A5087956705- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Cleft Lip and Palate Research
- Bacteriophages and microbial interactions
- Escherichia coli research studies
- Reconstructive Surgery and Microvascular Techniques
- Genomics and Phylogenetic Studies
- Protein Structure and Dynamics
- Tracheal and airway disorders
- Bacterial biofilms and quorum sensing
- Antibiotic Resistance in Bacteria
- DNA Repair Mechanisms
- Antimicrobial Resistance in Staphylococcus
- Biochemical and Structural Characterization
- RNA Interference and Gene Delivery
- Oral and Maxillofacial Pathology
- Vascular Malformations and Hemangiomas
- Lipid Membrane Structure and Behavior
- Antimicrobial Peptides and Activities
- Photosynthetic Processes and Mechanisms
- Bone Tumor Diagnosis and Treatments
- Craniofacial Disorders and Treatments
- Clinical Nutrition and Gastroenterology
- Plant Pathogenic Bacteria Studies
- Female Genital Mutilation/Cutting Issues
University of Nottingham
2009-2024
University of Liverpool
2015-2020
Alder Hey Children's Hospital
2015-2020
Queen's Medical Centre
2003-2014
Alder Hey Children's NHS Foundation Trust
2010
Institute of Infection and Immunity
2005-2009
In-Q-Tel
2009
Glan Clwyd Hospital
1996-2007
University of East Anglia
1994-2005
University of York
2005
The phytotoxin coronatine and the plant growth regulator methyl jasmonate (MeJA) caused similar growth-inhibitory effects on Arabidopsis seedlings. To test whether these two compounds have action, 14 independent coi1 (coronatine-insensitive) mutants of were selected. segregated as single recessive Mendelian markers, all alleles at locus. All also insensitive to MeJA male sterile. Both inhibited root growth, stimulated anthocyanin accumulation, increased level proteins ~31 ~29 kD detected in...
Pseudomonas aeruginosa is an opportunistic pathogen and the leading cause of morbidity mortality in cystic fibrosis (CF) patients. P. infections are difficult to treat due a number antibiotic resistance mechanisms organism's propensity form multicellular biofilms. Epidemic strains often dominate within lungs individual CF patients, but how they achieve this poorly understood. One way that can compete by producing chromosomally encoded bacteriocins, called pyocins. Three major classes pyocin...
Nuclease colicins bind their target receptor in the outer membrane of sensitive cells form a high affinity complex with cognate immunity proteins. Upon cell entry protein is lost from by means that are poorly understood. We have developed fluorescence assay has enabled us to study molecular requirements for release. use members tol operon translocation across membrane. demonstrated amino-terminal 80 residues colicin E9 molecule, which region interacts TolB, essential Using deletion strains...
Summary: E colicins are plasmid-coded, protein antibiotics which bind to the BtuB outer membrane receptor of Escherichia coli cells and then translocated either surface cytoplasmic in case pore-forming colicin E1, or cytoplasm enzymic E2-E9. Translocation has been proposed be dependent on a putative TolA box; pentapeptide (DGSGW) located N-terminal 39 residues several Toldependent colicins. In this study, site-directed mutagenesis was used change each box E9 alanines. two glycine residues,...
We have developed a polypeptide lysostaphin FRET (fluorescence resonance energy transfer) substrate (MV11F) for the endopeptidase activity of lysostaphin. Site-directed mutants that abolished killing against Staphylococcus aureus also completely inhibited MV11 substrate. Lysostaphin-producing staphylococci are resistant to by through incorporation serine residues at positions 3 and 5 pentaglycine cross-bridge in their cell walls. The was engineered introduce residue each four target site it...
Interaction of the TolB box Group A colicins with protein in periplasm Escherichia coli cells promotes transport cytotoxic domain colicin across cell envelope. The crystal structure a complex between 107-residue peptide (TA(1-107)) translocation (ColA) and identified as 12-residue that folded into distorted hairpin within central canyon beta-propeller TolB. Comparison this E9 (ColE9) box-TolB complex, together site-directed mutagenesis ColA residues, revealed important differences...
The mechanism by which E colicins recognize and then bind to BtuB receptors in the outer membrane of Escherichia coli cells is a poorly understood first step process that results cell killing. Using N‐ C‐terminal deletions N‐terminal 448 residues colicin E9, we demonstrated smallest polypeptide encoded one these constructs retained receptor‐binding activity consisted 343–418. vivo assay were supported an alternative competition developed using fusion protein consisting 1–497 E9 fused green...
The events that occur after the binding of enzymatic E colicins to Escherichia coli BtuB receptors lead translocation cytotoxic domain into periplasmic space and, ultimately, cell killing are poorly understood. It has been suggested unfolding coiled-coil receptor may be an essential step leads loss immunity protein from colicin and complex then triggers translocation. We introduced pairs cysteine mutations E9 (ColE9) resulted in formation a disulfide bond located near middle or top R domain....
Lysostaphin (EC. 3.4.24.75) is a protein secreted by Staphylococcus simulans biovar staphylolyticus and has been shown to be active against methicillin resistant S. aureus (MRSA). The design synthesis of three internally quenched substrates for lysostaphin based on the peptidoglycan crossbridges aureus, their use in fluorescence resonance energy transfer (FRET) assays reported. These enabled gathering information about endopeptidase activity effect that mutations have its enzymatic ability....
ABSTRACT ColE9 is a plasmid-encoded protein antibiotic produced by Escherichia coli and closely related species that kills E. cells expressing the BtuB receptor. The 15-kDa cytotoxic DNase domain of colicin E9 preferentially nicks double-stranded DNA at thymine bases shares common active-site structural motif with variety other nucleases, including H-N-H homing endonucleases apoptotic CAD proteins eukaryotes. Studies mechanism which reaches cytoplasm are limited lack rapid, sensitive assay...
The mechanism by which enzymatic E colicins such as colicin E3 (ColE3) and ColE9 cross the outer membrane, periplasm, cytoplasmic membrane to reach cytoplasm thus kill Escherichia coli cells is unique in prokaryotic biology but poorly understood. This requires an interaction between TolB periplasm three essential residues, D35, S37, W39, of a pentapeptide sequence called box located N-terminal translocation domain colicins. Here we used site-directed mutagenesis demonstrate that actually...
The Tol assembly of proteins is an interacting network located in the Escherichia coli cell envelope that transduces energy and contributes to integrity. TolA central this linking inner outer membranes by interactions with TolQ, TolR, TolB, Pal. Group A colicins, such as ColA, parasitize through and/or TolB facilitate translocation reach their cytotoxic site action. We have determined first structure C-terminal domain (TolAIII) bound N-terminal ColA polypeptide (TA(53-107)). interface region...