19th International CODATA Conference
Category: Knowledge Discovery

Toward the virtual cell genome-based design of a cell-free culture medium for intracellular parasite, Tropheryma whipplei

H. Ogata, P. Renesto, D. Raoult., JM. Claverie (Jean-Michel.Claverie@igs.cnrs-mrs.fr)
Structural & Genomic Information Laboratory, CNRS, France


Empirical approaches have guided the development of bacterial cultures. The availability of sequenced genomes now provides opportunities to define culture media for growth of fastidious pathogens with computer modeling of metabolic networks. A key issue is the possibility of growing host-dependent bacteria in cell-free conditions. The genome sequence of Tropheryma whipplei, an actinobacteria causative of Whipple's disease, was analyzed to identify specific metabolic deficiencies. This evidenced the impossibility for the bacteria to synthesize a variety of amino acids. We used this information to design a comprehensive medium that allowed three established T. whipplei strains from culture with human cells and one new strain from a clinical sample to grow axenically, that is independently from any cellular host. Genomic information can, therefore, provide sufficient clues for designing cell-free media for fastidious and uncultured pathogens. In addition to breaking the rigid classification between "parasitic" and "free-living" microorganisms, this work can also be considered a first tangible and useful achievement of in silico "system" biology. The automatization of our approach constitutes a possible pathway towards the reification of the "virtual cell" concept. Methods to automatically generate qualitative Petri net models from genomic annotation are being explored. References: Lancet 362:447-9 (2003); Science 302, 19-20 (2003).