title: Secretome analysis of Clostridium difficile strains.
abstract: Clostridium difficile causes infections ranging from mild C. difficile-associated diarrhea to severe pseudomembranous colitis. Since 2003 new hypervirulent C. difficile strains (PCR ribotype 027) emerged characterized by a dramatically increased mortality. The secretomes of the three C. difficile strains CDR20291, CD196, and CD630 were analyzed and compared. Proteins were separated and analyzed by means of SDS--PAGE and LC-MS. MS data were analyzed using Mascot and proteins were checked for export signals with SecretomeP and SignalP. LC-MS analysis revealed 158 different proteins in the supernatant of C. difficile. Most of the identified proteins originate from the cytoplasm. Thirty-two proteins in CDR20291, 36 in CD196 and 26 in CD630 were identified to be secreted by C. difficile strains. Those were mainly S-layer proteins, substrate-binding proteins of ABC-transporters, cell wall hydrolases, pilin and unknown hypothetical proteins. Toxin A and toxin B were identified after growth in brain heart infusion medium using immunological techniques. The ADP-ribosyltransferase-binding component protein, which is a part of the binary toxin CDT, was only identified in the hypervirulent ribotype 027 strains. Further proteins that are secreted specifically by hypervirulent strains were identified.
authors.affiliation: Hannover Medical School, Institute of Toxicology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Boetzkes
authors.forename: Katharina Wiebke
authors.initials: KW
authors.lastname: Felkel
authors.forename: Johannes
authors.initials: J
authors.lastname: Zeiser
authors.forename: Nelli
authors.initials: N
authors.lastname: Jochim
authors.forename: Ingo
authors.initials: I
authors.lastname: Just
authors.forename: Andreas
authors.initials: A
authors.lastname: Pich
mesh_terms: D036002:ADP Ribose Transferases / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D001427:Bacterial Toxins / Q000378:metabolism; D002853:Chromatography, Liquid; D016360:Clostridioides difficile / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D013058:Mass Spectrometry; D020543:Proteome; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D020543:Proteome; D036002:ADP Ribose Transferases