A5054099930- Lipid Membrane Structure and Behavior
- Mass Spectrometry Techniques and Applications
- Metabolomics and Mass Spectrometry Studies
- X-ray Diffraction in Crystallography
- Drug Transport and Resistance Mechanisms
- Crystallization and Solubility Studies
- Protein Structure and Dynamics
- RNA and protein synthesis mechanisms
- Antibiotic Resistance in Bacteria
- Antibiotics Pharmacokinetics and Efficacy
- Crystallography and molecular interactions
- Analytical Chemistry and Chromatography
- Bacterial Genetics and Biotechnology
- Ion channel regulation and function
- Advanced Proteomics Techniques and Applications
- SARS-CoV-2 and COVID-19 Research
- DNA Repair Mechanisms
- Metabolism and Genetic Disorders
- DNA and Nucleic Acid Chemistry
- Bacteriophages and microbial interactions
- Molecular Sensors and Ion Detection
- Mitochondrial Function and Pathology
- Cardiac electrophysiology and arrhythmias
- Enzyme function and inhibition
- Water Treatment and Disinfection
University of Southampton
2024-2025
King's College London
2017-2025
Trinity House
2017-2024
University of Oxford
2013-2018
Transnational Press London
2018
University of Bristol
2012
SARS-CoV-2 is associated with broad tissue tropism, a characteristic often determined by the availability of entry receptors on host cells. Here, we show that TMEM106B, lysosomal transmembrane protein, can serve as an alternative receptor for into angiotensin-converting enzyme 2 (ACE2)-negative Spike substitution E484D increased TMEM106B binding, thereby enhancing TMEM106B-mediated entry. TMEM106B-specific monoclonal antibodies blocked infection, demonstrating role in viral Using X-ray...
SARS-CoV-2 spike glycoprotein mediates receptor binding and subsequent membrane fusion. It exists in a range of conformations, including closed state unable to bind the ACE2 receptor, an open that does so but displays more exposed antigenic surface. Spikes variants concern (VOCs) acquired amino acid changes linked increased virulence immune evasion. Here, using HDX-MS, we identified dynamics associate with transition from binding, specific mutations VOCs. We show RBD-associated subdomain...
Tripartite resistance nodulation and cell division multidrug efflux pumps span the periplasm are major drivers of among gram-negative bacteria. Cations, such as Mg2+, become concentrated within and, in contrast to cytoplasm, its pH is sensitive conditions outside cell. Here, we reveal an interplay between Mg2+ modulating structural dynamics periplasmic adapter protein, AcrA, function prototypical AcrAB-TolC pump from Escherichia coli. In absence AcrA becomes increasingly plastic acidic...
Multidrug resistance is a serious barrier to successful treatment of many human diseases, including cancer, wherein chemotherapeutics are exported from target cells by membrane-embedded pumps. The most prevalent these pumps, the ATP-Binding Cassette transporter P-glycoprotein (P-gp), consists two homologous halves each comprising one nucleotide-binding domain and six transmembrane helices. region encapsulates hydrophobic cavity, accessed portals in membrane, that binds cytotoxic compounds as...
Abstract The effects of protein–ligand interactions on protein stability are typically monitored by a number established solution-phase assays. Few translate readily to membrane proteins. We have developed an ion-mobility mass spectrometry approach, which discerns ligand binding both soluble and proteins directly via changes in ion mobility, assesses the these through measuring resistance unfolding. Protein unfolding is induced collisional activation, causes structure consequently gas-phase...
Abstract Secondary transporters undergo structural rearrangements to catalyze substrate translocation across the cell membrane – yet how such conformational changes happen within a lipid environment remains poorly understood. Here, we combine hydrogen-deuterium exchange mass spectrometry (HDX-MS) with molecular dynamics (MD) simulations understand lipids regulate of secondary at level. Using homologous XylE, LacY and GlpT from Escherichia coli as model systems, discover that conserved...
Despite the growing importance of mass spectrometry membrane proteins, it is not known how their transfer from solution into vacuum affects stability and structure. To address this we have carried out a systematic investigation ten proteins solubilized in different detergents used to gain physicochemical insight mechanism ionization desolvation. We show that chemical properties mediate charge state, both during detergent removal. Using ion mobility spectrometry, monitor conformations surface...
Abstract The interplay between membrane proteins and the lipids of is important for cellular function, however, tools enabling interrogation protein dynamics within native lipid environments are scarce often invasive. We show that styrene–maleic acid particle (SMALP) technology can be coupled with hydrogen–deuterium exchange mass spectrometry (HDX‐MS) to investigate conformational bilayers. demonstrate changes in accessibility rhomboid protease GlpG, captured three different compositions,...
Photoinitiated polymerization-induced self-assembly (photo-PISA) is an efficient approach to predictably prepare polymeric nanostructures with a wide range of morphologies. Given that this process can be performed at high concentrations and under mild reaction conditions, it has the potential have significant industrial scope. However, given majority (and more specifically biotechnological) formulations contain mixtures polymers surfactants, effect such surfactants on PISA important...
Correctly folded membrane proteins underlie a plethora of cellular processes, but little is known about how they fold. Knowledge folding mechanisms centres on reversible chemically denatured proteins. However, this cannot replicate the unidirectional elongation protein chain during co-translational in cell, where insertion assisted by translocase apparatus. We show that lipid (devoid components) sufficient for successful two bacterial α-helical proteins, DsbB and GlpG. Folding spontaneous,...
Other than more widely used methods, the use of styrene maleic acid copolymers allows direct extraction membrane proteins from lipid bilayer into SMALPs keeping it in its native surrounding.
Ion mobility-mass spectrometry (IM-MS) in combination with molecular modeling offers the potential for small molecule structural isomer identification by measurement of their gas phase collision cross sections (CCSs). Successful application this approach to drug metabolite would facilitate resource reduction, including animal usage, and may benefit other areas pharmaceutical characterization impurity profiling degradation chemistry. However, conformational behavior molecules metabolites is...
Abstract Resistance–nodulation–division efflux pumps play a key role in inherent and evolved multidrug resistance bacteria. AcrB, prototypical member of this protein family, extrudes wide range antimicrobial agents out Although high-resolution structures exist for its conformational fluctuations their putative function are largely unknown. Here, we determine these structural dynamics the presence substrates using hydrogen/deuterium exchange mass spectrometry, complemented by molecular...
Abstract Membrane efflux pumps play a major role in bacterial multidrug resistance. The tripartite pump system from Escherichia coli , AcrAB-TolC, is target for inhibition to lessen resistance development and restore antibiotic efficacy, with homologs other ESKAPE pathogens. Here, we rationalize mechanism of against the periplasmic adaptor protein, AcrA, using combination hydrogen/deuterium exchange mass spectrometry, cellular assays, molecular dynamics simulations. We define structural AcrA...
Strong interactions between lipids and proteins occur primarily through association of charged headgroups amino acid side chains, rendering the protonation status both partners important. Here we use native mass spectrometry to explore lipid binding as a function charge outer membrane porin F (OmpF). We find that anionic phosphatidylglycerol (POPG) or zwitterionic phosphatidylcholine (POPC) OmpF is sensitive electrospray polarity while effects are less pronounced for other in mitochondrial...
Bacteria can resist antibiotics and toxic substances within demanding ecological settings, such as low oxygen, extreme acid, during nutrient starvation. MdtEF, a proton motive force-driven efflux pump from the resistance-nodulation-cell division (RND) superfamily, is upregulated in these conditions but its molecular mechanism unknown. Here, we report cryo-electron microscopy structures of Escherichia coli multidrug transporter MdtF native-lipid nanodiscs, including single-point mutant with...
The HerA-NurA helicase-nuclease complex cooperates with Mre11 and Rad50 to coordinate the repair of double-stranded DNA breaks. Little is known, however, about assembly mechanism activation HerA-NurA. By combining hybrid mass spectrometry cryo-EM, computational biochemical data, we investigate oligomeric formation HerA detail nucleotide binding from thermophilic archaea. We reveal that ATP-free HerA-DNA complexes predominantly exist in solution as a heptamer act loading intermediate. either...
Lipid interactions modulate the function, folding, structure, and organization of membrane proteins. Hydrogen/deuterium exchange mass spectrometry (HDX-MS) has emerged as a useful tool to understand structural dynamics these proteins within lipid environments. Lipids, however, have proven problematic for HDX-MS analysis membrane-embedded due their presence impairing proteolytic digestion, causing liquid chromatography column fouling, ion suppression, and/or spectral overlap. Herein, we...
The mixed donor N-heterocyclic carbene (NHC)/thione ligand precursors [1-(3-R-2H-imidazol-1-yl-2-thione)methyl-3-R-2H-imidazol-2-ium]X, [HCSR]X (R = methyl, benzyl; X Br, I), have been utilized to prepare a range of silver and palladium complexes. coordination CSR silver(I) salts has explored, providing dimeric complexes the type [AgX(CSR)]2 (where R I). Structural characterization [AgX(CSBn)]2 revealed bidentate mode for dinuclear structures where centers are bridged by two bromido centers....
Clinically relevant multidrug-resistant bacteria often arise due to overproduction of membrane-embedded efflux proteins that are capable pumping antibiotics out the bacterial cell before drugs can exert their intended toxic effect. The Escherichia coli membrane protein AcrB is archetypal utilized for study because it extrude a diverse range antibiotic substrates and has close homologues in many Gram-negative pathogens. Three subunits, each which contains 12 transmembrane (TM) helices, known...