부산대학교 도서관

Metabolomics, the comprehensive high throughput characterization of small-molecule metabolites found in biological materials, has the potential to provide insights into the pathogenesis of disease states and to lead to the detection of new disease biomarkers. Although Escherichia coli strains are generally recognized as safe and rarely cause disease, the shiga toxin-producing Escherichia coli O157:H7 is a severe enteropathogen that causes outbreaks of hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS). The nematode Caenorhabditis elegans has been used as a model to study bacterial and fungal pathogenesis and innate immunity. Therefore, C. elegans can be useful as a host for the identification of metabolites showing the pathogenicity of E. coli O157:H7 as well as the elucidation of metabolic pathways affected by E. coli O157:H7. In this study, C. elegans was treated with the non-pathogenic E. coli OP50 or the pathogenic E. coli O157:H7 strain and their metabolites were analyzed by gas chromatography-time of flight mass spectrometry (GC-TOF MS). Multivariate analysis techniques, such as partial least squares discriminant analysis (PLS-DA) and hierarchical clustering analysis were used to classify the samples according to their metabolite characteristics. Overall, 103 metabolites were identified and PLS-DA revealed that metabolite profiling patterns after the treatment of C. elegans with a pathogenic E. coli compared to the non-pathogenic strain were well separated. Especially, the sugar metabolism and the amino acid bio synthesis in C. elegans were found to be critical for the life span under E. coli O157:H7 in comparison with C. elegans treated with E. coli OP50. Therefore, the global metabolic analysis based on GC-TOF MS is useful for the understanding of the mechanisms of bacterial pathogenesis.