Skip to main content
Kent Academic Repository

Exploiting prokaryotic nucleotide excision repair as a novel antimicrobial target for combinatorial therapies in cancer patients

Bernacchia, Lorenzo (2023) Exploiting prokaryotic nucleotide excision repair as a novel antimicrobial target for combinatorial therapies in cancer patients. Doctor of Philosophy (PhD) thesis, University of Kent,. (doi:10.22024/UniKent/01.02.102412) (Access to this publication is currently restricted. You may be able to access a copy if URLs are provided) (KAR id:102412)

Language: English

Restricted to Repository staff only until August 2026.

Contact us about this Publication
[thumbnail of 229Bernacchia2023phd_corrected.pdf]
Official URL:


Infections are a group of pathologies which are increasing in severity due to the lack of new therapeutic approaches and the concomitant rise of antimicrobial resistance. This issue is particularly concerning in cancer patients who are often immunocompromised as a side effect of chemotherapy.

Most anticancer treatments target rapidly dividing cancerous cells but also hit immune system cells and bacteria. Bacteria, however, possess efficient DNA repair systems that allow them to escape otherwise lethal damage. In this thesis, we evaluated strategies to extend the cytotoxic activity of DNA-damaging agents to bacteria by inhibiting nucleotide excision repair (NER), a central prokaryotic DNA repair system responsible for recognising various damages.

We began our study with ATBC, the first effective NER inhibitor in mycobacteria, to understand its mechanism of action and molecular target. We confirmed its activity on Escherichia Coli and used in silico tools to predict its binding to UvrA, the first responder in the NER pathway. We then confirmed this activity in vitro by directly measuring UvrA's ATP turnover and its compromised DNA binding ability. Furthermore, we evaluated the compound's ability to inhibit the activity of the entire UvrABC complex through an incision assay. This data provided the rationale for moving forward in our study.

We designed two screening approaches to develop novel NER inhibitors to be used alongside the widely used anticancer drug cisplatin. We screened an FDA-approved drug library composed of ~3000 compounds in combination with cisplatin as well as virtually screening ~120000 compounds directly against UvrA ATP-binding pockets. The hits that emerged from this approach were subjected to a wide range of in vivo, biochemical, in silico and single molecule studies to confirm NER as a molecular target and to elucidate their mechanism of action.

We highlighted 8 principal candidates, among which 5 showed increased antibacterial activity against a clinically relevant E. coli strain responsible for multidrug-resistant infections. In doing so, we have taken the first step in developing a novel antimicrobial approach that could represent a valuable tool in fighting co-infections in cancer patients.

Item Type: Thesis (Doctor of Philosophy (PhD))
Thesis advisor: Kad, Neil
DOI/Identification number: 10.22024/UniKent/01.02.102412
Uncontrolled keywords: DNA repair; drug discovery; antimicrobial; nucleotide excision repair; antimicrobial resistance; cancer; adjuvants; virtual screening; UvrA; ATPase inhibitors
Subjects: Q Science
Divisions: Divisions > Division of Natural Sciences > Biosciences
SWORD Depositor: System Moodle
Depositing User: System Moodle
Date Deposited: 11 Aug 2023 10:10 UTC
Last Modified: 15 Aug 2023 08:47 UTC
Resource URI: (The current URI for this page, for reference purposes)

University of Kent Author Information

Bernacchia, Lorenzo.

Creator's ORCID:
CReDIT Contributor Roles:
  • Depositors only (login required):

Total unique views for this document in KAR since July 2020. For more details click on the image.