Bacterial DNA Repair and Mutagenesis
Bacteria have a remarkable capacity to thrive in adverse environments. Their adaptability relies on stress responses that provide temporary protection, for example by repairing cell damage or removing toxic chemicals. Such phenotypic adaptation offers cells a window of opportunity to evolve permanent stress resistance through genetic change. Failures to cure bacterial infections with antibiotics are often due to stress responses that promote bacterial survival as well as the evolution of drug resistance. Our lab seeks to understand how this works at the molecular level using a quantitative interdisciplinary approach. We focus on the mechanisms of DNA repair and mutagenesis, which are essential both for stress survival and for genetic change. A key aspect of our research is developing fluorescence microscopy techniques to visualise molecular events in real-time within living cells. We use super-resolution microscopy and single-molecule tracking to record the localization and movement of individual molecules such as DNA repair enzymes or transcription factors. To monitor the cellular responses to stress, we use microfluidic devices for imaging single cells. This allows us to decipher how molecular events inside cells determine long-term cell fates. Curiously, single-cell analysis revealed that bacterial phenotypes are variable even in a constant environment, a phenomenon that may be linked to stress survival. We discovered that mutation rates are also variable due to fluctuations in the expression of DNA repair proteins. These findings open fundamental questions about the mechanisms and regulation of mutagenesis, which we are now addressing using a range of novel microscopy and genetic approaches.
Uphoff Lab | Department of Biochemistry | University of Oxford

News
Amy Moores
February 2021
Welcome to postdoctoral scientist Amy who is focusing on microscopy development in our group.
Divya Choudhary
October 2020
Divya is a new DPhil student in our group and won an Indira Gandhi scholarship at Somerville College.
Chloe Cassaro
July 2020
Welcome to Chloe Cassaro who joins our group officially as a DPhil student having completed her successful DTP rotation project.
Victor Chen and Nicolas Aryanpour
July 2020
Congratulations to Victor Chen who completed an internship and his Part II Biochemistry research project, and Nicolas Aryanpour who had joined us for an ERASMUS internship as part of his Masters degree at UC Louvain! Farewell!
DNA-target search
February 2021
Our new article in Molecular Cell shows that the bacterial chromosome is crowded with non-specifically bound proteins. Transient non-specific DNA binding dominates the target search of bacterial DNA-binding proteins.
Lister Prize
August 2020
Our lab has been awarded a Lister Institute Research Prize for our work on DNA repair and mutagenesis in bacteria.
LexA and the SOS response
July 2020
New preprint on the regulation of the SOS response by LexA: Imaging LexA degradation in cells explains regulatory mechanisms and heterogeneity of the SOS response.
DNA organization - replication - segregation
July 2020
Interplay between chromosome organization and replication fosters non-random inheritance of genetic material. Preprint online: Non-random segregation of sister chromosomes by Escherichia coli MukBEF axial cores.
Review article in Biochemical Society Transactions
March 2020
Our views on the origins and consequences of "Bacterial phenotypic heterogeneity in DNA repair and mutagenesis" are now published!
Under the Lens
We are running a journal club with other groups at Oxford, where we take recent papers on Microbial Imaging "Under the Lens". This goes together with a new regular feature in Nature Reviews Microbiology. More details can be found here.