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HAMAP rule MF_01684

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General rule information [?]

Accession MF_01684
Dates 19-NOV-2008 (Created)
14-MAY-2022 (Last updated, Version 22)
Name Salvage_MtnN
Scope
Bacteria
Templates P0AF12 (MTNN_ECOLI); O32028 (MTNN_BACSU); Q9R4A1 (MTNN_KLEPN): [Recover all]
Triggered by

Propagated annotation [?]


Identifier, protein and gene names [?]

Identifier
MTNN
Protein name
RecName: Full=5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase;
Short=MTA/SAH nucleosidase;
Short=MTAN;
EC 3.2.2.9;
AltName: Full=5'-deoxyadenosine nucleosidase;
Short=DOA nucleosidase;
Short=dAdo nucleosidase;
AltName: Full=5'-methylthioadenosine nucleosidase;
Short=MTA nucleosidase;
AltName: Full=S-adenosylhomocysteine nucleosidase;
Short=AdoHcy nucleosidase;
Short=SAH nucleosidase;
Short=SRH nucleosidase;
Gene name
mtnN

Comments [?]

case <OC:Enterobacterales>
Function Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. Also cleaves 5'-deoxyadenosine, a toxic by-product of radical S-adenosylmethionine (SAM) enzymes, into 5-deoxyribose and adenine. Thus, is required for in vivo function of the radical SAM enzymes biotin synthase and lipoic acid synthase, that are inhibited by 5'-deoxyadenosine accumulation.
else
Function Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. Also cleaves 5'-deoxyadenosine, a toxic by-product of radical S-adenosylmethionine (SAM) enzymes, into 5-deoxyribose and adenine.
end case
Catalytic activity RHEA:17805: H2O + S-adenosyl-L-homocysteine = adenine + S-(5-deoxy-D-ribos-5-yl)-L-homocysteine
EC 3.2.2.9
RHEA:13617: H2O + S-methyl-5'-thioadenosine = 5-(methylsulfanyl)-D-ribose + adenine
EC 3.2.2.9
RHEA:29859: 5'-deoxyadenosine + H2O = 5-deoxy-D-ribose + adenine
EC 3.2.2.9
PhysiologicalDirection=left-to-right (RHEA:29860)
Pathway Amino-acid biosynthesis; L-methionine biosynthesis via salvage pathway; S-methyl-5-thio-alpha-D-ribose 1-phosphate from S-methyl-5'-thioadenosine (hydrolase route): step 1/2.
case <OC:Enterobacterales>
Subunit Homodimer.
end case
Similarity Belongs to the PNP/UDP phosphorylase family. MtnN subfamily.

Keywords [?]

Amino-acid biosynthesis
Hydrolase
Methionine biosynthesis

Gene Ontology [?]

GO:0008782; Molecular function: adenosylhomocysteine nucleosidase activity.
GO:0008930; Molecular function: methylthioadenosine nucleosidase activity.
GO:0019284; Biological process: L-methionine salvage from S-adenosylmethionine.
case <OC:Enterobacterales>
GO:0046124; Biological process: purine deoxyribonucleoside catabolic process.
end case

Cross-references [?]

Pfam PF01048; PNP_UDP_1; 1;
TIGRFAMs TIGR01704; MTA/SAH-Nsdase; 1;

Features [?]

From: MTNN_ECOLI (P0AF12)
Key     From     To       Description   Tag   Condition   FTGroup
BINDING     173     174       /ligand="substrate     M-[ED]  
ACT_SITE     12     12       Proton acceptor     E  
ACT_SITE     197     197       Proton donor     D  
BINDING     78     78       /ligand="substrate     [GA]  
BINDING     152     152       /ligand="substrate     [IVML]  

Additional information [?]

Size range 221-251 amino acids
Related rules None
Fusion None


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