AC MF_01281; DC Protein; auto TR HAMAP; MF_01281; -; 1; level=0 XX Names: MTA_SAH_deamin XX case or or or ID DADD DE RecName: Full=5'-deoxyadenosine deaminase; DE Short=5'-dA deaminase; DE EC=3.5.4.41; DE AltName: Full=5'-methylthioadenosine deaminase; DE Short=MTA deaminase; DE EC=3.5.4.31; DE AltName: Full=Adenosine deaminase; DE EC=3.5.4.4; DE AltName: Full=S-adenosylhomocysteine deaminase; DE Short=SAH deaminase; DE EC=3.5.4.28; GN Name=dadD; else ID MTAD DE RecName: Full=5-methylthioadenosine/S-adenosylhomocysteine deaminase; DE Short=MTA/SAH deaminase; DE EC=3.5.4.28; DE EC=3.5.4.31; GN Name=mtaD; end case XX case or or or CC -!- FUNCTION: Catalyzes the deamination of three SAM-derived enzymatic CC products, namely 5'-deoxyadenosine, S-adenosyl-L-homocysteine, and 5'- CC methylthioadenosine, to produce the inosine analogs. Can also deaminate CC adenosine. The preferred substrate for this enzyme is 5'- CC deoxyadenosine, but all these substrates are efficiently deaminated. CC Likely functions in a S-adenosyl-L-methionine (SAM) recycling pathway CC from S-adenosyl-L-homocysteine (SAH) produced from SAM-dependent CC methylation reactions. May also be involved in the recycling of 5'- CC deoxyadenosine, whereupon the 5'-deoxyribose moiety of 5'-deoxyinosine CC is further metabolized to deoxyhexoses used for the biosynthesis of CC aromatic amino acids in methanogens. CC -!- CATALYTIC ACTIVITY: CC Reaction=5'-deoxyadenosine + H(+) + H2O = 5'-deoxyinosine + NH4(+); CC Xref=Rhea:RHEA:42892, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, CC ChEBI:CHEBI:17319, ChEBI:CHEBI:28938, ChEBI:CHEBI:82775; EC=3.5.4.41; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:42893; CC -!- CATALYTIC ACTIVITY: CC Reaction=H(+) + H2O + S-adenosyl-L-homocysteine = NH4(+) + S-inosyl-L- CC homocysteine; Xref=Rhea:RHEA:20716, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:28938, ChEBI:CHEBI:57856, CC ChEBI:CHEBI:57985; EC=3.5.4.28; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:20717; CC -!- CATALYTIC ACTIVITY: CC Reaction=H(+) + H2O + S-methyl-5'-thioadenosine = NH4(+) + S-methyl-5'- CC thioinosine; Xref=Rhea:RHEA:25025, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:17509, ChEBI:CHEBI:28938, CC ChEBI:CHEBI:48595; EC=3.5.4.31; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:25026; CC -!- CATALYTIC ACTIVITY: CC Reaction=adenosine + H(+) + H2O = inosine + NH4(+); CC Xref=Rhea:RHEA:24408, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, CC ChEBI:CHEBI:16335, ChEBI:CHEBI:17596, ChEBI:CHEBI:28938; EC=3.5.4.4; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:24409; CC -!- PATHWAY: Amino-acid biosynthesis; S-adenosyl-L-methionine biosynthesis. CC -!- SUBUNIT: Homotetramer. CC -!- MISCELLANEOUS: SAH is a product of SAM methyltransferases and is known CC to be a feedback inhibitor of these enzymes. As a result of this CC inhibition, organisms have evolved efficient enzymes to metabolize SAH CC via different pathways. The pathway found in methanogens differs from CC the canonical pathway, it uses the deamination of S-adenosyl-L- CC homocysteine to form S-inosyl-L-homocysteine for the regeneration of CC SAM from S-adenosyl-L-homocysteine. 5'-deoxyadenosine is a radical SAM CC enzyme reaction product which strongly inhibits radical SAM enzymes. A CC pathway for removing this product must be present in methanogens where CC the MTA/SAH nucleosidase which normally metabolizes this compound is CC absent. else CC -!- FUNCTION: Catalyzes the deamination of 5-methylthioadenosine and S- CC adenosyl-L-homocysteine into 5-methylthioinosine and S-inosyl-L- CC homocysteine, respectively. Is also able to deaminate adenosine. CC -!- CATALYTIC ACTIVITY: CC Reaction=H(+) + H2O + S-adenosyl-L-homocysteine = NH4(+) + S-inosyl-L- CC homocysteine; Xref=Rhea:RHEA:20716, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:28938, ChEBI:CHEBI:57856, CC ChEBI:CHEBI:57985; EC=3.5.4.28; CC -!- CATALYTIC ACTIVITY: CC Reaction=H(+) + H2O + S-methyl-5'-thioadenosine = NH4(+) + S-methyl-5'- CC thioinosine; Xref=Rhea:RHEA:25025, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:17509, ChEBI:CHEBI:28938, CC ChEBI:CHEBI:48595; EC=3.5.4.31; end case CC -!- COFACTOR: CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105; CC Note=Binds 1 zinc ion per subunit.; CC -!- SIMILARITY: Belongs to the metallo-dependent hydrolases superfamily. CC MTA/SAH deaminase family. XX DR Pfam; PF01979; Amidohydro_1; 1; trigger=no XX KW Hydrolase KW Metal-binding KW Zinc XX case or or or GO GO:0090613; F:5'-deoxyadenosine deaminase activity GO GO:0004000; F:adenosine deaminase activity else GO GO:0050270; F:S-adenosylhomocysteine deaminase activity GO GO:0090614; F:5'-methylthioadenosine deaminase activity end case XX FT From: MTAD_THEMA (Q9X034) FT BINDING 55 FT /ligand="Zn(2+)" FT /ligand_id="ChEBI:CHEBI:29105" FT Condition: H FT BINDING 57 FT /ligand="Zn(2+)" FT /ligand_id="ChEBI:CHEBI:29105" FT Condition: H FT BINDING 200 FT /ligand="Zn(2+)" FT /ligand_id="ChEBI:CHEBI:29105" FT Condition: H FT BINDING 279 FT /ligand="Zn(2+)" FT /ligand_id="ChEBI:CHEBI:29105" FT Condition: D FT BINDING 84 FT /ligand="substrate" FT Condition: E FT BINDING 136 FT /ligand="substrate" FT Optional; Condition: R FT BINDING 148 FT /ligand="substrate" FT Optional; Condition: R FT BINDING 173 FT /ligand="substrate" FT Condition: H FT BINDING 203 FT /ligand="substrate" FT Condition: E FT BINDING 279 FT /ligand="substrate" FT Condition: D XX Size: 406-449; Related: None; Template: Q9X034; Q58936; Scope: Bacteria Archaea Fusion: Nter: None Cter: None Duplicate: in ARCFU, SYNAS Plasmid: None Comments: None XX # Revision 1.25 2022/11/19 //