Abstract 2089 Competition assays of naturally derived missense mutants reveal a spectrum of functionally important amino acid residues of RsmE
Year: 2024
Type: conference-abstract
Abstract: Laboratory colonies of the bacterium Pseudomonas fluorescens Pf0-1 naturally produce mutants with diverse altered sequences in the rsmE gene. RsmE is a posttranscriptional regulator that represses the production of extracellular secretions by inhibitive mRNA binding. Mutants in which RsmE has lost repressive function gain a spatial advantage against the wildtype via production of extracellular secretions. Such secretions are utilized by diverse bacterial species to form structured communities, referred to as biofilms, that greatly resist antibiotics and the immune system to manifest chronic infections. Our collection of naturally derived missense rsmE mutants provides a unique opportunity to assess the functional significance of the altered amino acid residues. We hypothesize that RsmE's functionality is differentially altered depending on the specific changes in its primary sequence. To test this hypothesis, select rsmE missense mutants were competed against each other in a round-robin tournament format to assess their relative competitive advantage. A spectrum of relative fitness values was observed, confirming that specific amino acid residues uniquely contribute to RsmE's function. Moving forward, we will test all missense mutants to comprehensively categorize them across a single competitive scale, and select isolates from each category will be utilized to characterize differential mRNA binding and secretion production. This research is supported by the National Institute of General Medical Sciences (NIH 1R15GM132856).
Source: Journal of Biological Chemistry
Authors: Austin Summers, Meghan Wells, Wook Kim
Institution: Duquesne University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,800
OpenAlex ID: W4393166703