Entry M0201    propionyl-CoA carboxylase

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Step 04

Reaction occurs in the alpha-subunit. The oxyanion re-forms the carbonyl group, causing the C=N bond of the activated biotin to add to the carbon dioxide in a nucleophilic manner.

GIF of Reaction Step M0201.stg04

Comment: This step occurs in the alpha-subunit, the biotin carboxylase domain.


Bimolecular Nucleophilic Addition

Mechanism Components

Bond Formation
Bond Order Change
Intermediate Formation
Enzyme Not Regenerated

Amino acids involved in the reaction step.

There are no amino acid residues associated with this reaction step

Organic Cofactors involved in the reaction step

Cofactor Type Cofactor Activity Function
Biotin BTN5600 reactant Nucleophile
Polar Interaction

Metal Cofactors involved in Step 04

Metal Type Metal Identity Chain Activity Function
magnesium MG(not in PDB) 1 x spectator Substrate Binding
Electrostatic Stabiliser

Reactive Centre

Bonds Formed Bonds Cleaved Bonds Changed in Order Atom Types Involved
The C-O bond changes from a single to double bond
The C-N bond changes from a double to single bond
The C-O bond changes from a double to single bond

View similar reactions in MACiE.