Characterisation_of_anaerobic_E__coli_K12_by_Tradis

Escherichia coli is an important member of the gut microbiota of humans and other animals. E. coli K-12 strain MG1655 has been widely used as a model for studying colonization of the mouse gut. However studies have been limited in terms of the number of mutants tested. Therefore, we propose to use transposon insertion sequencing (TraDIS) to carry out the first comprehensive genetic analysis of E. coli fitness under conditions relevant to colonization of the mammalian gut. The mammalian gut is generally considered to be an anaerobic environment. Recent work by several groups has shown that the proportion of E. coli in the gut microbiome increases significantly during inflammation, and it has been suggested that this is due to the ability of E. coli to use host-derived nitrate (produced during inflammation) as an alternative electron acceptor. In this study we have grown a high-density E. coli mutant library grown under anaerobic conditions with several different carbon sources, with or without the addition of nitrate. In this way we aim to identify genes that contribute to the fitness of E. coli (and other Enterobacteriaceae) in the inflamed gut.