Mechanical Stability of a High-Affinity Toxin Anchor from the Pathogen Clostridium perfringens

Milles, Lukas F.; Bayer, Edward A.; Nash, Michael A. und Gaub, Hermann E. (2017): Mechanical Stability of a High-Affinity Toxin Anchor from the Pathogen Clostridium perfringens. In: Journal of Physical Chemistry B, Bd. 121, Nr. 15: S. 3620-3625

Abstract

The opportunistic pathogen Clostridium perfringens assembles its toxins and carbohydrate-active enzymes by the high-affinity cohesin-dockerin (Coh-Doc) interaction. Coh-Doc interactions characterized previously have shown considerable resilience toward mechanical stress. Here;we aimed to determine the mechanics of this interaction from C. perfringens in the context of a pathogen. Using atomic force microscopy based single-molecule forte spectroscopy (AFM-SMFS) we probed the mechanical properties of the interaction of a dockerin from the mu-toxin with the GH84C X82 cohesin domain of C. perfringens. Most probable complex rupture forces were found to be approximately 60 pN and an estimate of the binding potential width was performed. The dockerin was expressed with its adjacent FIVAR (found in various architectures) domain, whose mechanostability we determined to be very similar to the complex. Additionally, fast refolding of this domain was observed. The Coh-Doc interaction from C. perfringens is the mechanically weakest observed to date. Our results establish the relevant force range of toxin assembly mechanics in pathogenic Clostridia.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Fakultätsübergreifende Einrichtungen: Center for NanoScience (CENS)
• Themengebiete: 500 Naturwissenschaften und Mathematik > 500 Naturwissenschaften ; 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1520-6106
• Sprache: Englisch