A5056376391- Bacteriophages and microbial interactions
- Antibiotic Resistance in Bacteria
- Bacterial biofilms and quorum sensing
- Genomics and Phylogenetic Studies
- Viral gastroenteritis research and epidemiology
- Bacterial Genetics and Biotechnology
- Oral microbiology and periodontitis research
- Escherichia coli research studies
- Plant Virus Research Studies
- Antibiotics Pharmacokinetics and Efficacy
- Evolution and Genetic Dynamics
- Salmonella and Campylobacter epidemiology
- Vibrio bacteria research studies
- Antimicrobial Resistance in Staphylococcus
- Microbial infections and disease research
- Bacterial Identification and Susceptibility Testing
- Microbial Community Ecology and Physiology
- Clostridium difficile and Clostridium perfringens research
- Cystic Fibrosis Research Advances
- Microbial Natural Products and Biosynthesis
- HIV/AIDS oral health manifestations
- Antibiotic Use and Resistance
- Probiotics and Fermented Foods
- Inhalation and Respiratory Drug Delivery
- Plant Pathogenic Bacteria Studies
University of Salford
2013-2024
University of Liverpool
2001-2017
Aix-Marseille Université
2007-2014
Institut de Neurobiologie de la Méditerranée
2007-2009
University of Florida
2006-2007
Microbial ecology provides insights into the ecological and evolutionary dynamics of microbial communities underpinning every ecosystem on Earth. can now be investigated in unprecedented detail, although there is still a wealth open questions to tackled. Here we identify 50 research fundamental importance science or application ecology, with intention summarising field bringing focus new avenues. Questions are categorised seven themes: host-microbiome interactions; health infectious...
Porphyromonas gingivalis can inhibit chemically induced apoptosis in primary cultures of gingival epithelial cells through blocking activation the effector caspase-3. The anti-apoptotic phenotype P. is conserved across strains and does not depend on presence fimbriae, as fimbriae-deficient mutants a naturally occurring non-fimbriated strain were able to impede apoptosis. To dissect survival pathways modulated by gingivalis, protein gene expression number components apoptotic death...
OATP1B1 and OATP1B3 are major hepatic drug transporters whilst OATP1A2 is mainly located in the brain but also liver several other organs. These affect distribution clearance of many endobiotics xenobiotics have been reported to functional single nucleotide polymorphisms (SNPs). We assessed substrate specificities these for a panel antiretrovirals investigated effects SNPs within on pharmacokinetics lopinavir.SLCO1A2, SLCO1B1 SLCO1B3 were cloned, verified used generate cRNA use Xenopuslaevis...
There is growing concern about the relevance of in vitro antimicrobial susceptibility tests when applied to isolates P. aeruginosa from cystic fibrosis (CF) patients. Existing methods rely on single or a few grown aerobically and planktonically. Predetermined cut-offs are used define whether bacteria sensitive resistant any given antibiotic1. However, during chronic lung infections CF, populations exist biofilms there evidence that environment largely microaerophilic2. The stark difference...
Significance During chronic infection, bacterial pathogens undergo rapid evolutionary adaptation and extensive genetic diversification affecting patient symptoms treatment outcomes. Temperate phages are common in pathogen genomes, phage particles can reach high abundance human infections, but their role evolution is unclear. Using experimental population genomics, we show that temperate found infections accelerated by increasing the supply of beneficial mutations imposing strong selection on...
Summary Dental plaque biofilm formation proceeds through a developmental pathway initiated by the attachment of pioneer organisms, such as Streptococcus gordonii, to tooth surfaces. Through variety synergistic interactions, organisms facilitate colonization later arrivals including Porphyromonas gingivalis , potential periodontal pathogen. We have investigated genes S. gordonii required support heterotypic community with P. . By screening plasmid integration library were identified that are...
Background Multi-drug resistant (MDR) infections have become a major concern in hospitals worldwide. This study investigates membrane translocation, which is the first step required for drug action on internal bacterial targets. β-lactams, antibiotic class, use porins to pass through outer barrier of Gram-negative bacteria. Clinical reports linked MDR phenotype altered permeability including porin modification and efflux pump expression. Methodology/Principal Findings Here influx β-lactams...
Pseudomonas aeruginosa is the most common bacterial pathogen infecting lungs of cystic fibrosis (CF) patients. The transmissible Liverpool epidemic strain (LES) harbours multiple inducible prophages (LESϕ2; LESϕ3; LESϕ4; LESϕ5; and LESϕ6), some which are known to confer a competitive advantage in an vivo rat model chronic lung infection. We used quantitative PCR (Q-PCR) measure density dynamics all five LES phages sputa 10 LES-infected CF patients over period 2 years. In patients, densities...
Abstract The Liverpool Epidemic Strain (LES) is a polylysogenic, transmissible strain of Pseudomonas aeruginosa, capable superinfecting existing P. aeruginosa respiratory infections in individuals with cystic fibrosis (CF). LES phages are highly active the CF lung and may have role competitiveness vivo. In this study, we tested by competing isogenic PAO1 strains that differed only presence or absence prophages rat model chronic infection. Lysogens invaded phage-susceptible populations, both...
ABSTRACT A verocytotoxigenic bacteriophage isolated from a strain of enterohemorrhagic Escherichia coli O157, into which kanamycin resistance gene ( aph3 ) had been inserted to inactivate the verocytotoxin vt 2 ), was used infect Enterobacteriaceae strains. number Shigella and E. strains were susceptible lysogenic infection, smooth isolate (O107) also lytic infection. The lysogenized included different serotypes both human animal origin, indicating that this has substantial capacity...
ABSTRACT The periodontal pathogen Porphyromonas gingivalis employs a variety of mechanisms for the uptake hemin and inorganic iron. Previous work demonstrated that in P. may be controlled by LuxS-mediated signaling. In present study, expression genes involved iron was determined parent luxS mutant strains quantitative real-time reverse transcription-PCR. Compared to parental strain, showed reduced levels transcription coding TonB-linked binding protein Tlr lysine-specific protease Kgp, which...
Abstract The rise of next generation sequencing is revealing a hidden diversity temperate phages within the microbial community. While handful these have been well characterized, for vast majority, role phage carriage, and especially multiple poorly understood. Liverpool epidemic strain Pseudomonas aeruginosa an aggressive pathogen in cystic fibrosis lung infections that has recently found to contain several unique prophages its genome. Here, we experimentally investigate two vivo , using...
The pathogenicity of Shiga-like toxin (stx)-producing Escherichia coli (STEC), notably serotype O157, the causative agent hemorrhagic colitis, hemolytic-uremic syndrome, and thrombotic thrombocytopenic purpura, is based partly on presence genes (stx(1) and/or stx(2)) that are known to be carried temperate lambdoid bacteriophages. Stx phages were isolated from different STEC strains found have genome sizes in range 48 62 kb carry either stx(1) or stx(2) genes. Restriction fragment length...
Haloacid dehalogenase (HAD) family phosphatases are widespread in prokaryotes and generally involved metabolic processes. Porphyromonas gingivalis, an invasive periodontal pathogen, secretes the HAD phosphoserine phosphatase SerB653 when contact with gingival epithelial cells. Here we characterize structure enzymatic activity of show that a allelic replacement mutant P. gingivalis is deficient internalization persistence In contrast, mutation second serine (SerB1170), or transporter, did not...
Infection of Escherichia coli by Shiga toxin-encoding bacteriophages (Stx phages) was the pivotal event in evolution deadly E. (STEC), which serotype O157:H7 is most notorious. The number different bacterial species and strains reported to produce toxin now more than 500, since first STEC infection outbreak 1982. Clearly, Stx phages are spreading rapidly, but underlying mechanism for this dissemination has not been explained. Here we show that an essential highly conserved gene product,...
Bacterial adaptation to external stresses and toxic compounds is a key step in the emergence of multidrug-resistant strains that are serious threat human health. Although some proteins regulators involved antibiotic resistance mechanisms have been described, no information available date concerning early bacterial response stresses. Here we report expression ompX, encoding an outer membrane protein, increased during exposure drugs or environmental At same time, level ompF porin noticeably...
Phage production in response to antibiotics varied among four isolates of a Pseudomonas aeruginosa cystic fibrosis (CF) epidemic strain. Whereas ciprofloxacin induced higher levels phage production, other CF-relevant led reduced production. We detected free phages directly CF patient sputum samples by both plaque (40% positive) and PCR (76% assays. Our observations suggest that the choice could influence number within lung environment.
Abstract Background Pseudomonas aeruginosa is the most common bacterial pathogen infecting lungs of patients with cystic fibrosis (CF). The Liverpool Epidemic Strain (LES) transmissible, capable superseding other P. populations and associated increased morbidity. Previously, multiple inducible prophages have been found to coexist in LES chromosome constitute a major component accessory genome not sequenced aerugionosa strains. phages confer competitive advantage rat model chronic lung...
During chronic lung infections of cystic fibrosis patients Pseudomonas aeruginosa populations undergo extensive evolutionary diversification. However, the selective drivers this process are poorly understood. To test effects temperate phages on diversification in P. biofilms we experimentally evolved for approximately 240 generations artificial sputum medium with or without a community three phages.Analysis end-point using suite phenotypic tests revealed within populations, but no...