CATH Classification
| Level | CATH Code | Description | 
|---|---|---|
|   | 2 | Mainly Beta | 
|   | 2.170 | Beta Complex | 
|   | 2.170.150 | Metal Binding Protein, Guanine Nucleotide Exchange Factor; Chain A | 
|   | 2.170.150.20 | Peptide methionine sulfoxide reductase. | 
Domain Context
CATH Clusters
| Superfamily | Peptide methionine sulfoxide reductase. | 
| Functional Family | methionine-R-sulfoxide reductase B1 | 
Enzyme Information
| 1.8.4.12 | Peptide-methionine (R)-S-oxide reductase. based on mapping to UniProt Q9JLC3 Peptide-L-methionine + thioredoxin disulfide + H(2)O = peptide-L- methionine (R)-S-oxide + thioredoxin. -!- The reaction occurs in the reverse direction to that shown above. -!- Exhibits high specificity for reduction of the R-form of methionine S-oxide, with higher activity being observed with L-methionine S-oxide than with D-methionine S-oxide. -!- While both free and protein-bound methionine (R)-S-oxide act as substrates, the activity with the peptide-bound form is far greater. -!- Plays a role in preventing oxidative-stress damage caused by reactive oxygen species by reducing the oxidized form of methionine back to methionine and thereby reactivating peptides that had been damaged. -!- The reaction proceeds via a sulfenic-acid intermediate. -!- For MsrB2 and MsrB3, thioredoxin is a poor reducing agent but thionein works well. | 
| 1.8.4.14 | L-methionine (R)-S-oxide reductase. based on mapping to UniProt Q9JLC3 L-methionine + thioredoxin disulfide + H(2)O = L-methionine (R)-S-oxide + thioredoxin. -!- Unlike EC 1.8.4.12 this enzyme cannot use peptide-bound methionine (R)-S-oxide as a substrate. -!- Differs from EC 1.8.4.13, in that L-methionine (S)-S-oxide is not a substrate. -!- Formerly EC 1.8.4.5. | 
UniProtKB Entries (1)
| Q9JLC3 | MSRB1_MOUSE Mus musculus Methionine-R-sulfoxide reductase B1 | 
PDB Structure
| PDB | 2KV1 | 
| External Links | |
| Method | SOLUTION NMR | 
| Organism | |
| Primary Citation | Insights into function, catalytic mechanism, and fold evolution of selenoprotein methionine sulfoxide reductase B1 through structural analysis J.Biol.Chem. | 
