MTNN_SALPB
ID MTNN_SALPB Reviewed; 232 AA.
AC A9N0Q5;
DT 20-JAN-2009, integrated into UniProtKB/Swiss-Prot.
DT 05-FEB-2008, sequence version 1.
DT 03-AUG-2022, entry version 75.
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}; OrderedLocusNames=SPAB_00265;
OS Salmonella paratyphi B (strain ATCC BAA-1250 / SPB7).
OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC Enterobacteriaceae; Salmonella.
OX NCBI_TaxID=1016998;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC BAA-1250 / SPB7;
RG The Salmonella enterica serovar Paratyphi B Genome Sequencing Project;
RA McClelland M., Sanderson E.K., Porwollik S., Spieth J., Clifton W.S.,
RA Fulton R., Cordes M., Wollam A., Shah N., Pepin K., Bhonagiri V., Nash W.,
RA Johnson M., Thiruvilangam P., Wilson R.;
RL Submitted (NOV-2007) to the EMBL/GenBank/DDBJ databases.
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; CP000886; ABX65707.1; -; Genomic_DNA.
DR RefSeq; WP_000689821.1; NC_010102.1.
DR AlphaFoldDB; A9N0Q5; -.
DR SMR; A9N0Q5; -.
DR KEGG; spq:SPAB_00265; -.
DR PATRIC; fig|1016998.12.peg.257; -.
DR HOGENOM; CLU_031248_2_2_6; -.
DR OMA; DQFVHSK; -.
DR BioCyc; SENT1016998:SPAB_RS01075-MON; -.
DR UniPathway; UPA00904; UER00871.
DR Proteomes; UP000008556; 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_0000359336"
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; 24446 MW; 90E2638E702B9B26 CRC64;
MKIGIIGAME EEVTLLRDKI DNRQTITLGG CEIYTGQLNG TEVALLKSGI GKVAAALGAT
LLLEHCKPDV IINTGSAGGL ASTLKVGDIV VSDEARYHDA DVTAFGYEYG QLPGCPAGFK
ADDKLIAAAE SCIRELNLNA VRGLIVSGDA FINGSVGLAK IRHNFPDAVA VEMEATAIAH
VCHNFNVPFV VVRAISDVAD QQSHLSFDEF LAVAAKQSTL MVETLVQKLA HG
