ID   RIHB_SHISS              Reviewed;         313 AA.
AC   Q3Z044;
DT   10-JAN-2006, integrated into UniProtKB/Swiss-Prot.
DT   27-SEP-2005, sequence version 1.
DT   03-AUG-2022, entry version 92.
DE   RecName: Full=Pyrimidine-specific ribonucleoside hydrolase RihB {ECO:0000255|HAMAP-Rule:MF_01433};
DE            EC=3.2.2.8 {ECO:0000255|HAMAP-Rule:MF_01433};
DE   AltName: Full=Cytidine/uridine-specific hydrolase {ECO:0000255|HAMAP-Rule:MF_01433};
GN   Name=rihB {ECO:0000255|HAMAP-Rule:MF_01433}; OrderedLocusNames=SSON_2218;
OS   Shigella sonnei (strain Ss046).
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC   Enterobacteriaceae; Shigella.
OX   NCBI_TaxID=300269;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=Ss046;
RX   PubMed=16275786; DOI=10.1093/nar/gki954;
RA   Yang F., Yang J., Zhang X., Chen L., Jiang Y., Yan Y., Tang X., Wang J.,
RA   Xiong Z., Dong J., Xue Y., Zhu Y., Xu X., Sun L., Chen S., Nie H., Peng J.,
RA   Xu J., Wang Y., Yuan Z., Wen Y., Yao Z., Shen Y., Qiang B., Hou Y., Yu J.,
RA   Jin Q.;
RT   "Genome dynamics and diversity of Shigella species, the etiologic agents of
RT   bacillary dysentery.";
RL   Nucleic Acids Res. 33:6445-6458(2005).
CC   -!- FUNCTION: Hydrolyzes cytidine or uridine to ribose and cytosine or
CC       uracil, respectively. Has a clear preference for cytidine over uridine.
CC       Strictly specific for ribonucleosides. {ECO:0000255|HAMAP-
CC       Rule:MF_01433}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=a pyrimidine ribonucleoside + H2O = a pyrimidine nucleobase +
CC         D-ribose; Xref=Rhea:RHEA:56816, ChEBI:CHEBI:15377, ChEBI:CHEBI:26432,
CC         ChEBI:CHEBI:47013, ChEBI:CHEBI:141014; EC=3.2.2.8;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_01433};
CC   -!- COFACTOR:
CC       Name=Ca(2+); Xref=ChEBI:CHEBI:29108;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_01433};
CC       Note=Binds 1 Ca(2+) ion per monomer. {ECO:0000255|HAMAP-Rule:MF_01433};
CC   -!- SUBUNIT: Homotetramer. {ECO:0000255|HAMAP-Rule:MF_01433}.
CC   -!- SIMILARITY: Belongs to the IUNH family. RihB subfamily.
CC       {ECO:0000255|HAMAP-Rule:MF_01433}.
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DR   EMBL; CP000038; AAZ88868.1; -; Genomic_DNA.
DR   AlphaFoldDB; Q3Z044; -.
DR   SMR; Q3Z044; -.
DR   EnsemblBacteria; AAZ88868; AAZ88868; SSON_2218.
DR   KEGG; ssn:SSON_2218; -.
DR   HOGENOM; CLU_036838_2_0_6; -.
DR   OMA; REKAHEW; -.
DR   Proteomes; UP000002529; Chromosome.
DR   GO; GO:0005509; F:calcium ion binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0045437; F:uridine nucleosidase activity; IEA:UniProt.
DR   GO; GO:0006206; P:pyrimidine nucleobase metabolic process; IEA:UniProtKB-UniRule.
DR   GO; GO:0046133; P:pyrimidine ribonucleoside catabolic process; IEA:InterPro.
DR   Gene3D; 3.90.245.10; -; 1.
DR   HAMAP; MF_01433; Pyrim_hydro_RihB; 1.
DR   InterPro; IPR015910; I/U_nuclsd_hydro_CS.
DR   InterPro; IPR001910; Inosine/uridine_hydrolase_dom.
DR   InterPro; IPR023186; IUNH.
DR   InterPro; IPR022977; Pyrim_hydro_RihB.
DR   InterPro; IPR036452; Ribo_hydro-like.
DR   PANTHER; PTHR12304; PTHR12304; 1.
DR   Pfam; PF01156; IU_nuc_hydro; 1.
DR   SUPFAM; SSF53590; SSF53590; 1.
DR   PROSITE; PS01247; IUNH; 1.
PE   3: Inferred from homology;
KW   Calcium; Glycosidase; Hydrolase; Metal-binding.
FT   CHAIN           1..313
FT                   /note="Pyrimidine-specific ribonucleoside hydrolase RihB"
FT                   /id="PRO_0000206830"
FT   ACT_SITE        11
FT                   /note="Proton acceptor"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         11
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         16
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         124
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         227
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         239
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
FT   BINDING         240
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01433"
SQ   SEQUENCE   313 AA;  33766 MW;  5A2AA913C4EC5199 CRC64;
     MEKRKIILDC DPGHDDAIAI MMAAKHPAID LLGITIVAGN QTLDKTLING LNVCQKLEIN
     VPVYAGMPQP IMRQQIVADN IHGETGLDGP VFEPLTRQAE STHAVKYIID TLMASDGDIT
     LVPVGPLSNI AVAMRMQPAI LPKIREIVLM GGAYGTGNFT PSAEFNIFAD PEAARVVFTS
     GVPLVMMGLD LTNQTVCTPD VIARMERAGG PAGEMFSDIM NFTLKTQFEN YGLAGGPVHD
     ATCIGYLINP DGIKTQEMYV EVDVNSGPCY GRTVCDELGV LGKPANTKVG ITIDTDWFWG
     LVEECVRGYI KTH