Dr Melissa Webby

Supervisor Details

Contact Details

Department of Biochemistry, University of Oxford

Scientific Background

Research Interests

Melissa is fascinated by protein structure and function. Following completion of her PhD at the University of Auckland, New Zealand (2018), Melissa took up a postdoc position in the UK under the supervision of Prof. Colin Kleanthous. Within the Kleanthous group her research has combined classical protein biochemistry with cryo-electron microscopy to understand how protein toxins cross the cell envelope of Gram-negative bacteria.

Her current research is centred around fundamental questions relating to how outer membrane proteins of Gram-negative bacteria are organised and how force is transduced across the cell envelope through the bacterial Ton-system.

Research Groups

Kleanthous Lab

Supervision Style

In three words or phrases: supportive, empowering, structured.

Provision of Training

Hands on training in the lab from myself or other lab members, will be provided at the start of the project to equip you with the skills you need to drive your independent research. I am a huge advocate for teaching others helps with learning. I am also very willing to help support your attendance at training courses provided by the University or wider, that help you to develop both lab and research skills e.g. scientific writing workshops.

Progression Monitoring and Management

The lab will have fortnightly lab meetings that everyone shares at and we exchange ideas and practical support. We will also have one-to-one meetings every other week to discuss the project in more detail. Monthly lab reports (2 pages max) will provide a basis for project check in and tracking. We will meet once a year to discuss personal development and set plans to help achieve your research goals.

Communication

I am available via email, and I have an open-door policy during work hours. I will be around for an informal coffee or break or hallway catch up during my work hours.

PhD Students can expect scheduled meetings with me:

In a group meeting

At least once per week

In year 1 of PhD study

At least once per fortnight

In year 2 of PhD study

At least once per fortnight

In year 3 of PhD study

At least once per month

These meetings will be face to face. I am usually contactable for an instant response every working day.

Work Patterns

Certain tasks in my lab need to occur at set times, and students need to be able to commit to a rota/timetable shared with other members of the team.

Notice Period for Feedback

I need at least 2 weeks' notice to provide feedback on written work of up to 5000 words.

MIBTP Project Details

Current Projects (2025-26)

Primary supervisor for:

Deciphering the interplay between biogenesis and maintenance of the bacterial cell envelope

See the PhD Opportunities section to see if this project is currently open for applications via MIBTP.

Please Note: The main page lists projects via BBSRC Research Theme(s) quoted and then relevant Topic(s).

Deciphering the interplay between biogenesis and maintenance of the bacterial cell envelope

Secondary Supervisor(s): Professor David Roper

University of Registration: University of Warwick

BBSRC Strategic Research Priority: Understanding the Rules of Life (Microbiology, Structural Biology)

Project Outline

Antimicrobial resistance in Gram-negative bacteria poses a major global health threat as evidenced by these species dominating the world health organisation’s critical list. These bacteria are responsible for a multitude of infections including, pneumonia, urinary tract infections, meningitis, and wound infections. A fundamental mechanism driving resistance in Gram-negative bacteria is the impermeability conferred by their robust cell envelope, which comprises an asymmetric proteolipid outer membrane, a peptidoglycan layer, and a cytoplasmic inner membrane. (Figure 1).

The maintenance of this multi-layered envelope is essential for bacterial viability. Key biological processes, such as gliding motility, antibiotic efflux, lipid secretion, membrane stabilisation, and nutrient import, are facilitated by dynamic multiprotein complexes that bridge these layers. These protein interactions create a critical linkage between the outer and inner membranes, enabling the coordination necessary for cellular function. Despite the importance of these envelope complexes, the molecular details of their assembly and the coordination of their roles remain poorly understood.

The lab is focused on elucidating the assembly and interactions of trans-envelope complexes, with a particular emphasis on understanding how these multiprotein systems synthesise and maintain the envelope structure during bacterial division. This cooperative functionality is crucial for preventing structural defects as cells undergo division. Specifically, this project will investigate how stabilisation of the outer membrane by the Tol-Pal complex^1-3 is coordinated with synthesis of the peptidoglycan layer by PG-synthase complexes.⁴ By addressing this aspect of envelope maintenance, we aim to reveal insights that could inform the development of drugs designed to destabilise the bacterial envelope.

To achieve these goals, we employ a suite of advanced methodologies, including cryo-electron tomography and fluorescence microscopy for cellular studies, complemented by structural, biophysical, and biochemical techniques to uncover the underlying molecular mechanisms. This comprehensive approach allows us to build a detailed understanding of these essential processes.

The Webby lab offers extensive expertise in cryo-electron microscopy and the study of the Tol-Pal system, while the Roper lab provides world-renowned knowledge in peptidoglycan synthesis and structural analysis. Our collaborative and research-driven environment supports students in developing their projects and pursuing their specific interests. Additionally, our lab maintains strong collaborative ties with other leading research institutions, fostering a network of learning and discovery.

This project is ideal for students passionate about microbiology, antibiotic resistance, and biochemistry. Prospective students are encouraged to reach out for further discussion or to explore mini project opportunities (melissa.webby@bioch.ox.ac.uk).