DFG Research Training Group "TJ-Train" (GRK 2318)
Tight junctions and their proteins
Molecular features and actions in health and disease

Project A2

Priv.-Doz. Dr. Jörg Piontek1      &    Dr. Gerd Krause2 

1Institute of Clinical Physiology, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin
2Structural Bioinformatics & Protein Design, Leibniz Research Institute of Molecular Pharmacology (FMP), Berlin-Buch

Structure-based modification of Clostridium perfringens enterotoxin to target claudins

Clostridium perfringens enterotoxin (CPE) causes one of the most common food borne illnesses. CPE binds to tight junction (TJ) proteins (e.g. claudin-3 and -4) and subsequently forms pores in the membrane leading to damage of epithelial cells. Due to its cytotoxicity, CPE is used for targeting of claudin-overexpressing tumor cells. In contrast, the c-terminal domain cCPE of CPE is non-toxic and contains the claudin binding domain. cCPE is used as a TJ modulator to increase paracellular drug delivery. Previously, we elucidated in structure-based studies the molecular mechanism of the CPE-claudin interaction and designed CPE- or cCPE-variants with shifted claudin subtypespecificity (e.g. binding to claudin-1 or -5). 

Aim of this project are expanded structure-function studies to design and to test variants of cCPE and CPE as claudin subtype-specific and in turn tissue-specific biologicals for (i) improved drug delivery by TJ-modulation, (ii) molecular diagnosis or (iii) cytotoxic treatment of carcinomas.

Methods: Molecular modelling, site-directed mutagenesis, expression and purification of recombinant proteins, protein-protein interaction assays, cell culture of differentiated epithelial and carcinoma cells, immunocytochemistry and confocal microscopy. Activity of cCPE- and CPE-variants will be tested by measurements of transepithelial resistance and paracellular solute permeability as well as imaging and cytotoxicity assays with cell lines and in vivo xenotransplant tumor models.

PhD doctoral student

  • Laura-Sophie Beier

Project-related publications

If a paper is not accessible, please mail to  

  1. Baumholtz AI, Simard A, Nikolopoulou E, Oosenbrug M, Collins MM, Piontek A, Krause G, Piontek J, Greene NDE, Ryan AK (2017) Claudins are essential for cell shape changes and convergent extension movements during neural tube closure. Dev. Biol. ###: ###-### [PubMed] [WebPage] [PDF]

  2. Liao Z, Yang Z, Piontek A, Eichner M, Krause G, Li L, Piontek J, Zhang J (2016) Specific binding of a mutated fragment of Clostridium perfringens enterotoxin to endothelial claudin-5 and its modulation of cerebral vascular permeability. Neuroscience 327: 53-63

  3. Protze J, Eichner M, Piontek A, Dinter S, Rossa J, Blecharz KG, Vajkoczy P, Piontek J*, Krause G* (*shared last authorship) (2015) Directed structural modification of Clostridium perfringens enterotoxin to enhance binding to claudin-5. Cell. Mol. Life Sci. 72: 1417-1432

  4. Zhang J, Ni C, Yang Z, Piontek A, Chen H, Wang S, Fan Y, Qin Z, Piontek J (2015) Specific binding of Clostridium perfringens enterotoxin fragment to claudin-b and modulation of zebrafish epidermal barrier. Exp. Dermatol. 24: 605-610

  5. Rossa J, Protze J, Kern C, Piontek A, Günzel D, Krause G*, Piontek J* (*shared last authorship) (2014) Molecular and structural transmembrane determinants critical for embedding claudin-5 into tight junctions reveal a distinct four-helix bundle arrangement. Biochem. J. 464: 49-60

  6. Hülper P, Veszelka S, Walter FR, Wolburg H, Fallier-Becker P, Piontek J, Blasig IE, Lakomek M, Kugler W, Deli MA (2013) Acute effects of short-chain alkylglycerols on blood-brain barrier properties of cultured brain endothelial cells. Br. J. Pharmacol. 169: 1561-1573

  7. Veshnyakova A*, Piontek J* (*shared first authorship), Protze J, Waziri N, Heise I, Krause G (2012) Mechanism of Clostridium perfringens enterotoxin interaction with claudin-3/-4 protein suggests structural modifications of the toxin to target specific claudin. J. Biol. Chem. 287: 1698-1708

  8. Walther W, Petkov S, Kuvardina ON, Aumann J, Kobelt D, Fichtner I, Lemm M, Piontek J, Blasig IE, Stein U, Schlag PM (2012) Novel Clostridium perfringens enterotoxin suicide gene therapy for selective treatment of claudin-3 and -4 overexpressing tumors. Gene Ther. 19: 494-503

  9. Piehl C*, Piontek J* (*shared first authorship), Cording J, Wolburg H, Blasig IE (2010) Participation of the second extracellular loop of claudin-5 in paracellular tightening against ions, small and large molecules. Cell. Mol. Life Sci. 67: 2131-2140

  10. Lohrberg D, Schümann M, Piontek J, Winkler L, Krause E, Blasig IE, Haseloff RF (2009) A proteomic approach for identification of tight junction-associated proteins, based on claudin affinity to Clostridium perfringens enterotoxin. BMC Mol. Biol. 10: 61 (printed pages 1-8)

  11. Winkler L, Wenzel A, Gehring C, Piehl C, Mueller SL, Krause G, Blasig IE, Piontek J (2009) Molecular determinants of the interaction between Clostridium perfringens enterotoxin and claudin-3. J. Biol. Chem. 284: 18863-18872