC       of component PA to transform it to a carboxymethylated selenoether and
CC       the respective amine. By action of component PC, acetyl phosphate is
CC       formed, leaving component PA in its oxidized state. Finally component
CC       PA becomes reduced by the thioredoxin system to start a new catalytic
CC       cycle of reductive deamination.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=[thioredoxin]-disulfide + acetyl phosphate + H2O +
CC         trimethylamine = [thioredoxin]-dithiol + glycine betaine + H(+) +
CC         phosphate; Xref=Rhea:RHEA:11848, Rhea:RHEA-COMP:10698, Rhea:RHEA-
CC         COMP:10700, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:17750,
CC         ChEBI:CHEBI:22191, ChEBI:CHEBI:29950, ChEBI:CHEBI:43474,
CC         ChEBI:CHEBI:50058, ChEBI:CHEBI:58389; EC=1.21.4.4;
CC   -!- SUBUNIT: Heterotetramer of two alpha and two beta subunits. Component
CC       of the betaine reductase complex, together with components A and C. PB
CC       is substrate specific.
CC   -!- SIMILARITY: Belongs to the GrdB/GrdF/GrdH family. {ECO:0000305}.
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; Y17145; CAA76651.1; -; Genomic_DNA.
DR   PIR; S63506; S63506.
DR   PRIDE; O69407; -.
DR   GO; GO:0033795; F:betaine reductase activity; IEA:UniProtKB-EC.
DR   InterPro; IPR010187; Various_sel_PB.
DR   Pfam; PF07355; GRDB; 1.
DR   TIGRFAMs; TIGR01918; various_sel_PB; 1.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; Oxidoreductase; Selenocysteine.
FT   CHAIN           1..437
FT                   /note="Betaine reductase complex component B subunit beta"
FT                   /id="PRO_0000083844"
FT   ACT_SITE        349
FT   NON_STD         349
FT                   /note="Selenocysteine"
SQ   SEQUENCE   437 AA;  47613 MW;  DA8850D1EB99A4F9 CRC64;
     MKKAILYLNQ FFGQVGGEDK ADYEPEIING QVGAAMMLNG VLEGAEVTHT IICGDNFMGT
     YKDEAVSRIM GFLEDKEFDI FLAGPAFQAG RYGVACGEIC KVVKEKYNVP VVTSMHVENP
     GVQMFKKDMY VMIGGNNAGR MRQDMSAMAK VANKIIAGEK IGPADEEGFF PRGKRHQHWR
     EDGKPASERV VDMLLKKLSG EEFQTELPIP KSDRVEIAAP IKDLSKATIA VVTTGGIVPV
     DNPDRIQSAS ATRWGMYDVT GLERLEGGVY KTIHAGFDPA AADADPNVIV PLDALRAYEK
     EGKIGKVHEY FYSTVGTGTT EAEAARMAKE IVVKLKQGGV DGVIMTSTUG TCTRCGATMV
     KEIERAGFPI VQMCNLIPVA STVGANKIVP TISIPYPLGD PSTSKEQQWK LRYHRVGTAL
     DALTVDVQEQ TIFKVKI