Titel: A metagenomics tool to investigate spirochete diversity in different anatomical and ecological sites
Art: Abstractautor
Session: Workshop 03
Diagnostic Microbiology (StAG DV)

Referent: Luisa Hallmaier-Wacker (Göttingen)

Abstract - Text

Spirochetes, a morphologically distinct phylum of bacteria, range from pathogenic (e.g., Treponema pallidum) to symbiotic (e.g., Sphaerochaeta coccoides) to free-living (e.g., Exilispira thermophile) organisms. The ability of spirochetes to inhabit vastly different anatomical and ecological sites is remarkable and indicates the diversity of bacteria that make up this phylum. To investigate the evolution and diversity of spirochetes in biological samples, we developed a metagenomics sequencing approach that enables the characterization of spirochetes from different ecological sites. In-silico, we determined that by sequencing different regions of the 16S rRNA gene (e.g., variable region 4), a variety of spirochetes can be detected in biological samples. The in-silico results indicate that the resolution of the different species of Treponema is especially good as more than 20 species (97% similarity threshold) can be differentiated using a single variable region. To validate the in-silico results, we created a bacterial mock community by mixing together 16 species of known spirochetes (e.g. Treponema pallidum). We discuss the results of the validation experiments and present the areas of applications of the metagenomics techniques. To show the applicability of the NGS tool for clinical samples, we present data from a recent investigation of oral spirochetes of captive and wild non-human primates (NHPs).  We discuss the benefits and limitations of the metagenomics approach in identifying novel species and uncovering the diversity of spirochetes. Our understanding of the biology of spirochete will develop as we understand more about the diversity of species and their ability to inhabit and adapt to different ecological landscapes.