Discipline: Biological Sciences
Kennedi Weston - University of Arkansas at Pine Bluff
Co-Author(s): Steven L.Foley- U.S. Food and Drug Administration-NCTR Ashlyn Carlton- University of Arkansas at Pine Bluff Yasser Sanad- University of Arkansas at Pine Bluff Bijay Khajanchi-U.S. Food and Drug Administration-NCTR Nesreen Aljahdali- U.S. Food and Drug Administration-NCTR Jing Han - U.S. Food and Drug Administration-NCTR
Many members of the Enterobacteriaceae carry plasmids such as incompatibility group (Inc) I1 plasmids that encode virulence and antimicrobial resistance that allow strains to survive in diverse conditions. Carriage of plasmids can lead to increased fitness costs, which is evidenced by diminished growth rates; however, the cost associated with IncI1 plasmids, alone or in combination with additional plasmids on Escherichia coli. Twenty-two transconjugants strains were developed by transferring plasmids from Salmonella into E.coli J53. IncI1 plasmids were typed by multilocus sequence typing (pMLST) and transconjugants were evaluated by seeding four wells of a 96-well microtiter plate with each strain and the plates were incubated at 37°C for 18 hr. in a Spectramax 384 Plus plate reader. Absorbance reading at 600 nm were taken every 30 min and exported to Microsoft Excel for analyses, with each set of experiments repeated. Results: Of the transconjugants, 12 strains carried the IncI1 plasmid alone, 10 strains also carried an IncA/C plasmid. pMLST indicated that there were 10 different sequence types, with ST26 being most common (n=9). The strains with growth rate higher than E.coli J53 carried both IncI1 and A/C plasmids, while those with the lowest growth rates had only the IncI1 plasmid. This study assessed the impact of plasmid carriage. Interestingly, some transconjugants carrying both IncI1 and A/C plasmids had a fitness benefit, while those with the highest fitness cost carried only IncI1 plasmids.
Funder Acknowledgement(s): This project was supported in part by an appointment to the Research Participation Program at the U.S. Food and Drug Administration administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and the U.S. Food and Drug Administration.
Faculty Advisor: Anissa Buckner, firstname.lastname@example.org
Role: I gained a further understanding of plasmid genetics and plasmid biology, developed skills to evaluate the impact of antimicrobial exposure on plasmid transfer, and develoed additional skills for presenting scientific resultsthrough written and oral presentations.