The domain within your query sequence starts at position 18 and ends at position 139; the E-value for the ARD domain shown below is 3.2e-55.

PAFLLLDADKYENDPELEKIRKMRNYSWMDIITICKDTLPNYEEKIKMFFEEHLHLDEEI
RYILEGSGYFDVRDKEDKWIRISMEKGDMITLPAGIYHRFTLDEKNYVKAMRLFVGEPVW
TP

ARD

ARD
PFAM accession number:PF03079
Interpro abstract (IPR004313):

The two acireductone dioxygenase enzymes (ARD and ARD', previously known as E-2 and E-2') from Klebsiella pneumoniae share the same amino acid sequence Q9ZFE7 but bind different metal ions: ARD binds Ni2+, ARD' binds Fe2+ [ (PUBMED:9880484) ]. ARD and ARD' can be experimentally interconverted by removal of the bound metal ion and reconstitution with the appropriate metal ion. The two enzymes share the same substrate, 1,2-dihydroxy-3-keto-5-(methylthio)pentene, but yield different products. ARD' yields the alpha-keto precursor of methionine (and formate), thus forming part of the ubiquitous methionine salvage pathway that converts 5'-methylthioadenosine (MTA) to methionine. This pathway is responsible for the tight control of the concentration of MTA, which is a powerful inhibitor of polyamine biosynthesis and transmethylation reactions [ (PUBMED:11371200) ]. ARD yields methylthiopropanoate, carbon monoxide and formate, and thus prevents the conversion of MTA to methionine. The role of the ARD catalysed reaction is unclear: methylthiopropanoate is cytotoxic, and carbon monoxide can activate guanylyl cyclase, leading to increased intracellular cGMP levels [ (PUBMED:11371200) (PUBMED:9880484) ].

Eukaryotic aci-reductone dioxygenase (ARD), also known as 1,2-dihydroxy-3-keto-5-methylthiopentene dioxygenase, acts in the methionine salvage pathway [ (PUBMED:15938715) ]. Several homologous ARD genes have been identified in plants [ (PUBMED:16297065) ].

GO process:oxidation-reduction process (GO:0055114)
GO function:acireductone dioxygenase [iron(II)-requiring] activity (GO:0010309)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry ARD