148L

A COVALENT ENZYME-SUBSTRATE INTERMEDIATE WITH SACCHARIDE DISTORTION IN A MUTANT T4 LYSOZYME


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

A covalent enzyme-substrate intermediate with saccharide distortion in a mutant T4 lysozyme.

Kuroki, R.Weaver, L.H.Matthews, B.W.

(1993) Science 262: 2030-2033


  • PubMed Abstract: 
  • The glycosyl-enzyme intermediate in lysozyme action has long been considered to be an oxocarbonium ion, although precedent from other glycosidases and theoretical considerations suggest it should be a covalent enzyme-substrate adduct. The mutation of ...

    The glycosyl-enzyme intermediate in lysozyme action has long been considered to be an oxocarbonium ion, although precedent from other glycosidases and theoretical considerations suggest it should be a covalent enzyme-substrate adduct. The mutation of threonine 26 to glutamic acid in the active site cleft of phage T4 lysozyme (T4L) produced an enzyme that cleaved the cell wall of Escherichia coli but left the product covalently bound to the enzyme. The crystalline complex was nonisomorphous with wild-type T4L, and analysis of its structure showed a covalent linkage between the product and the newly introduced glutamic acid 26. The covalently linked sugar ring was substantially distorted, suggesting that distortion of the substrate toward the transition state is important for catalysis, as originally proposed by Phillips. It is also postulated that the adduct formed by the mutant is an intermediate, consistent with a double displacement mechanism of action in which the glycosidic linkage is cleaved with retention of configuration as originally proposed by Koshland. The peptide part of the cell wall fragment displays extensive hydrogen-bonding interactions with the carboxyl-terminal domain of the enzyme, consistent with previous studies of mutations in T4L.


    Related Citations: 
    • Structure of Bacteriophage T4 Lysozyme Refined at 1.7 Angstroms Resolution
      Weaver, L.H.,Matthews, B.W.
      (1987) J.Mol.Biol. 193: 189


    Organizational Affiliation

    Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene 97403.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
T4 LYSOZYME
E
164Enterobacteria phage T4Gene Names: E
EC: 3.2.1.17
Find proteins for P00720 (Enterobacteria phage T4)
Go to UniProtKB:  P00720
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
SUBSTRATE CLEAVED FROM CELL WALL OF ESCHERICHIA COLI
S
4N/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MUB
Query on MUB

Download SDF File 
Download CCD File 
S
N-ACETYLMURAMIC ACID
C11 H19 N O8
MNLRQHMNZILYPY-MDMHTWEWSA-N
 Ligand Interaction
BME
Query on BME

Download SDF File 
Download CCD File 
E
BETA-MERCAPTOETHANOL
C2 H6 O S
DGVVWUTYPXICAM-UHFFFAOYSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
S
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Modified Residues  3 Unique
IDChainsTypeFormula2D DiagramParent
API
Query on API
S
L-PEPTIDE LINKINGC7 H14 N2 O4LYS
FGA
Query on FGA
S
D-gamma-peptide, C-delta linkingC5 H9 N O4

--

DAL
Query on DAL
S
D-PEPTIDE LINKINGC3 H7 N O2

--

Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 50.900α = 90.00
b = 67.300β = 90.00
c = 49.600γ = 90.00
Software Package:
Software NamePurpose
TNTrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1994-04-30
    Type: Initial release
  • Version 1.1: 2008-05-22
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2011-07-27
    Type: Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary
  • Version 1.4: 2017-11-29
    Type: Derived calculations, Other