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HAMAP rule MF_01281

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General rule information [?]

Accession MF_01281
Dates 7-NOV-2007 (Created)
19-NOV-2022 (Last updated, Version 25)
Name MTA_SAH_deamin
Scope(s) Bacteria
Archaea
Template(s) Q9X034 (MTAD_THEMA); Q58936 (DADD_METJA); [ Recover all ]
Triggered by HAMAP; MF_01281 (Get profile general information and statistics)

Propagated annotation [?]

Identifier, protein and gene names [?]

case <OC:Methanobacteria> or <OC:Methanococci> or <OC:Methanomicrobia> or <OC:Methanopyri>
Identifier DADD
Protein name RecName: Full=5'-deoxyadenosine deaminase;
                 Short=5'-dA deaminase;
                 EC=3.5.4.41;
AltName: Full=5'-methylthioadenosine deaminase;
                 Short=MTA deaminase;
                 EC=3.5.4.31;
AltName: Full=Adenosine deaminase;
                 EC=3.5.4.4;
AltName: Full=S-adenosylhomocysteine deaminase;
                 Short=SAH deaminase;
                 EC=3.5.4.28;
Gene name Name=dadD;
else
Identifier MTAD
Protein name RecName: Full=5-methylthioadenosine/S-adenosylhomocysteine deaminase;
                 Short=MTA/SAH deaminase;
                 EC=3.5.4.28;
                 EC=3.5.4.31;
Gene name Name=mtaD;
end case

Comments [?]

case <OC:Methanobacteria> or <OC:Methanococci> or <OC:Methanomicrobia> or <OC:Methanopyri>
FUNCTIONCatalyzes the deamination of three SAM-derived enzymatic products, namely 5'-deoxyadenosine, S-adenosyl-L-homocysteine, and 5'- methylthioadenosine, to produce the inosine analogs. Can also deaminate adenosine. The preferred substrate for this enzyme is 5'- deoxyadenosine, but all these substrates are efficiently deaminated. Likely functions in a S-adenosyl-L-methionine (SAM) recycling pathway from S-adenosyl-L-homocysteine (SAH) produced from SAM-dependent methylation reactions. May also be involved in the recycling of 5'- deoxyadenosine, whereupon the 5'-deoxyribose moiety of 5'-deoxyinosine is further metabolized to deoxyhexoses used for the biosynthesis of aromatic amino acids in methanogens.
CATALYTIC ACTIVITY Reaction=5'-deoxyadenosine + H(+) + H2O = 5'-deoxyinosine + NH4(+); Xref=Rhea:RHEA:42892, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:17319, ChEBI:CHEBI:28938, ChEBI:CHEBI:82775; EC=3.5.4.41; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:42893;
CATALYTIC ACTIVITY Reaction=H(+) + H2O + S-adenosyl-L-homocysteine = NH4(+) + S-inosyl-L- homocysteine; Xref=Rhea:RHEA:20716, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:28938, ChEBI:CHEBI:57856, ChEBI:CHEBI:57985; EC=3.5.4.28; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:20717;
CATALYTIC ACTIVITY Reaction=H(+) + H2O + S-methyl-5'-thioadenosine = NH4(+) + S-methyl-5'- thioinosine; Xref=Rhea:RHEA:25025, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:17509, ChEBI:CHEBI:28938, ChEBI:CHEBI:48595; EC=3.5.4.31; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:25026;
CATALYTIC ACTIVITY Reaction=adenosine + H(+) + H2O = inosine + NH4(+); Xref=Rhea:RHEA:24408, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:16335, ChEBI:CHEBI:17596, ChEBI:CHEBI:28938; EC=3.5.4.4; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:24409;
PATHWAYAmino-acid biosynthesis; S-adenosyl-L-methionine biosynthesis.
SUBUNITHomotetramer.
MISCELLANEOUSSAH is a product of SAM methyltransferases and is known to be a feedback inhibitor of these enzymes. As a result of this inhibition, organisms have evolved efficient enzymes to metabolize SAH via different pathways. The pathway found in methanogens differs from the canonical pathway, it uses the deamination of S-adenosyl-L- homocysteine to form S-inosyl-L-homocysteine for the regeneration of SAM from S-adenosyl-L-homocysteine. 5'-deoxyadenosine is a radical SAM enzyme reaction product which strongly inhibits radical SAM enzymes. A pathway for removing this product must be present in methanogens where the MTA/SAH nucleosidase which normally metabolizes this compound is absent.
else
FUNCTIONCatalyzes the deamination of 5-methylthioadenosine and S- adenosyl-L-homocysteine into 5-methylthioinosine and S-inosyl-L- homocysteine, respectively. Is also able to deaminate adenosine.
CATALYTIC ACTIVITY Reaction=H(+) + H2O + S-adenosyl-L-homocysteine = NH4(+) + S-inosyl-L- homocysteine; Xref=Rhea:RHEA:20716, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:28938, ChEBI:CHEBI:57856, ChEBI:CHEBI:57985; EC=3.5.4.28;
CATALYTIC ACTIVITY Reaction=H(+) + H2O + S-methyl-5'-thioadenosine = NH4(+) + S-methyl-5'- thioinosine; Xref=Rhea:RHEA:25025, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:17509, ChEBI:CHEBI:28938, ChEBI:CHEBI:48595; EC=3.5.4.31;
end case
COFACTOR Name=Zn(2+); Xref=ChEBI:CHEBI:29105; Note=Binds 1 zinc ion per subunit.;
SIMILARITYBelongs to the metallo-dependent hydrolases superfamily. MTA/SAH deaminase family.

Keywords [?]


Gene Ontology [?]

case <OCellular component:Methanobacteria> or <OC:Methanococci> or <OC:Methanomicrobia> or <OC:Methanopyri>
GO:0090613; Molecular function:5'-deoxyadenosine deaminase activity
GO:0004000; Molecular function:adenosine deaminase activity
else; https://www.ebi.ac.uk/QuickGO/term/else
GO:0050270; Molecular function:S-adenosylhomocysteine deaminase activity
GO:0090614; Molecular function:5'-methylthioadenosine deaminase activity
end case

Cross-references [?]

Pfam PF01979; Amidohydro_1; 1;

Features [?]

From: MTAD_THEMA (Q9X034)
Key From To Description Tag Condition FTGroup
BINDING 55 55 /ligand="Zn(2+)"
/ligand_id="ChEBI:CHEBI:29105"
H
BINDING 57 57 /ligand="Zn(2+)"
/ligand_id="ChEBI:CHEBI:29105"
H
BINDING 200 200 /ligand="Zn(2+)"
/ligand_id="ChEBI:CHEBI:29105"
H
BINDING 279 279 /ligand="Zn(2+)"
/ligand_id="ChEBI:CHEBI:29105"
D
BINDING 84 84 /ligand="substrate" E
BINDING 136 136 /ligand="substrate" R
BINDING 148 148 /ligand="substrate" R
BINDING 173 173 /ligand="substrate" H
BINDING 203 203 /ligand="substrate" E
BINDING 279 279 /ligand="substrate" D

Additional information [?]

Size range 406-449 amino acids
Related rules None
Fusion Nter: None Cter: None



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