Any feedback?
Please rate this page
(ecexplorer.php)
(0/150)

BRENDA support

EC Explorer

EC 2.5.1.151 Details
EC number
2.5.1.151
Accepted name
alkylcobalamin dealkylase
Reaction
(1) methylcob(III)alamin + [alkylcobalamin dealkylase] + glutathione = cob(I)alamin-[alkylcobalamin dealkylase] + an S-methyl glutathione;;(2) adenosylcob(III)alamin + [alkylcobalamin dealkylase] + glutathione = cob(I)alamin-[alkylcobalamin dealkylase] + S-adenosyl glutathione
Other name(s)
MMACHC (gene name), alkylcobalamin:glutathione S-alkyltransferase, alkylcobalamin reductase
Systematic name
methylcobalamin:glutathione S-methyltransferase
Comment
This mammalian enzyme, which is cytosolic, can bind internalized methylcob(III)alamin and adenosylcob(III)alamin and process them to cob(I)alamin using the thiolate of glutathione for nucleophilic displacement. The product remains bound to the protein, and, following its oxidation to cob(II)alamin, is transferred by the enzyme, together with its interacting partner MMADHC, directly to downstream enzymes involved in adenosylcob(III)alamin and methylcob(III)alamin biosynthesis. In addition to its dealkylase function, the enzyme also catalyse an entirely different decyanase reaction with cyanocob(III)alamin (cf. EC 1.16.1.6, cyanocobalamin reductase).
History
created 2018, modified 2021
EC Tree
2.5.1.12 created 1972, deleted 1976
2.5.1.13 created 1972, deleted 1976
2.5.1.14 created 1972, deleted 1976
2.5.1.37 created 1989, deleted 2004
2.5.1.40 created 1992, deleted 1999