3AAT

ACTIVITY AND STRUCTURE OF THE ACTIVE-SITE MUTANTS R386Y AND R386F OF ESCHERICHIA COLI ASPARTATE AMINOTRANSFERASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Activity and structure of the active-site mutants R386Y and R386F of Escherichia coli aspartate aminotransferase.

Danishefsky, A.T.Onnufer, J.J.Petsko, G.A.Ringe, D.

(1991) Biochemistry 30: 1980-1985


  • PubMed Abstract: 
  • Arginine-386, the active-site residue of Escherichia coli aspartate aminotransferase (EC 2.6.1.1) that binds the substrate alpha-carboxylate, was replaced with tyrosine and phenylalanine by site-directed mutagenesis. This experiment was undertaken to ...

    Arginine-386, the active-site residue of Escherichia coli aspartate aminotransferase (EC 2.6.1.1) that binds the substrate alpha-carboxylate, was replaced with tyrosine and phenylalanine by site-directed mutagenesis. This experiment was undertaken to elucidate the roles of particular enzyme-substrate interactions in triggering the substrate-induced conformational change in the enzyme. The activity and crystal structure of the resulting mutants were examined. The apparent second-order rate constants of both of these mutants are reduced by more than 5 orders of magnitude as compared to that of wild-type enzyme, though R386Y is slightly more active than R386F. The 2.5-A resolution structure of R386F in its native state was determined by using difference Fourier methods. The overall structure is very similar to that of the wild-type enzyme in the open conformation. The position of the Phe-386 side chain, however, appears to shift with respect to that of Arg-386 in the wild-type enzyme and to form new contacts with neighboring residues.


    Related Citations: 
    • Preliminary X-Ray Data for Aspartate Aminotransferase from Escherichia Coli
      Smith, D.L.,Ringe, D.,Finlayson, W.L.,Kirsch, J.F.
      (1986) J.Mol.Biol. 191: 301
    • 2.8-Angstroms-Resolution Crystal Structure of an Active-Site Mutant of Aspartate Aminotransferse from Escherichia Coli
      Smith, D.L.,Almo, S.C.,Toney, M.D.,Ringe, D.
      (1989) Biochemistry 28: 8161


    Organizational Affiliation

    Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ASPARTATE AMINOTRANSFERASE
A
396Escherichia coli (strain K12)Mutation(s): 1 
Gene Names: aspC
EC: 2.6.1.1
Find proteins for P00509 (Escherichia coli (strain K12))
Go to UniProtKB:  P00509
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
PLP
Query on PLP

Download SDF File 
Download CCD File 
A
PYRIDOXAL-5'-PHOSPHATE
VITAMIN B6 Phosphate
C8 H10 N O6 P
NGVDGCNFYWLIFO-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 156.000α = 90.00
b = 87.600β = 90.00
c = 78.800γ = 90.00
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1992-01-15
    Type: Initial release
  • Version 1.1: 2008-03-03
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2012-07-25
    Type: Structure summary