title: Cell extract-containing medium for culture of intracellular fastidious bacteria.
abstract: The culture of fastidious microorganisms is a critical step in infectious disease studies. As a proof-of-concept experiment, we evaluated an empirical medium containing eukaryotic cell extracts for its ability to support the growth of Coxiella burnetii. Here, we demonstrate the exponential growth of several bacterial strains, including the C. burnetii Nine Mile phase I and phase II strains, and C. burnetii isolates from humans and animals. Low-oxygen-tension conditions and the presence of small hydrophilic molecules and short peptides were critical for facilitating growth. Moreover, bacterial antigenicity was conserved, revealing the potential for this culture medium to be used in diagnostic tests and in the elaboration of vaccines against C. burnetii. We were also able to grow the majority of previously tested intracellular and fastidious bacterial species, including Tropheryma whipplei, Mycobacterium bovis, Leptospira spp., Borrelia spp., and most putative bioterrorism agents. However, we were unable to culture Rickettsia africae and Legionella spp. in this medium. The versatility of this medium should encourage its use as a replacement for the cell-based culture systems currently used for growing several facultative and putative intracellular bacterial species.
authors.affiliation: Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, INSERM 1095, Marseille, France.
authors.forename: Sudhir
authors.initials: S
authors.lastname: Singh
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Kowalczewska
authors.forename: Sophie
authors.initials: S
authors.lastname: Edouard
authors.forename: Carole
authors.initials: C
authors.lastname: Eldin
authors.forename: Céline
authors.initials: C
authors.lastname: Perreal
authors.forename: Pascal
authors.initials: P
authors.lastname: Weber
authors.forename: Said
authors.initials: S
authors.lastname: Azza
authors.forename: Didier
authors.initials: D
authors.lastname: Raoult
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques / Q000379:methods*; D002457:Cell Extracts / Q000302:isolation & purification; D016997:Coxiella burnetii / Q000254:growth & development* / Q000302:isolation & purification*; D003470:Culture Media / Q000737:chemistry*; D006801:Humans; D050356:Lipid Metabolism; D010100:Oxygen / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011778:Q Fever / Q000175:diagnosis* / Q000662:veterinary*
chemical_list: D002457:Cell Extracts; D003470:Culture Media; D010455:Peptides; D010100:Oxygen