1HT3

MERCURY INDUCED MODIFICATIONS IN THE STEREOCHEMISTRY OF THE ACTIVE SITE THROUGH CYS-73 IN A SERINE PROTEASE: CRYSTAL STRUCTURE OF THE COMPLEX OF A PARTIALLY MODIFIED PROTEINASE K WITH MERCURY AT 1.8 A RESOLUTION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.164 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Mercury induced modifications in the stereochemistry of the active site through Cys-73 in a serine protease--crystal structure of the complex of a partially modified proteinase K with mercury at 1.8 A resolution

Gourinath, S.Degenhardt, M.Eschenburg, S.Moore, K.Delucas, L.J.Betzel, C.H.Singh, T.P.

(2001) Indian J.Biochem.Biophys. 38: 298-302


  • PubMed Abstract: 
  • Proteinese K (PK) isolated from Tritirachium album Limber was crystallized with HgCl2 in excess, under microgravity conditions. The intensity data were collected at 4 degrees C to 1.8 A resolution and the final R-factor after refinement for all the r ...

    Proteinese K (PK) isolated from Tritirachium album Limber was crystallized with HgCl2 in excess, under microgravity conditions. The intensity data were collected at 4 degrees C to 1.8 A resolution and the final R-factor after refinement for all the reflections was 0.164. Mercury has been found at two sites with partial occupancies (0.4 and 0.6) which are at distances of 2.48 A and 2.58 A respectively from Cys-73 Sgamma. The Cys-73 in the enzyme structure is located close to the active site residue, His-69. This region is completely buried and is not accessible to the solvent. It is rather tightly packed. Therefore, the binding of mercury distorts the stereochemistry of the neighbouring residues including those belonging to the catalytic triad. As a result of this, the Ogamma of Ser-224 is displaced by 0.6 A which causes the inactivation of proteinase K by increasing the H-bond distance to 3.7 A between Ser-224 Ogamma and His-69 Nepsilon2.


    Organizational Affiliation

    Department of Biophysics, All India Institute of Medical Sciences, New Delhi.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEINASE K
A
279Engyodontium albumGene Names: PROK
EC: 3.4.21.64
Find proteins for P06873 (Engyodontium album)
Go to UniProtKB:  P06873
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
HG
Query on HG

Download SDF File 
Download CCD File 
A
MERCURY (II) ION
Hg
BQPIGGFYSBELGY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.164 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 68.360α = 90.00
b = 68.360β = 90.00
c = 108.700γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
DENZOdata reduction
REFMACrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2000-12-27 
  • Released Date: 2001-06-27 
  • Deposition Author(s): Gourinath, S.

Revision History 

  • Version 1.0: 2001-06-27
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2018-01-24
    Type: Database references