1H, 13C, and 15N resonance assignments of an enzymatically active domain from the catalytic component (CDTa, residues 216-420) of a binary toxin from Clostridium difficile.

摘要: Clostridium difficile is a bacterial pathogen and the most commonly reported source of nosocomial infection in industrialized nations. Symptoms C. (CDI) include antibiotic-associated diarrhea, pseudomembranous colitis, sepsis death. Over last decade, rates severity hospital infections North America Europe have increased dramatically correlate with emergence hypervirulent strain characterized by presence binary toxin, CDT (C. toxin). The toxin consists an enzymatic component (CDTa) cellular binding (CDTb) that together form active complex. CDTa harbors pair structurally similar but functionally distinct domains, N-terminal domain (residues 1-215; (1-215)CDTa) interacts CDTb C-terminal 216-420; (216-420)CDTa) intact ADP-ribosyltransferase (ART) site. Reported here are (1)H, (13)C, (15)N backbone resonance assignments 23 kDa, 205 amino acid CDTa, termed (216-420)CDTa. These NMR for (216-420)CDTa represent first family ART toxins provide framework detailed characterization solution-state protein structure determination, dynamic studies this domain, as well NMR-based drug discovery efforts.