1ANC

ANIONIC TRYPSIN MUTANT WITH SER 214 REPLACED BY LYS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Work: 0.154 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Perturbing the polar environment of Asp102 in trypsin: consequences of replacing conserved Ser214.

McGrath, M.E.Vasquez, J.R.Craik, C.S.Yang, A.S.Honig, B.Fletterick, R.J.

(1992) Biochemistry 31: 3059-3064

  • Primary Citation of Related Structures:  1ANB

  • PubMed Abstract: 
  • Much of the catalytic power of trypsin is derived from the unusual buried, charged side chain of Asp102. A polar cave provides the stabilization for maintaining the buried charge, and it features the conserved amino acid Ser214 adjacent to Asp102. Se ...

    Much of the catalytic power of trypsin is derived from the unusual buried, charged side chain of Asp102. A polar cave provides the stabilization for maintaining the buried charge, and it features the conserved amino acid Ser214 adjacent to Asp102. Ser214 has been replaced with Ala, Glu, and Lys in rat anionic trypsin, and the consequences of these changes have been determined. Three-dimensional structures of the Glu and Lys variant trypsins reveal that the new 214 side chains are buried. The 2.2-A crystal structure (R = 0.150) of trypsin S214K shows that Lys214 occupies the position held by Ser214 and a buried water molecule in the buried polar cave. Lys214-N zeta is solvent inaccessible and is less than 5 A from the catalytic Asp102. The side chain of Glu214 (2.8 A, R = 0.168) in trypsin S214E shows two conformations. In the major one, the Glu carboxylate in S214E forms a hydrogen bond with Asp102. Analytical isoelectrofocusing results show that trypsin S214K has a significantly different isoelectric point than trypsin, corresponding to an additional positive charge. The kinetic parameter kcat demonstrates that, compared to trypsin, S214K has 1% of the catalytic activity on a tripeptide amide substrate and S214E is 44% as active. Electrostatic potential calculations provide corroboration of the charge on Lys214 and are consistent with the kinetic results, suggesting that the presence of Lys214 has disturbed the electrostatic potential of Asp102.


    Organizational Affiliation

    Department of Biochemistry and Biophysics, University of California, San Francisco 94143.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ANIONIC TRYPSIN
A
223Rattus norvegicusGene Names: Prss2 (Try2)
EC: 3.4.21.4
Find proteins for P00763 (Rattus norvegicus)
Go to UniProtKB:  P00763
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
BEN
Query on BEN

Download SDF File 
Download CCD File 
A
BENZAMIDINE
C7 H8 N2
PXXJHWLDUBFPOL-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Work: 0.154 
  • Space Group: I 2 3
Unit Cell:
Length (Å)Angle (°)
a = 124.380α = 90.00
b = 124.380β = 90.00
c = 124.380γ = 90.00
Software Package:
Software NamePurpose
XENGENdata collection
XENGENdata reduction
XENGENdata scaling
PROLSQrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1997-04-01
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance