... understanding life in molecular detail

Dr Robin Bon

Chemical Biology, Structural Biology, Ion Channel Pharmacology, Mass Spectrometry, Organic Chemistry


We use chemical, biochemical and biophysical approaches to understand molecular mechanisms underlying (cardiovascular) health/disease and the effects of bioactive small molecules. For example, we use site-directed mutagenesis, cellular assays, new photoaffinity probes, mass spectrometry and cryo-electron microscopy to develop a detailed understanding of interactions between bioactive small molecules and their target proteins. In addition, we develop novel chemical tools for mass spectrometry and biosensing. The group has lab space in the School of Chemistry (organic and analytical chemistry) and in the LIGHT laboratories (mammalian cell culture and biochemistry).

Current major projects include:
  • Chemical and structural biology of TRP ion channels
  • Light-induced protein labelling in vitro and in cells
  • Ionisation enhancers for mass spectrometry of peptides/carbohydrates
  • Modification of surfaces and nanoparticles for biosensing/imaging
  • Target identification and validation

 

Structural insight into modulation of TRPC1/4/5 channels

Transient Receptor Potential (TRP) proteins, which include the TRPM, TRPV, TRPA and TRPC subtypes, form tetrameric, non-selective cation channels permeable by Na+ and Ca2+. For all 28 mammalian TRP proteins, four monomers are needed to form a functional ion channel, and channels may consist of homomers or heteromers of subunits, each with their own characteristics and functions. Our research focuses on homomeric and heteromeric channels formed by TRPC1, TRPC4 and TRPC5. Their implication in various human disease states has led these channels to emerge as potential therapeutic targets. However, little is known about the exact composition of TRPC1/4/5 tetramers in different tissues, and the lack of information about binding modes of channel modulators prevents the design of tetramer-specific activators and inhibitors. In this project, we use molecular biology, photoaffinity probes, mass spectrometry and cryo-electron microscopy to unravel the interactions between specific TRPC1/4/5 subunits, between TRPC1/4/5 channels and small-molecule modulators, and between TRPC1/4/5 channels and lipids.

PhD students and postdocs involved (funder): Aisling Minard (BBSRC/AstraZeneca), Isabelle Pickles (Wellcome Trust), Dr Claudia Bauer (BBSRC), Dr David Wright (BBSRC)

Main collaborators: Prof. David Beech (Leeds Institute of Cardiovascular and Metabolic Medicine), Dr Stephen Muench (School of Biomedical Sciences), Prof. Frank Sobott (School of Molecular and Cellular Biology), Dr Megan Wright and Dr Stuart Warriner (both School of Chemistry), Prof. Mathias Christmann (Freie Universität Berlin, Germany), Prof. Katsuhiko Muraki (Aichi Gakuin University, Kusumoto, Japan).

 

Novel ionisation enhancers for mass spectrometry of biological samples

Label-assisted laser desorption/ionisation mass spectrometry (LALDI-MS) is a novel and powerful tool for the selective analysis of labelled species by mass spectrometry. LALDI-MS is carried out in a similar manner to matrix-assisted laser desorption/ionisation mass spectroscopy (MALDI-MS), however the external matrix component of MALDI has been replaced with a laser desorption/ionisation-enhancing label. Through this development, LALDI-MS has gained several benefits over MALDI-MS, eradicating concerns over optimum analyte–matrix pairings and allowing analysis to be performed directly against a complex background without the need for purification. We develop novel, water-soluble, LALDI tags for in situ labelling of analytes in complex samples. The technology allows us to directly analyse biological samples without the need for purification.

PhD student involved (funder): Jacob Hauser (University Research Scholarship)

Main collaborators: Prof. Jane Thomas-Oates (Centre of Excellence in Mass Spectrometry, University of York), Dr Stuart Warriner and Dr Robert Menzel (both School of Chemistry)

 

Understanding the mode-of-action of a bioactive small molecule

The small molecule KHS101 induces a catastrophic metabolic phenotype – leading to lethal cellular degradation – in a range of patient-derived glioblastoma multiforme (GBM) cells, but not in healthy patient-derived brain cells. In addition, the molecule also significantly reduces intracranial GBM xenograft tumour growth upon systemic administration, without discernible side effects. Through a major interdisciplinary collaboration that involved chemical proteomics, global proteomics, transcriptomics, metabolomics, and assays in vitro, in cells and in animal tissues, the mitochondrial chaperonin HSPD1 was identified and validated as the relevant target of KHS101 in GBM cells (www.biorxiv.org/content/early/2017/10/18/205203). We are currently using a combination of photoaffinity labelling, mass spectrometry and cryo-electron microscopy to develop a deeper understanding of the molecular interactions between mtHSPD1 and KHS101.

(Former) PhD students involved (funder): Dr Hester Beard (EPSRC DTA), David Klebl (Wellcome Trust)

Main collaborators: Dr Heiko Wurdak (Leeds Institute of Cancer & Pathology), Dr Lee Roberts (Leeds Institute of Cardiovascular and Metabolic Medicine), Prof. Neil Ranson (School of School of Molecular and Cellular Biology), Prof. Frank Sobott (School of Molecular and Cellular Biology), Dr Stephen Muench (School of Biomedical Sciences), Dr Shoutian Zhu (formerly California Institute for Biomedical Research), Prof. Jason Gestwicki (UCSF)

 

Catalytic tag transfer reagents for traceless protein labelling

Protein-protein interactions (PPIs) mediate a large number of important processes within the human body. As such, their study is of huge importance in the understanding of diseases and the development of pharmaceuticals. In order to elucidate the structure and function of specific proteins, it is important that they can be studied within their native cellular environment. The aim of this project is to develop a set of modular chemical tools to study protein-protein interactions (PPIs) formed by endogenous proteins, ultimately applicable for use in cellular studies. So far, we have developed tag transfer reagents consisting of a protein ligand linked to a transition metal catalysts, which allow selective, traceless, light-induced protein labelling with sub-stoichiometric amounts of reagent.  

Former PhD student involved (funder): Dr Hester Beard (EPSRC DTA)

Main collaborators: Prof. Andrew Wilson (School of Chemistry), Dr Andrew Macdonald (School of School of Molecular and Cellular Biology)

Detailed research programme                  Close ▲
RSB.jpg

Lecturer in Cardiovascular Chemistry
BSc PhD (Amsterdam)
Thieme Chemistry Journal Award 2012, Alexander von Humboldt Fellowship 2007-2009, Prof. Dr. H.J. Backer Prize 2007

Senior Translational Research Fellow (University of Leeds) 2009-2015
Postdoctoral Research Fellow (MPI Dortmund) 2006-2009


LIGHT building, level 7
School of Biomedical Sciences
01133430785
r.bon@leeds.ac.uk

https://twitter.com/rsbon_lab

Selected Publications

  1. Minard, A.; Bauer, C.C.; Wright, D.J.; Rubaiy, H.N.; Muraki, K.; Beech, D.J.; *Bon, R.S. “Remarkable Progress with Small-Molecule Modulation of TRPC1/4/5 Channels: Implications for Understanding the Channels in Health and Disease.Cells 2018, 6, pii: E52.

  2. Rubaiy, H.N.; Ludlow, M.J.; Henrot, M.; Gaunt, H.J.; Miteva, K.; Cheung, S.Y.; Tanahashi, Y.; Hamzah, N.; Musialowski, K.E.; Blythe, N.M.; Appleby, H.L.; Bailey, M.A.; McKeown, L.; Taylor, R.; Foster, R.; Waldmann, H.; Nussbaumer, P.; Christmann, M.; Bon, R.S.; Muraki, K.; *Beech, D.J. “Picomolar, selective, and subtype-specific small-molecule inhibition of TRPC1/4/5 channels.The Journal of Biological Chemistry 2017, 292, 8158–8173.

  3. Naylor, J.; Minard, A.; Gaunt, H.J.; Amer, M.S; Wilson, L.A.; Migliore, M.; Cheung, S.Y.; Rubaiy, H.N.; Blythe, N.M.; Musialowski, K.E.; Ludlow, M.J.; Evans, W.D.; Green, B.L.; Yang, H.; You, Y.; Li, J.; Fishwick, C.W.G.; Muraki, K.; *Beech, D.J.; *Bon, R.S. “Natural and synthetic flavonoid modulation of TRPC5 channels.British Journal of Pharmacology 2016, 173, 562–574.

  4. Polson, E.S.; Kuchler, V.B.; Abbosh, C.; Ross, E.M.; Mathew, R.K.; Beard, H.A.; Chuntharpursat-Bon, E.; Da Silva, B.; Shao, H.; Patel, A.; Davies, A.J.; Droop, A.; Griffiths, H.B.S.; Chumas, P.; Short, S.C.; Lorger, M.; Gestwicki, J.; Roberts, L.D.; Bon, R.S.; Allison, S.J.; Zhu, S.; Markowetz, F.; *Wurdak, H. “The small molecule KHS101 induces bioenergetic dysfunction in glioblastoma cells through inhibition of mitochondrial HSPD1.bioRxiv 2017, doi.org/10.1101/205203.