spacer

MG 530 B

Metal-MACiE entry for MG 530 B

Magnesium ion is required for enzyme activity, and the requirement is beyond levels needed for ATP chelation. Magnesium appears to be an essential activator and there may be more than one binding site PMID7706277.


Metal in MACiE Physiological Metal Site Type
magnesium magnesium mononuclear

Resting State

There is no PDB code associated with this metal atom in the enzyme's resiting state.

MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE. The resting state enzyme should not bind Mg-ATP. If the hypothesis is correct, a representative structure for the resting state enzyme is 2ywb.


Step 01

Metal Functions

Substrate Binding

Activator. Note: It activates ATP.

Increase Electrophilicity. Note: It polarizes the P-O bond on ATP.

Electrostatic Stabiliser

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
product of MG 530 B
Download the coordinates file
Representative Structure
PDB code 1gpm
MACiE Metal Type
(Identity)
magnesium
(MG530B)
PDB Metal Type (Identity) magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(5)

The sixth ligand could be a water molecule that has been lost in the structure.


First Coordination Sphere

Ligand Type Ligand (PDB) Ligand (MACiE) Catalytic Binding Mode Contacting Atoms
Reactive Species POP 526 B- No bidentate O3,O6
Reactive Species AMP 527 B- No bidentate O1P,O3P
Water HOH 457 - No monodentate O

Step 02

Metal Functions

Not Present. Note: The Mg ion binds the ATP pyrophosphatase domain whereas this reaction step occurs in the glutaminase domain.

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.


Step 03

Metal Functions

Not Present. Note: The Mg ion binds the ATP pyrophosphatase domain whereas this reaction step occurs in the glutaminase domain.

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.


Step 04

Metal Functions

Substrate Binding

Electrostatic Stabiliser. Note: It stabilises the pentacoordinate transition state.

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.


Step 05

Metal Functions

Not Present. Note: The Mg ion binds the ATP pyrophosphatase domain whereas this reaction step occurs in the glutaminase domain.

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.


Step 06

Metal Functions

Not Present. Note: The Mg ion binds the ATP pyrophosphatase domain whereas this reaction step occurs in the glutaminase domain.

Structural Information


MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.





Right Arrow
MACiE Metal Type
(Identity)
magnesium
(MG530B)
Oxidation State 2
Coordination Geometry
(Number of ligands)
octahedral
(6)

This step has no available structures in the PDB: all the coordinating information are derived from the reaction model in MACiE.



spacer
spacer