Research: Enterococcus faecalis is a Gram-positive pathobiont that infects many distinct body sites due to its antibiotic resistance, environmental tolerance, and biofilm formation.
Protein-based regulation of these phenotypes is highly studied, but uncharacterized
transcription factors and sigma factors remain. Further, very little is known about the
role of noncoding RNAs (ncRNAs) in E. faecalis gene regulation. The E. faecalis
strain OG1RF is a widely-used model for studying the E. faecalis core genome, and
genetic tools such as transposon libraries in this strain facilitate identification of
uncharacterized gene functions. I identified 121 ncRNAs predicted in E. faecalis V583
that have sequence homology in OG1RF. I found transposon insertion mutants in our
OG1RF Tn library for 50 of the 121 predicted ncRNAs, two hypothetical transcription
factors, and a hypothetical sigma factor. I arrayed these Tn insertion mutants and am
screening growth and biofilm formation in this library across 13 conditions at two
timepoints to link these regulatory factors to biologically-relevant phenotypes. I will
determine regulons and mechanisms of action for high-priority ncRNAs and regulatory
proteins to broaden our understanding of E. faecalis gene regulation. This will widen
the arsenal of potential drug targets for treating infections with this highly antibiotic-
resistant bacterium.
