1ISO

ISOCITRATE DEHYDROGENASE: STRUCTURE OF AN ENGINEERED NADP+--> NAD+ SPECIFICITY-REVERSAL MUTANT


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Determinants of cofactor specificity in isocitrate dehydrogenase: structure of an engineered NADP+ --> NAD+ specificity-reversal mutant.

Hurley, J.H.Chen, R.Dean, A.M.

(1996) Biochemistry 35: 5670-5678

  • DOI: 10.1021/bi953001q

  • PubMed Abstract: 
  • The 7-fold mutation Cys201Met/Cys332Tyr/Lys344Asp/Tyr345Ile/Val35 1Ala/Tyr391Lys/Arg395Ser converts the cofactor specificity of Escherichia coli isocitrate dehydrogenase from a 7000-fold preference for NADP+ to a 200-fold preference for NAD+, with ov ...

    The 7-fold mutation Cys201Met/Cys332Tyr/Lys344Asp/Tyr345Ile/Val35 1Ala/Tyr391Lys/Arg395Ser converts the cofactor specificity of Escherichia coli isocitrate dehydrogenase from a 7000-fold preference for NADP+ to a 200-fold preference for NAD+, with overall activity comparable to that of wild-type NAD+-dependent isocitrate dehydrogenases. The structure of the NAD+-dependent mutant has been determined and refined to a working R-factor of 0.186 at 1.9 A resolution. The structure shows that NADP+ affinity is destroyed by removing favorable interactions between the 2'-phosphate and Tyr345, Tyr391, and Arg395 and by adding a repulsive interaction with Asp344. NAD+ affinity is enhanced by adding hydrogen bonds between Asp344 and the free 2'-hydroxyl. The favorable Asp344-2'-OH interaction requires a change in the pucker of the ribose to C2' endo and a shift in the adenine ring. The ring shift is made possible by a series of changes in steric packing interactions. The linchpin for repacking in the adenosine binding site is residue 351. The side chain of this "second layer" residue dictates packing of the surrounding "first layer" residues which interact with the 2' moiety and, in turn, directly determine specificity.


    Organizational Affiliation

    Laboratory of Molecular Biology, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0580, USA. HURLEY@TOVE.NIDDK.NIH.GOV




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ISOCITRATE DEHYDROGENASE
A
416Escherichia coli (strain K12)Mutation(s): 7 
Gene Names: icd (icdA, icdE)
EC: 1.1.1.42
Find proteins for P08200 (Escherichia coli (strain K12))
Go to UniProtKB:  P08200
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
NAD
Query on NAD

Download SDF File 
Download CCD File 
A
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.186 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 102.400α = 90.00
b = 102.400β = 90.00
c = 150.600γ = 90.00
Software Package:
Software NamePurpose
X-PLORmodel building
SCALEPACKdata scaling
DENZOdata reduction
X-PLORrefinement
X-PLORphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 1996-03-01 
  • Released Date: 1996-12-07 
  • Deposition Author(s): Hurley, J.H.

Revision History 

  • Version 1.0: 1996-12-07
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance