A5055016134- Bacterial Genetics and Biotechnology
- Vibrio bacteria research studies
- Escherichia coli research studies
- Bacteriophages and microbial interactions
- Antibiotic Resistance in Bacteria
- Bacterial biofilms and quorum sensing
- Lipid Membrane Structure and Behavior
- RNA and protein synthesis mechanisms
- Photosynthetic Processes and Mechanisms
- Monoclonal and Polyclonal Antibodies Research
- Cellular transport and secretion
- Streptococcal Infections and Treatments
- Biocrusts and Microbial Ecology
- Yersinia bacterium, plague, ectoparasites research
- Enzyme Structure and Function
- Algal biology and biofuel production
- Immune Response and Inflammation
- Congenital limb and hand anomalies
- Plant Reproductive Biology
- Botanical Research and Chemistry
- Toxin Mechanisms and Immunotoxins
- Antimicrobial Peptides and Activities
- RNA Interference and Gene Delivery
- Antimicrobial Resistance in Staphylococcus
- Biochemical and Structural Characterization
Dynamique des Génomes et Adaptation Microbienne
2018-2025
Université de Lorraine
2019-2025
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2020-2025
Centre National de la Recherche Scientifique
2012-2023
Aix-Marseille Université
2012-2023
Architecture et Fonction des Macromolécules Biologiques
2009-2023
Laboratoire de Chimie Bactérienne
2018-2023
Institut de Microbiologie de la Méditerranée
2011-2020
Laboratoire d'Ingénierie des Systèmes Macromoléculaires
2011-2018
University of Monastir
2009-2011
The Type VI secretion system (T6SS) is a widespread weapon dedicated to the delivery of toxin proteins into eukaryotic and prokaryotic cells. 13 T6SS subunits assemble cytoplasmic contractile structure anchored cell envelope by membrane-spanning complex. This evolutionarily, structurally functionally related tail bacteriophages. In bacteriophages, assembles onto protein complex, referred as baseplate, that not only serves platform during assembly tube sheath, but also triggers contraction...
Type VI secretion systems (T6SS) are trans-envelope machines dedicated to the of virulence factors into eukaryotic or prokaryotic cells, therefore required for pathogenesis and/or competition towards neighboring bacteria. The T6SS apparatus resembles injection device bacteriophage T4, and is anchored cell envelope through a membrane complex. This complex composed TssL, TssM TagL inner proteins TssJ outer lipoprotein. Here, we report crystal structure enteroaggregative Escherichia coli Sci1...
The Type VI secretion system (T6SS) is a macromolecular machine that mediates bacteria-host or bacteria-bacteria interactions. T6SS core apparatus assembles from 13 proteins form two sub-assemblies: phage-like complex and trans-envelope complex. Hcp, VgrG, TssE, TssB/C subunits are structurally functionally related to components of the tail contractile bacteriophages. This structure thought be anchored membrane by composed TssJ, TssL, TssM proteins. However, how sub-complexes connected...
The type II secretion system enables Gram-negative bacteria to secrete exoproteins into the extracellular milieu. We performed biophysical and biochemical experiments identify systematic interactions between Pseudomonas aeruginosa Xcp components their substrates. observed that three components, XcpPC, secretin XcpQD, pseudopilus tip, directly specifically interact with secreted exoproteins. established in addition its interaction substrate, likely shields entire periplasmic portion of...
Disulfide-rich proteins or DRPs are versatile bioactive compounds that encompass a wide variety of pharmacological, therapeutic, and/or biotechnological applications. Still, the production in sufficient quantities is major bottleneck for their complete structural functional characterization. Recombinant expression such small containing multiple disulfide bonds bacteria E. coli considered difficult and general methods protocols, particularly on high throughput scale, limited. Here we report...
Abstract The stringent response is a general bacterial stress that allows bacteria to adapt and survive adverse conditions. This reprogramming of cell physiology caused by the accumulation alarmone (p)ppGpp which, in Escherichia coli , depends on synthetase RelA bifunctional synthetase/hydrolase SpoT. Although conditions control SpoT-dependent have been described, molecular mechanisms regulating switching from degradation synthesis remain poorly understood. Here, we show protein YtfK...
Gram-negative bacteria use the sophisticated type II secretion system (T2SS) to secrete a large number of exoproteins into extracellular environment. Five proteins T2SS, pseudopilins GspG-H-I-J-K, are proposed assemble pseudopilus involved in extrusion substrate through outer membrane channel. Recent structural data have suggested that three GspI-J-K organized trimeric complex located at tip GspG-containing pseudopilus. In present work we combined two biochemical techniques investigate...
The type VI secretion system (T6SS) is a widespread machine used by bacteria to control their environment and kill or disable bacterial species eukaryotes through toxin injection. T6SS comprises central tube formed of stacked hexamers hemolysin co-regulated proteins (Hcp) terminated trimeric valine-glycine repeat protein G (VgrG) component, the cell puncturing device. A contractile tail sheath, TssB TssC proteins, surrounds this tube. This syringe-like has been compared an inverted phage, as...
Bacterial type IV secretion systems (T4SSs) are widespread nanomachines specialized in the transport across cell envelope of various types molecules including mobile genetic elements during conjugation. Despite their prevalence Gram-positive bacteria, relevant pathogens, assembly and functioning remain unknown. This study addresses these gaps by investigating VirB8 proteins, known to be central components conjugative T4SSs bacteria. However, functional packing precise role biology undefined....
ABSTRACT We present here the functional characterization of a third complete type II secretion system (T2SS) found in newly sequenced Pseudomonas aeruginosa strain PA7. call this Txc (third Xcp homolog). This is encoded by RGP69 region genome plasticity uniquely In addition to 11 txc genes, contains two additional genes encoding possible T2SS substrate and predicted unorthodox sensor protein, TtsS (type sensor). also identified gene two-component response regulator called TtsR regulator),...
Abstract The Type VI secretion system (T6SS) is a versatile machine that delivers toxins into either eukaryotic or bacterial cells. It thus represents key player in pathogenesis and inter-bacterial competition. Schematically, the T6SS can be viewed as contractile tail structure anchored to cell envelope. contraction of sheath propels inner tube loaded with effectors towards target cell. components contracted are then recycled by ClpV AAA + ATPase for new cycle elongation. widespread...
The type VI secretion system (T6SS) is a pathway widespread in Gram-negative bacteria that targets toxins both prokaryotic and eukaryotic cells. Although most T6SSs identified so far are involved inter-bacterial competition, few directly required for full virulence of pathogens. T6SS comprises 13 core proteins assemble large complex structurally functionally similar to phage contractile tail structure anchored the cell envelope by trans-membrane spanning stator. central part this stator,...
Maurocalcine has been the first demonstrated animal toxin acting as a cell-penetrating peptide. Although it possesses competitive advantages, its use peptide (CPP) requires that analogues be developed lack characteristic pharmacological activity on ryanodine-sensitive calcium channels without affecting and vector efficiencies. Here, we present synthesis, three-dimensional 1H NMR structure, of d-maurocalcine. We demonstrate all desired features for an excellent CPP: preserved action,...
The type II secretion system (T2SS) releases large folded exoproteins across the envelope of many Gram-negative pathogens. This process therefore requires specific gating, interacting, and dynamics properties mainly operated by a bipartite outer membrane channel called secretin. We have good understanding structure-function relationship pore-forming C-terminal domain secretins. In contrast, high flexibility their periplasmic N-terminal has been an obstacle in obtaining detailed structural...
The Type VI secretion system (T6SS) is a versatile machine that delivers toxins into either eukaryotic or bacterial cells. At molecular level, the T6SS composed of membrane complex anchors long cytoplasmic tubular structure to cell envelope. This thought resemble tail contractile bacteriophages. It Hcp protein assembles hexameric rings stacked onto each other form tube similar phage tube. proposed be wrapped by called sheath, two proteins, TssB and TssC. has been shown using fluorescence...