Submission Date


Document Type

Paper- Restricted to Campus Access


Biochemistry & Molecular Biology

Faculty Mentor

Anthony Lobo

Second Faculty Mentor

Mark Ellison

Student Contributor

Elizabeth McKenna

Second Student Contributor

Cassandra Burke


Presented during the 23rd Annual Summer Fellows Symposium, July 23, 2021 at Ursinus College.

Project Description

Bacteria can acquire resistance to antimicrobials in a multitude of ways, causing antibiotic resistance to be a growing public health concern. This research coincides with Dr. Ellison’s group with the production of antibiotic-conjugated nanomaterials to overcome bacterial resistance. The goal of this project is to find strains with specific resistance mechanisms to understand the interaction between antibiotic-conjugated nanomaterials and the bacterial strains themselves. These mechanisms include efflux pumps, target site mutations, target blockers and antibiotic modifying enzymes. Our hypothesis states that nanotube-conjugated antibiotics will be able to overcome the efflux pump resistance mechanism through creating steric hindrance that prevents the pump from removing them. We tested twelve CRCs, sixteen CREs, and two control strains- E. faecalis and TOP10 E. coli. These strains were tested for level of resistance through minimum inhibitory concentration assays, which were then analyzed against genes discovered with Polymerase Chain Reaction (PCR). Plasmid-borne resistance genes were examined from these strains and are being transformed into laboratory strains of E. coli, with well-characterized genomes. CRC strains and TOP10 were found to have efflux pump acrA, but not oqxAB. Some CREs were found to have msrC, an efflux pump implicated in clarithromycin resistance. All strains were tested with an uncoupler to determine the presence of a proton-powered efflux pump. Understanding the basis of our resistant strains will aid us in future design of antibiotic conjugated nanomaterials and apply it to strains with similar mechanisms.


Available to Ursinus community only.