title: Enhanced fermentation of mannitol and release of cytotoxin by Clostridium difficile in alkaline culture media.
abstract: Clostridium difficile ATCC 43255 fermented less than 10% of the mannitol in a medium at pH 7; however, when the initial pH of the medium was adjusted to 8.5 or 9, about 80% of the mannitol was fermented. Cell extracts of C. difficile phosphorylated mannitol with phosphoenolpyruvate, not ATP, indicating a phosphoenolpyruvate phosphotransferase system transport phosphorylation of mannitol. The phosphorylation product was dehydrogenated by D-mannitol-1-phosphate:NAD oxidoreductase. Growth at an initial pH of 8.5 yielded cytotoxin titers of 10(7) to 10(8) in Trypticase-yeast extract-mannitol medium, wit a titer of 10(8) as early as 13 h.
authors.affiliation: Department of Biochemistry, Microbiology & Molecular Genetics, University of Rhode Island, Kinston 02881, USA.
authors.forename: M T
authors.initials: MT
authors.lastname: Kazamias
authors.forename: J F
authors.initials: JF
authors.lastname: Sperry
mesh_terms: D016360:Clostridioides difficile / Q000378:metabolism*; D003470:Culture Media; D003603:Cytotoxins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008353:Mannitol / Q000378:metabolism*
chemical_list: D003470:Culture Media; D003603:Cytotoxins; D008353:Mannitol