Host: Professor Arnab Pain

Abstract:
The gut microbiota of healthy individuals is commonly dominated by the Bacteroidota bacterial phylum. Within this phylum, members of the Bacteroidaceae and Prevotellaceae family tend to exclusively predominate the microbiomes of populations with industrialized and traditional lifestyles, respectively. These predominance patterns are mainly attributed to distinct diets and are associated with ambiguous health outcomes. Prevotellaceae predominance in the microbiota has been associated with healthy lifestyles and improved health outcomes, whereas Bacteroidaceae predominance is associated with diets high in processed foods and animal fat. Interrogating experimentally how such microbiota compositional patterns are shaped beyond association studies is critical for elucidating microbiome health biomarkers. 

How these different microbiota configurations are shaped and how they interact with pathogens and different dietary patterns, remains largely unexplored experimentally. Through synthetic community design, anaerobic microbiology, gnotobiotics, and metagenomics analysis, we elucidate the principles that govern major microbiota signatures in human populations. We focus on niche interactions between members of the Bacteroidaceae and Prevotellaceae families and systematically assess how dietary components influence interactions between these two bacterial families. Together, our studies provide new insights into the long-standing question of what drives major human microbiota configurations. Given these signatures, our work explores how infections and environmental signals drive the evolution of the major inhabitants of the human gut leaving lasting and functional signatures on the gut microbiota.

Bio:
Dr. Tawk trained in Molecular and Cellular Biology at the American University of Beirut, Lebanon, and completed her PhD in Infection and Immunity in the laboratory of Prof. Jörg Vogel at the University of Würzburg, Germany. She subsequently conducted postdoctoral research with Prof. Andrew Goodman at Yale University, where she developed approaches combining anaerobic microbiology and genetics, and gnotobiotic mouse models to study how infection impacts gut commensals. She then joined the Helmholtz Centre for Infection Research in Germany, where, in the laboratory of Prof. Till Strowig, she investigated the interface between gut microbes and immunity and developed synthetic microbial communities to study microbiota assembly. She did a research stay at EMBL with Prof. Nassos Typas, where she applied systems biology approaches to investigate how dietary factors shape synthetic community assembly.

Dr. Tawk is a Ramón y Cajal tenure-track awardee and Group Leader at the IrsiCaixa Infection Research Institute in Barcelona. Her research combines synthetic microbial community design, anaerobic microbiology and genetics, and infection biology to understand how gut microbiota configurations assemble and respond to pathogens.