Poster Presentation: Distinct evolutionary trajectories in the Escherichia coli pangenome

Abstract

Escherichia coli is a diverse species spanning both common commensals of humans and animals and clinically important, major global pathogens. Pangenomics can facilitate the understanding of the diversity within this species. Previous work on ST131 found allelic diversity in metabolism and colonisation genes that was linked to multidrug resistance. To develop this work further, we have examined E. coli as a whole species on a lineage-by-lineage basis. 20,577 genomes were used to construct pangenomes for 21 distinct E. coli sequence types. We have identified sequence types enriched in metabolism genes, lineage-specific differences in core metabolic profiles, and lineage-specific alleles that may shed light on sequence type-specific metabolic adaptions that appear to evolve independently of phylogeny. These findings also provide evidence for differential evolution of metabolism genes. Our results suggest that selection and evolution of lineage-specific E. coli pangenomes may be happening in a non-phylogenetic manner and that sequence types are distinct in different ways. Further understanding of how these lineages differ will be key in future research to manipulate the abilities of specific E. coli lineages in their relevant environments.

Elizabeth A. Cummins

Postdoctoral Researcher

My research interests include microbial genomics, pangenomes and AMR.