A5041601046- Antibiotic Resistance in Bacteria
- Essential Oils and Antimicrobial Activity
- Bacterial biofilms and quorum sensing
- Antibiotics Pharmacokinetics and Efficacy
- Bacterial Genetics and Biotechnology
- Phytochemistry Medicinal Plant Applications
- Vibrio bacteria research studies
- Microbial Metabolism and Applications
- Complementary and Alternative Medicine Studies
- Antibiotic Use and Resistance
- Enzyme Production and Characterization
- Antimicrobial agents and applications
- Infections and bacterial resistance
- Inhalation and Respiratory Drug Delivery
- Advanced Chemical Sensor Technologies
- Antimicrobial Resistance in Staphylococcus
- Cystic Fibrosis Research Advances
- Salmonella and Campylobacter epidemiology
- Analytical Chemistry and Chromatography
- Bee Products Chemical Analysis
- Phenothiazines and Benzothiazines Synthesis and Activities
- bioluminescence and chemiluminescence research
- Pharmaceutical and Antibiotic Environmental Impacts
- Pharmaceutical studies and practices
- Bacterial Infections and Vaccines
Université Bourgogne Franche-Comté
2017-2024
Laboratoire Chrono-Environnement
2015-2023
Centre National de la Recherche Scientifique
1990-2022
Université Marie et Louis Pasteur
2020-2022
University of Liverpool
2020
Université de Bourgogne
2017-2020
Sapienza University of Rome
2020
Université de franche-comté
1989-2016
CNR de la Résistance aux Antibiotiques
2013
Centre Hospitalier Universitaire de Besançon
2009
Bacterial resistance to β-lactams may rely on acquired β-lactamases encoded by class 1 integron-borne genes. Rearrangement of integron cassette arrays is mediated the integrase IntI1. It has been previously established that expression can be activated SOS response in vitro, leading speculation this an important clinical mechanism acquiring resistance. Here we report first vivo evidence impact antibiotic treatment given a patient and its output terms development. We identified new modulation...
To investigate the resistance mechanisms of β-lactam-resistant Pseudomonas aeruginosa isolated from cystic fibrosis (CF) patients in France. Two-hundred-and-four P. CF isolates were collected 10 French university hospitals 2007. Their susceptibility to 14 antibiotics and their β-lactams investigated. β-lactamase contents characterized by isoelectric focusing, PCR enzymatic assays. Expression levels efflux pumps intrinsic AmpC quantified reverse transcription real-time quantitative PCR....
ABSTRACT Multidrug-resistant mutants of Pseudomonas aeruginosa that overproduce the active efflux system MexEF-OprN (called nfxC mutants) have rarely been characterized in hospital setting. Screening 221 clinical strains exhibiting a reduced susceptibility to ciprofloxacin (a substrate MexEF-OprN) and imipenem negatively coregulated porin OprD) led identification 43 (19.5%) mutants. Subsequent analysis 22 nonredundant showed that, contrast their vitro -selected counterparts, only 3 them...
Essential oils or their components are increasingly used to fight bacterial infections. Cinnamaldehyde (CNA), the main constituent of cinnamon bark oil, has demonstrated interesting properties in vitro against various pathogens, including Pseudomonas aeruginosa . In present study, we investigated mechanisms and possible therapeutic consequences P. adaptation CNA.
ABSTRACT The multidrug efflux system MexEF-OprN is produced at low levels in wild-type strains of Pseudomonas aeruginosa . However, so-called nfxC mutants, mutational alteration the gene mexS results constitutive overexpression pump, along with increased resistance bacterium to chloramphenicol, fluoroquinolones, and trimethoprim. In this study, analysis vitro -selected chloramphenicol-resistant clones strain PA14 led identification a new class MexEF-OprN-overproducing mutants (called nfxC2 )...
ABSTRACT When overproduced, the multidrug efflux system MexEF-OprN increases resistance of Pseudomonas aeruginosa to fluoroquinolones, chloramphenicol, and trimethoprim. In this work, we demonstrate that gain-of-function mutations in regulatory gene mexT result oligomerization LysR regulator MexT, constitutive upregulation pump, increased clinical isolates.
ABSTRACT A survey conducted between 1987 and 1994 at the University Hospital of Besançon, France, demonstrated a dramatic increase (from 0 to 42.5%) in prevalence amoxicillin resistance among Salmonella spp. Of 96 resistant isolates collected during this period (including 77 Typhimurium), 54 were found produce TEM-1 β-lactamase, 40 produced PSE-1 (equivalent CARB-2), one plus TEM-2, OXA-1 isoelectric focusing DNA hybridization experiments. Plasmids coding for these β-lactamases further...
Abstract To overcome the metal restriction imposed by host’s nutritional immunity, pathogenic bacteria use high affinity molecules called metallophores. Metallophore‐mediated uptake pathways necessitate complex cycles of synthesis, secretion, and recovery metallophore across bacterial envelope. We recently discovered staphylopine pseudopaline, two members a new family broad‐spectrum metallophores important for survival during infections. Here, we are expending molecular understanding...
AxyXY-OprZ is an RND-type efflux system that confers innate aminoglycoside resistance to Achromobacter spp. We investigated here a putative TetR family transcriptional regulator encoded by the axyZ gene located upstream of axyXY-oprZ An in-frame deletion assay led increased MICs antibiotic substrates system, including aminoglycosides, cefepime, fluoroquinolones, tetracyclines, and erythromycin, indicating product negatively regulates expression Moreover, we identified amino acid substitution...
Abstract Acetylcholinesterase (AChE; EC 3.1.1.7) is expressed in the central nervous system multiple molecular forms that may subserve functions and be selectively lost neurodegenerative illnesses such as Alzheimer's disease. AChE expression has been studied primary cultures of developing vertebrate system, but investigation limited by lack a suitable human CNS surrogate cell model for vitro studies inability brain to provide large numbers pure neurons. To develop an neuronal function, we...
ABSTRACT Exposure of Pseudomonas aeruginosa to cinnamaldehyde (CNA), a natural electrophilic antimicrobial often used as self-medication treat mild infections, triggers overproduction the MexAB-OprM efflux system, leading multidrug resistance. In this study, we demonstrate that CNA exposure induces expression genes regulated by two-component system AmgRS. AmgRS activates production, independent repressors MexR and NalD. addition essential role played NalC-ArmR pathway in adaptive process, is...
Cinnamaldehyde (CNA), the main component of cinnamon essential oil, is one most active plant compounds against nosocomial pathogen Pseudomonas aeruginosa. Exposure wild-type strain PA14 (MIC 700 µg/mL) for 5 to 10 days fixed (900 or increasing (from 900 1400 concentrations this natural antibacterial resulted in emergence resistant mutants CNA-A1 A3, and CNA-B1 B7, respectively. Genome sequencing experiments showed that each A3 differed from by SNP, a slight increase CNA resistance level...
Essential oils (EOs) or their components are widely used by inhalation nebulization to fight mild respiratory bacterial infections. However, interaction with antibiotics is poorly known. In this study we evaluated the effects of citral, main component lemongrass oil, on in vitro susceptibility Pseudomonas aeruginosa antibiotics. Exposure strain PA14 subinhibitory concentrations citral increased expression operons encoding multidrug efflux systems MexEF-OprN and MexXY/OprM, resistance...
ABSTRACT The ability for all organisms to acquire metals from their environment is essential life. To overcome the metal restriction imposed by host’s nutritional immunity, bacterial pathogens exploits use of small high affinity molecules called metallophores. Metallophores are first synthetized in cytoplasm, then secreted into medium where they sequester metal. metal-metallophore complex imported bacterium following binding dedicated cell surface receptors. Recently, a new family...