title: Comparative genomic and phenomic analysis of Clostridium difficile and Clostridium sordellii, two related pathogens with differing host tissue preference.
abstract: BACKGROUND
  Clostridium difficile and C. sordellii are two anaerobic, spore forming, gram positive pathogens with a broad host range and the ability to cause lethal infections. Despite strong similarities between the two Clostridial strains, differences in their host tissue preference place C. difficile infections in the gastrointestinal tract and C. sordellii infections in soft tissues.
  
  
  RESULTS
  In this study, to improve our understanding of C. sordellii and C. difficile virulence and pathogenesis, we have performed a comparative genomic and phenomic analysis of the two. The global phenomes of C. difficile and C. sordellii were compared using Biolog Phenotype microarrays. When compared to C. difficile, C. sordellii was found to better utilize more complex sources of carbon and nitrogen, including peptides. Phenotype microarray comparison also revealed that C. sordellii was better able to grow in acidic pH conditions. Using next generation sequencing technology, we determined the draft genome of C. sordellii strain 8483 and performed comparative genome analysis with C. difficile and other Clostridial genomes. Comparative genome analysis revealed the presence of several enzymes, including the urease gene cluster, specific to the C. sordellii genome that confer the ability of expanded peptide utilization and survival in acidic pH.
  
  
  CONCLUSIONS
  The identified phenotypes of C. sordellii might be important in causing wound and vaginal infections respectively. Proteins involved in the metabolic differences between C. sordellii and C. difficile should be targets for further studies aimed at understanding C. difficile and C. sordellii infection site specificity and pathogenesis.
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. joy.scaria@sdstate.edu.|Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD, 57007, USA. joy.scaria@sdstate.edu.
authors.forename: Joy
authors.initials: J
authors.lastname: Scaria
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. haruo@yamaguchi-u.ac.jp.|Graduate School of Science and Engineering, Yamaguchi University, Yamaguchi, Japan. haruo@yamaguchi-u.ac.jp.
authors.forename: Haruo
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. cpp6@cornell.edu.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Ptak
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. kurohagi2012@gmail.com.
authors.forename: Jenn-Wei
authors.initials: JW
authors.lastname: Chen
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. yz335@cornell.edu.|Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. yz335@cornell.edu.
authors.forename: Yongzhang
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China. xkguo@shsmu.edu.cn.
authors.forename: Xiao-Kui
authors.initials: XK
authors.lastname: Guo
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA. yc42@cornell.edu.
authors.forename: Yung-Fu
authors.initials: YF
authors.lastname: Chang
mesh_terms: D016360:Clostridioides difficile / Q000235:genetics*; D047989:Paraclostridium sordellii / Q000235:genetics*; D016680:Genome, Bacterial; D023281:Genomics / Q000379:methods*; D059014:High-Throughput Nucleotide Sequencing; D058507:Host Specificity; D006863:Hydrogen-Ion Concentration; D010641:Phenotype; D010802:Phylogeny; D017422:Sequence Analysis, DNA