Dynamic genetic adaptation of Bacteroides thetaiotaomicron during murine gut colonization

• DOI: 10.1016/j.celrep.2023.113009
• Publication Date: 2023-08-21T11:40:16Z
• Authors: Megan S. Kennedy; Manjing Zhang; Orlando DeLeon; Jacie Bissell; Florian Trigodet; Karen Lolans; Sara Temelkova; Katherine T. Carroll; Aretha Fiebig; Adam Deutschbauer; Ashley M. Sidebottom; Joash Lake; Chris Henry; Phoebe A. Rice; Joy Bergelson; Eugene B. Chang
• Keywords: Bacteroides thetaiotaomicron; Host adaptation

To understand how a bacterium ultimately succeeds or fails in adapting to new host, it is essential assess the temporal dynamics of its fitness over course colonization. Here, we introduce human-derived commensal organism, Bacteroides thetaiotaomicron (Bt), into guts germ-free mice determine whether and genetic requirements for colonization shift time. Combining high-throughput functional genetics assay transcriptomics, find that gene usage changes drastically during first days colonization, shifting from high expression amino acid biosynthesis genes broad upregulation diverse polysaccharide utilization loci. Within week, metabolism becomes centered around predominant dietary oligosaccharide, these are largely sustained through 6 weeks Spontaneous mutations wild-type Bt also evolve this locus. These findings highlight importance considering developing more effective microbiome-based therapies.