The domain within your query sequence starts at position 45 and ends at position 172; the E-value for the SelR domain shown below is 2.2e-52.



PFAM accession number:PF01641
Interpro abstract (IPR002579):

Peptide methionine sulphoxide reductase (Msr) reverses the inactivation of many proteins due to the oxidation of critical methionine residues by reducing methionine sulphoxide, Met(O), to methionine [ (PUBMED:10841552) ]. It is present in most living organisms, and the cognate structural gene belongs to the so-called minimum gene set [ (PUBMED:8994848) (PUBMED:8816789) ].

The domains: MsrA and MsrB, reduce different epimeric forms of methionine sulphoxide. This group represents MsrB, the crystal structure of which has been determined to 1.8A [ (PUBMED:11938352) ]. The overall structure shows no resemblance to the structures of MsrA ( IPR002569 ) from other organisms; though the active sites show approximate mirror symmetry. In each case, conserved amino acid motifs mediate the stereo-specific recognition and reduction of the substrate. Unlike the MsrA domain, the MsrB domain activates the cysteine or selenocysteine nucleophile through a unique Cys-Arg-Asp/Glu catalytic triad. The collapse of the reaction intermediate most likely results in the formation of a sulphenic or selenenic acid moiety. Regeneration of the active site occurs through a series of thiol-disulphide exchange steps involving another active site Cys residue and thioredoxin.

In a number of pathogenic bacteria, including Neisseria gonorrhoeae, the MsrA and MsrB domains are fused; the MsrA being N-terminal to MsrB. This arrangement is reversed in Treponema pallidum. In N. gonorrhoeae and Neisseria meningitidis, a thioredoxin domain is fused to the N terminus. This may function to reduce the active sites of the downstream MsrA and MsrB domains.

GO process:oxidation-reduction process (GO:0055114)
GO function:peptide-methionine (R)-S-oxide reductase activity (GO:0033743)

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