Annotations: 5FA9

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	SelR	e5fa9A2	A: beta complex topology	X: ETN0001 domain-like (From Homology)	H: ETN0001 domain-like	T: Mss4-like	F: SelR	ECOD (1.6)
A	PMSR	e5fa9A1	A: a+b two layers	X: Alpha-beta plaits	H: HMA-related	T: Peptide methionine sulfoxide reductase	F: PMSR	ECOD (1.6)
B	SelR	e5fa9B1	A: beta complex topology	X: ETN0001 domain-like (From Homology)	H: ETN0001 domain-like	T: Mss4-like	F: SelR	ECOD (1.6)
B	PMSR	e5fa9B2	A: a+b two layers	X: Alpha-beta plaits	H: HMA-related	T: Peptide methionine sulfoxide reductase	F: PMSR	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.30.1060.10	Alpha Beta	2-Layer Sandwich	Peptide Methionine Sulfoxide Reductase	Chain A	CATH (utative)
A	2.170.150.20	Mainly Beta	Beta Complex	Metal Binding Protein, Guanine Nucleotide Exchange Factor	Chain A	CATH (utative)
B	3.30.1060.10	Alpha Beta	2-Layer Sandwich	Peptide Methionine Sulfoxide Reductase	Chain A	CATH (utative)
B	2.170.150.20	Mainly Beta	Beta Complex	Metal Binding Protein, Guanine Nucleotide Exchange Factor	Chain A	CATH (utative)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF01625	Peptide methionine sulfoxide reductase (PMSR)	Peptide methionine sulfoxide reductase	This enzyme repairs damaged proteins. Methionine sulfoxide in proteins is reduced to methionine.	Domain
A, B	PF01641	SelR domain (SelR)	SelR domain	Methionine sulfoxide reduction is an important process, by which cells regulate biological processes and cope with oxidative stress. MsrA, a protein involved in the reduction of methionine sulfoxides in proteins, has been known for four decades and h ...	Methionine sulfoxide reduction is an important process, by which cells regulate biological processes and cope with oxidative stress. MsrA, a protein involved in the reduction of methionine sulfoxides in proteins, has been known for four decades and has been extensively characterised with respect to structure and function. However, recent studies revealed that MsrA is only specific for methionine-S-sulfoxides. Because oxidised methionines occur in a mixture of R and S isomers in vivo, it was unclear how stereo-specific MsrA could be responsible for the reduction of all protein methionine sulfoxides. It appears that a second methionine sulfoxide reductase, SelR, evolved that is specific for methionine-R-sulfoxides, the activity that is different but complementary to that of MsrA. Thus, these proteins, working together, could reduce both stereoisomers of methionine sulfoxide. This domain is found both in SelR proteins and fused with the peptide methionine sulfoxide reductase enzymatic domain Pfam:PF01625. The domain has two conserved cysteines and histidines. The domain binds both selenium and zinc [2]. The final cysteine is found to be replaced by the rare amino acid selenocysteine in some members of the family [1]. This family has methionine-R-sulfoxide reductase activity [2].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	Peptide methionine sulfoxide reductase MsrA	oxidoreductase activity, acting on a sulfur group of donors oxidoreductase activity oxidoreductase activity, acting on a sulfur group of donors, disulfide as acceptor catalytic activity peptide-methionine (R)-S-oxide reductase activity L-methionine:thioredoxin-disulfide S-oxidoreductase activity peptide-methionine (S)-S-oxide reductase activity	response to oxidative stress response to stimulus response to stress macromolecule modification metabolic process cellular process primary metabolic process protein metabolic process macromolecule metabolic process protein modification process protein repair	cellular anatomical structure intracellular anatomical structure cytoplasm

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR028427	Peptide methionine sulfoxide reductase MsrB	Family
A, B	IPR002569	Peptide methionine sulphoxide reductase MsrA domain	Domain
A, B	IPR036509	Peptide methionine sulphoxide reductase MsrA superfamily	Homologous Superfamily
A, B	IPR011057	Mss4-like superfamily	Homologous Superfamily
A, B	IPR002579	Peptide methionine sulphoxide reductase MrsB domain	Domain

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.