MTNN_ECOSM
ID MTNN_ECOSM Reviewed; 232 AA.
AC B1LGW2;
DT 20-JAN-2009, integrated into UniProtKB/Swiss-Prot.
DT 29-APR-2008, sequence version 1.
DT 03-AUG-2022, entry version 78.
DE RecName: Full=5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=MTA/SAH nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=MTAN {ECO:0000255|HAMAP-Rule:MF_01684};
DE EC=3.2.2.9 {ECO:0000255|HAMAP-Rule:MF_01684};
DE AltName: Full=5'-deoxyadenosine nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=DOA nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=dAdo nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE AltName: Full=5'-methylthioadenosine nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=MTA nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE AltName: Full=S-adenosylhomocysteine nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=AdoHcy nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=SAH nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
DE Short=SRH nucleosidase {ECO:0000255|HAMAP-Rule:MF_01684};
GN Name=mtnN {ECO:0000255|HAMAP-Rule:MF_01684};
GN OrderedLocusNames=EcSMS35_0171;
OS Escherichia coli (strain SMS-3-5 / SECEC).
OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC Enterobacteriaceae; Escherichia.
OX NCBI_TaxID=439855;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=SMS-3-5 / SECEC;
RX PubMed=18708504; DOI=10.1128/jb.00661-08;
RA Fricke W.F., Wright M.S., Lindell A.H., Harkins D.M., Baker-Austin C.,
RA Ravel J., Stepanauskas R.;
RT "Insights into the environmental resistance gene pool from the genome
RT sequence of the multidrug-resistant environmental isolate Escherichia coli
RT SMS-3-5.";
RL J. Bacteriol. 190:6779-6794(2008).
CC -!- FUNCTION: Catalyzes the irreversible cleavage of the glycosidic bond in
CC both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine
CC (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-
CC methylthioribose and S-ribosylhomocysteine, respectively. Also cleaves
CC 5'-deoxyadenosine, a toxic by-product of radical S-adenosylmethionine
CC (SAM) enzymes, into 5-deoxyribose and adenine. Thus, is required for in
CC vivo function of the radical SAM enzymes biotin synthase and lipoic
CC acid synthase, that are inhibited by 5'-deoxyadenosine accumulation.
CC {ECO:0000255|HAMAP-Rule:MF_01684}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=H2O + S-adenosyl-L-homocysteine = adenine + S-(5-deoxy-D-
CC ribos-5-yl)-L-homocysteine; Xref=Rhea:RHEA:17805, ChEBI:CHEBI:15377,
CC ChEBI:CHEBI:16708, ChEBI:CHEBI:57856, ChEBI:CHEBI:58195; EC=3.2.2.9;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_01684};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=H2O + S-methyl-5'-thioadenosine = 5-(methylsulfanyl)-D-ribose
CC + adenine; Xref=Rhea:RHEA:13617, ChEBI:CHEBI:15377,
CC ChEBI:CHEBI:16708, ChEBI:CHEBI:17509, ChEBI:CHEBI:78440; EC=3.2.2.9;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_01684};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=5'-deoxyadenosine + H2O = 5-deoxy-D-ribose + adenine;
CC Xref=Rhea:RHEA:29859, ChEBI:CHEBI:15377, ChEBI:CHEBI:16708,
CC ChEBI:CHEBI:17319, ChEBI:CHEBI:149540; EC=3.2.2.9;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_01684};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:29860;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_01684};
CC -!- PATHWAY: Amino-acid biosynthesis; L-methionine biosynthesis via salvage
CC pathway; S-methyl-5-thio-alpha-D-ribose 1-phosphate from S-methyl-5'-
CC thioadenosine (hydrolase route): step 1/2. {ECO:0000255|HAMAP-
CC Rule:MF_01684}.
CC -!- SUBUNIT: Homodimer. {ECO:0000255|HAMAP-Rule:MF_01684}.
CC -!- SIMILARITY: Belongs to the PNP/UDP phosphorylase family. MtnN
CC subfamily. {ECO:0000255|HAMAP-Rule:MF_01684}.
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DR EMBL; CP000970; ACB17271.1; -; Genomic_DNA.
DR RefSeq; WP_000689844.1; NC_010498.1.
DR AlphaFoldDB; B1LGW2; -.
DR SMR; B1LGW2; -.
DR EnsemblBacteria; ACB17271; ACB17271; EcSMS35_0171.
DR GeneID; 66671551; -.
DR KEGG; ecm:EcSMS35_0171; -.
DR HOGENOM; CLU_031248_2_2_6; -.
DR OMA; DQFVHSK; -.
DR UniPathway; UPA00904; UER00871.
DR Proteomes; UP000007011; Chromosome.
DR GO; GO:0005737; C:cytoplasm; IEA:UniProt.
DR GO; GO:0008782; F:adenosylhomocysteine nucleosidase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0008930; F:methylthioadenosine nucleosidase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0019509; P:L-methionine salvage from methylthioadenosine; IEA:UniProtKB-UniPathway.
DR GO; GO:0019284; P:L-methionine salvage from S-adenosylmethionine; IEA:UniProtKB-UniRule.
DR GO; GO:0046124; P:purine deoxyribonucleoside catabolic process; IEA:UniProtKB-UniRule.
DR Gene3D; 3.40.50.1580; -; 1.
DR HAMAP; MF_01684; Salvage_MtnN; 1.
DR InterPro; IPR010049; MTA_SAH_Nsdase.
DR InterPro; IPR000845; Nucleoside_phosphorylase_d.
DR InterPro; IPR035994; Nucleoside_phosphorylase_sf.
DR Pfam; PF01048; PNP_UDP_1; 1.
DR SUPFAM; SSF53167; SSF53167; 1.
DR TIGRFAMs; TIGR01704; MTA/SAH-Nsdase; 1.
PE 3: Inferred from homology;
KW Amino-acid biosynthesis; Hydrolase; Methionine biosynthesis.
FT CHAIN 1..232
FT /note="5'-methylthioadenosine/S-adenosylhomocysteine
FT nucleosidase"
FT /id="PRO_0000359295"
FT ACT_SITE 12
FT /note="Proton acceptor"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_01684"
FT ACT_SITE 197
FT /note="Proton donor"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_01684"
FT BINDING 78
FT /ligand="substrate"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_01684"
FT BINDING 152
FT /ligand="substrate"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_01684"
FT BINDING 173..174
FT /ligand="substrate"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_01684"
SQ SEQUENCE 232 AA; 24354 MW; 9B1FF9BEC39D4F2C CRC64;
MKIGIIGAME EEVTLLRDKI ENRQTISLGG CEIYTGQLNG TEVALLKSGI GKVAAALGAT
LLLEHCKPDV IINTGSAGGL APTLKVGDIV VSDEARYHDA DVTAFGYEYG QLPGCPAGFK
ADDKLIAAAE ACIAELNLNA VRGLIVSGDA FINGSVGLAK IRHNFPQAIA VEMEATAIAH
VCHNFNVPFV VVRAISDVAD QQSHLSFDEF LAVAAKQSSL MVESLVQKLA HG
