Protein-peptidoglycan interactions
Control of peptidoglycan hydrolase activity
Some peptidoglycan hydrolases can cause cell lysis and are therefore potentially lethal enzymes. We are studying the mechanisms that underpin the spatial and temporal control of peptidoglycan hydrolase activity in E. faecalis.
Our work focuses on the enzymes dedicated to septum cleavage during growth and division, more specifically the N-acetylglucosaminidase AtlA. We have recently identified several genes involved in the regulation of septum cleavagein E. faecalis. Their characterisation is in progress.
Our work focuses on the enzymes dedicated to septum cleavage during growth and division, more specifically the N-acetylglucosaminidase AtlA. We have recently identified several genes involved in the regulation of septum cleavagein E. faecalis. Their characterisation is in progress.
Novel tools to study peptidoglycan structure
Peptidoglycan structural analysis is achieved using reversed-phase high pressure liquid chromatography (rp-HPLC) and mass spectrometry (MS).
Most of the work published so far has been carried out using an "offline" strategy; peptidoglycan is purified, digested with a muramidase and reduced before disaccharide-peptides are separated by rp-HPLC. Individual peaks, detected by UV absorbance, are then collected and analysed by mass/tandem mass spectrometry. Spectra are interpreted manually.
In collaboration with Protein Metrics, we are developing a bespoke software for "online" peptidoglycan analysis by LC-MS/MS allowing a high-throughput, automated and unbiased analysis.
Most of the work published so far has been carried out using an "offline" strategy; peptidoglycan is purified, digested with a muramidase and reduced before disaccharide-peptides are separated by rp-HPLC. Individual peaks, detected by UV absorbance, are then collected and analysed by mass/tandem mass spectrometry. Spectra are interpreted manually.
In collaboration with Protein Metrics, we are developing a bespoke software for "online" peptidoglycan analysis by LC-MS/MS allowing a high-throughput, automated and unbiased analysis.
Enterococcal pathogenesis
Enterococci are oportunistic pathogens that can cause a wide range of infections. In collaboration with Simon Foster's lab, we developped a zebrafish model of infection to study host-pathogen interactions.
Our objective is to characterize the contribution the enterococcal cell wall properties to pathogenesis. Most of this work focuses on the analysis of the Enterococcal Polysaccharide Antigen (EPA). We are studying the properties of EPA decorations required for virulence and innate immune evasion.
Our objective is to characterize the contribution the enterococcal cell wall properties to pathogenesis. Most of this work focuses on the analysis of the Enterococcal Polysaccharide Antigen (EPA). We are studying the properties of EPA decorations required for virulence and innate immune evasion.