CATH Classification

Domain Context

CATH Clusters

Superfamily Dihydropteroate synthase-like
Functional Family Methionine synthase

Enzyme Information

2.1.1.13
Methionine synthase.
based on mapping to UniProt Q99707
5-methyltetrahydrofolate + L-homocysteine = tetrahydrofolate + L-methionine.
-!- The enzyme becomes inactivated occasionally during its cycle by oxidation of Co(I) to Co(II). -!- Reactivation by reductive methylation is catalyzed by the enzyme itself, with S-adenosyl-L-methionine as the methyl donor and a reducing system. -!- For the mammalian enzyme, the reducing system involves NADPH and EC 1.16.1.8. -!- In bacteria, the reducing agent is flavodoxin, and no further catalyst is needed (the flavodoxin is kept in the reduced state by NADPH and EC 1.18.1.2). -!- Acts on the monoglutamate as well as the triglutamate folate, in contrast with EC 2.1.1.14, which acts only on the triglutamate.

UniProtKB Entries (1)

Q99707
METH_HUMAN
Homo sapiens
Methionine synthase

PDB Structure

PDB 4CCZ
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Crystal Structure of Human 5-Methyltetrahydrofolate-Homocysteine Methyltransferase, the Homocysteine and Folate Binding Domains
Vollmar, M., Kiyani, W., Krojer, T., Goubin, S., Burgess-Brown, N., von Delft, F., Oppermann, U., Edwards, A., Arrowsmith, C., Bountra, C., Yue, W.W.
To be Published