Research Associate (Bioenergetics and Single-Molecule Biophysics) in Sheffield

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Overview

We are seeking a talented and motivated Research Associate to join Professor Matt Johnson's group in the School of Biosciences to investigate how bioenergetic supercomplexes promote electron transfer in respiration and photosynthesis. The role is funded by a Biotechnology and Biological Sciences Research Council (BBSRC) responsive mode grant for three years, commencing in October 2026.

A central puzzle in bioenergetics is why electron transfer (ET) complexes cluster into larger supercomplexes within the membranes of mitochondria, chloroplasts, and bacteria. Building on our recently developed single-molecule atomic force microscopy (smAFM) approach, this project will test the hypothesis that supercomplexes enhance ET by promoting the formation of transient encounter complexes between soluble electron carrier proteins and their cognate membrane integral complexes. The work spans bacterial, mitochondrial, and chloroplast systems and combines smAFM with complementary biophysical methods (mass photometry, microscale thermophoresis, spectroscopy), cryo-electron microscopy, and the engineering of artificial supercomplexes via CRISPR-Cas9 in Chlamydomonas.

You will work within a vibrant research environment that includes the Imagine: Imaging Life facility, world-class controlled environment plant and algal growth facilities, and an active community of researchers in photosynthesis, bacterial bioenergetics, and structural biology. You will also collaborate with leading international partners, providing excellent opportunities for career development.

Main duties and responsibilities

• Design, execute, and analyse single-molecule atomic force microscopy (smAFM) experiments to quantify the binding probabilities, unbinding forces, and turnover rates of electron carrier proteins on isolated and supercomplex forms of bacterial, mitochondrial, and chloroplast electron transfer complexes.
• Purify membrane protein supercomplexes and their components from yeast mitochondria, Pseudomonas aeruginosa, spinach chloroplasts, and Chlamydomonas thylakoids, including via collaborations with international partners.
• Apply complementary biophysical methods, including mass photometry, microscale thermophoresis, and absorption and fluorescence spectroscopy, to characterise protein-protein interactions and electron transfer kinetics.
• Design and generate site-directed mutants of supernumerary subunits implicated in encounter complex formation and characterise their effects on binding and turnover.
• Engineer artificial supercomplexes in Chlamydomonas using CRISPR-Cas9, including the construction and validation of chimeric gene fusions and the purification biophysical and structural (Cryo-EM) characterisation of the resulting complexes.
• Liaise with collaborators conducting molecular and Brownian dynamics simulations to translate computational predictions into testable experimental hypotheses and vice versa.
• Disseminate research outputs through publications in international peer-reviewed journals, oral and poster presentations at national and international conferences, and contributions to public engagement activities.
• Contribute to the day-to-day running of the laboratory, including assisting with the training and supervision of postgraduate and undergraduate students.
• Contribute to grant reporting and to the preparation of further funding applications, including Researchfish submissions to the BBSRC.
• Maintain accurate, contemporaneous records of experimental data in line with good research practice and the University's research data management policy.
• Carry out other duties, commensurate with the grade and remit of the post.

Person Specification

Our diverse community of staff and students recognises the unique abilities, backgrounds, and beliefs of all. We foster a culture where everyone feels they belong and is respected. Even if your past experience does not match perfectly with this role's criteria, your contribution is valuable, and we encourage you to apply. Please ensure that you reference the application criteria in the application statement when you apply.

• PhD (or be close to completion / have equivalent postdoctoral work experience) in biochemistry, biophysics, structural biology, plant sciences, microbiology, or a closely related discipline.
• Substantial practical experience in protein biochemistry, including the purification and biochemical characterisation of membrane proteins or large multi‑subunit protein complexes.
• Experience of one or more biophysical methods for quantifying protein‑protein interactions, for example atomic force microscopy, mass photometry, microscale thermophoresis, surface plasmon resonance, or fluorescence‑based techniques.
• Experience of cryo‑electron microscopy.
• Excellent written and verbal communication skills, including the ability to present research clearly to specialist and non‑specialist audiences.
• A strong track record of research excellence relative to career stage, evidenced by first‑author publications in international peer‑reviewed journals.
• Experience of single‑molecule biophysics (for example smAFM, optical tweezers, single‑molecule fluorescence) and/or of research on photosynthetic or respiratory electron transfer complexes.
• Experience of molecular genetics approaches in algal, microbial, or plant systems, including the design and implementation of CRISPR‑Cas9 gene editing strategies.
• Demonstrable ability to plan, prioritise, and deliver research projects independently while contributing constructively to a collaborative team.
• Capacity to engage productively with national and international collaborators, including a willingness to travel for project meetings and short research visits.
• A commitment to inclusive working practices and to supporting the development of colleagues and students.

Further Information

Grade: 7
Salary: £38,784 - £43,482 per annum
Work arrangement: Full-time
Duration: Fixed-term for 3 years from November 2026
Line manager: Professor of Biochemistry
Direct reports: None
Right to work in the UK: If you do not currently hold the right to work in the UK, you can find more information here to help determine your visa eligibility.

Closing Date: 06/09/2026

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