Crystal structure of PPEP-1(K101A)

Experimental Data Snapshot

  • Resolution: 2.02 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.179 

wwPDB Validation   3D Report Full Report

This is version 1.3 of the entry. See complete history


Molecular determinants of the mechanism and substrate specificity ofClostridium difficileproline-proline endopeptidase-1.

Pichlo, C.Juetten, L.Wojtalla, F.Schacherl, M.Diaz, D.Baumann, U.

(2019) J Biol Chem 294: 11525-11535

  • DOI: https://doi.org/10.1074/jbc.RA119.009029
  • Primary Citation of Related Structures:  
    6R4W, 6R4X, 6R4Y, 6R4Z, 6R50, 6R51, 6R52, 6R53, 6R54, 6R55, 6R56, 6R57, 6R58, 6R59, 6R5A, 6R5B, 6R5C, 6R9Z

  • PubMed Abstract: 

    Pro-Pro endopeptidase-1 (PPEP-1) is a secreted metalloprotease from the bacterial pathogen Clostridium difficile that cleaves two endogenous adhesion proteins. PPEP-1 is therefore important for bacterial motility and hence for efficient gut colonization during infection. PPEP-1 exhibits a unique specificity for Pro-Pro peptide bonds within the consensus sequence VNP↓PVP. In this study, we combined information from crystal and NMR structures with mutagenesis and enzyme kinetics to investigate the mechanism and substrate specificity of PPEP-1. Our analyses revealed that the substrate-binding cleft of PPEP-1 is shaped complementarily to the major conformation of the substrate in solution. We found that it possesses features that accept a tertiary amide and help discriminate P1' residues by their amide hydrogen bond-donating potential. We also noted that residues Lys-101, Trp-103, and Glu-184 are crucial for proteolytic activity. Upon substrate binding, these residues position a flexible loop over the substrate-binding cleft and modulate the second coordination sphere of the catalytic zinc ion. On the basis of these findings, we propose an induced-fit model in which prestructured substrates are recognized followed by substrate positioning within the active-site cleft and a concomitant increase in the Lewis acidity of the catalytic Zn 2+ ion. In conclusion, our findings provide detailed structural and mechanistic insights into the substrate recognition and specificity of PPEP-1 from the common gut pathogen C. difficile .

  • Organizational Affiliation

    Department of Chemistry, Institute of Organic Chemistry, University of Cologne, 50939 Cologne, Germany.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Pro-Pro endopeptidase
A, B
198Clostridioides difficileMutation(s): 0 
Gene Names: zmp1ppep-1CD630_28300
Find proteins for Q183R7 (Clostridioides difficile (strain 630))
Explore Q183R7 
Go to UniProtKB:  Q183R7
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ183R7
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.02 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.179 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.92α = 90
b = 70.94β = 90
c = 115.67γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XDSdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2019-06-12
    Type: Initial release
  • Version 1.1: 2019-06-26
    Changes: Data collection, Database references
  • Version 1.2: 2019-08-07
    Changes: Data collection, Database references
  • Version 1.3: 2024-01-24
    Changes: Advisory, Data collection, Database references, Derived calculations, Refinement description