Life Sciences Commons^™

Towards More Complete Metagenomic Analyses Through Circularized Genomes And Conjugative Elements, Benjamin R. Joris

Electronic Thesis and Dissertation Repository

Advancements in sequencing technologies have revolutionized biological sciences and led to the emergence of a number of fields of research. One such field of research is metagenomics, which is the study of the genomic content of complex communities of bacteria. The goal of this thesis was to contribute computational methodology that can maximize the data generated in these studies and to apply these protocols human and environmental metagenomic samples.

Standard metagenomic analyses include a step for binning of assembled contigs, which has previously been shown to exclude mobile genetic elements, and I demonstrated that this phenomenon extends to all conjugative …

Dynamics Of The Soil Microbiome In Ginseng Gardens, Megan E. Lambert

Electronic Thesis and Dissertation Repository

Ginseng Replant Disease (GRD) is a syndrome in which ginseng cannot be cultivated in soil previously used to grow ginseng. Since GRD can persist for decades, it severely impacts the Ontario ginseng industry. To better understand the origin of GRD, the impact of ginseng cultivation on the soil microbiome was investigated in bulk soil of three newly planted ginseng gardens in Ontario, from seeding through two years of cultivation. While specific trends in species richness, diversity and composition were unclear, PERMANOVA analyses confirmed that they changed over time. Known GRD-related pathogens, including Ilyonectria mors-panacis and Fusarium oxysporum, were detected in …

Clinical And Mechanistic Insights Into Novel Probiotic Functions And Formulations, Jordan Bisanz

Electronic Thesis and Dissertation Repository

Using a combination of hypothesis and discovery based approaches, the goal of this thesis was to better describe novel probiotic functions and their mechanisms while striving to better understand the effect of formulation on Bifidobacterium animalis subsp. lactis, Lactobacillus paracasei and L. rhamnosus.

Using RNA-Seq, a bacterial metatranscriptome analysis of a commonly consumed probiotic yogurt showed that the organisms adapted to storage time and flavor additions. This led to the discovery that in addition to the probiotic health benefits, members of the L. casei group (L. rhamnosus and L. paracasei) produce volatile sulfur compounds mediated by a novel …