A5019165242- Bacterial Genetics and Biotechnology
- Bacteriophages and microbial interactions
- RNA and protein synthesis mechanisms
- Antibiotic Resistance in Bacteria
- Legume Nitrogen Fixing Symbiosis
- DNA Repair Mechanisms
- Genomics and Phylogenetic Studies
- Escherichia coli research studies
- Plant Pathogenic Bacteria Studies
- Iron Metabolism and Disorders
- Advanced biosensing and bioanalysis techniques
- Microbial Community Ecology and Physiology
- Enzyme Structure and Function
- DNA and Nucleic Acid Chemistry
- Trace Elements in Health
- Nanopore and Nanochannel Transport Studies
- Evolution and Genetic Dynamics
- RNA Interference and Gene Delivery
- Protist diversity and phylogeny
- RNA Research and Splicing
- Drug Transport and Resistance Mechanisms
- RNA modifications and cancer
- Microplastics and Plastic Pollution
- Metalloenzymes and iron-sulfur proteins
- Chemical Reactions and Isotopes
Université Toulouse III - Paul Sabatier
2016-2025
Centre National de la Recherche Scientifique
2014-2025
Laboratoire de Microbiologie et Génétique Moléculaires
2015-2024
Université de Toulouse
2015-2024
Laboratoire de Mécanique et Génie Civil
2021
Boonton Public Schools
2009
University of Toronto
1999-2000
Precise and rapid DNA segregation is required for proper inheritance of genetic material. In most bacteria archaea, this process assured by a broadly conserved mitotic-like apparatus in which NTPase (ParA) displaces the partition complex. Competing observations models imply starkly different 3D localization patterns components machinery during segregation. Here we use super-resolution microscopies to localize each component with respect bacterial chromosome. We show that Par proteins locate...
ABSTRACT P1 bacteriophages lysogenize bacteria as independent plasmid-like elements. We describe here a P1-like bacteriophage, RCS47, carrying bla SHV-2 gene, isolated from clinical strain of Escherichia coli phylogroup B1, and we report the prevalence prophages in natural E. isolates. found that 70% sequence 115-kb circular molecule, was common to reference bacteriophage under GenBank accession no. AF234172.1 , with shared sequences being 99% identical. RCS47 had acquired two main foreign...
Article16 November 2018Open Access Transparent process A conserved mechanism drives partition complex assembly on bacterial chromosomes and plasmids Roxanne E Debaugny Laboratoire de Microbiologie et Génétique Moléculaires, Centre Biologie Intégrative (CBI), National la Recherche Scientifique (CNRS), Université Toulouse, UPS, France Search for more papers by this author Aurore Sanchez Jérôme Rech Delphine Labourdette LISBP, CNRS, INRA, INSA, Dorignac Charles Coulomb, CNRS-Université...
In bacteria, mitotic stability of plasmids and many chromosomes depends on replicon-specific systems which comprise a centromere, centromere-binding protein an ATPase. Dynamic self-assembly the ATPase appears to enable active partition replicon copies into cell-halves, but for most ATPases (the Walker-box type) mechanism is unknown. Also unknown how host cell contributes partition. We have examined effects non-sequence-specific DNA in vitro SopA plasmid F. underwent polymerization provided...
Bacterial ATPases belonging to the ParA family assure partition of their replicons by forming dynamic assemblies which move replicon copies into new cell-halves. The mechanism underlying is not understood for Walker-box ATPase class, includes most plasmid and all chromosomal ParAs. studied both polymerize interact with non-specific DNA in an ATP-dependent manner. Previous work showed that vitro, polymerization one such ATPase, SopA F, inhibited DNA, suggesting interaction host nucleoid could...
In bacteria, mitotic stability of plasmids and many chromosomes depends on replicon-specific systems, which comprise a centromere, centromere-binding protein an ATPase. Dynamic self-assembly the ATPase appears to enable active partition replicon copies into cell-halves, but for Walker-box ATPases molecular mechanism is unknown. activity be essential this process. DNA proteins are known stimulate details stimulation have not been reported. We investigated interactions ATP hydrolysis by SopA...
Abstract The human pathogen Mycobacterium tuberculosis requires a P 1B -ATPase metal exporter, CtpC (Rv3270), for resistance to zinc poisoning. Here, we show that also depends on chaperone-like protein, PacL1 (Rv3269). contains transmembrane domain, cytoplasmic region with glutamine/alanine repeats and C-terminal metal-binding motif (MBM). binds Zn 2+ , but the MBM is required only at high concentrations. co-localizes in dynamic foci mycobacterial plasma membrane, two proteins form molecular...
Cell function relies on liquid-like organelles formed through phase transitions, yet the mechanisms ensuring their specificity and rapid assembly remain poorly understood. In bacterial chromosome segregation via ParABS system, hundreds of ParB proteins are recruited around centromere-like parS sequence forming partition complex. Recent studies have shown that binds CTP undergoes cycles binding unbinding near parS, however, this accounts for recruitment only a small fraction molecules,...
Metal ion homeostasis is crucial for bacterial pathogens to withstand metal-induced stress during infection. However, the mechanisms underlying resistance metal remain incompletely understood, particularly how bacteria coordinate responses simultaneous exposure multiple metals. Here, we uncover a previously unrecognized mechanism by which Mycobacterium tuberculosis, causative agent of orchestrates coordinated response multi-metal stress. We demonstrate that M. tuberculosis assembles dynamic,...
Hydrolysis of ATP by partition ATPases, although considered a key step in the segregation mechanism that assures stable inheritance plasmids, is intrinsically very weak. The cognate centromere-binding protein (CBP), together with DNA, stimulates ATPase to hydrolyse and undertake relocation incites plasmid movement, apparently confirming need for hydrolysis partition. However, ATP-binding alone changes conformation properties, making it difficult rigorously distinguish substrate cofactor...
Efficient bacterial chromosome segregation typically requires the coordinated action of a three-component machinery, fueled by adenosine triphosphate, called partition complex. We present phenomenological model accounting for dynamic activity this system that is also relevant physics catalytic particles in active environments. The obtained coupling simple linear reaction-diffusion equations with proteophoresis, or "volumetric" chemophoresis, force field arises from protein-protein...
Bacterial ParB partitioning proteins involved in chromosomes and low-copy-number plasmid segregation are cytosine triphosphate (CTP)-dependent molecular switches. CTP-binding converts dimers to DNA clamps, allowing unidimensional diffusion along the DNA. This sliding property has been proposed explain spreading over large distances from parS centromere sites where is specifically loaded. We modeled such a "clamping sliding" mechanism as typical reaction-diffusion system, compared it F...
The SopA protein plays an essential, though so far undefined, role in partition of the mini-F plasmid but, when overproduced, it causes loss from growing cells. Our investigation this phenomenon has revealed that excess reduces linking number mini-F. It appears to do by disturbing complex, which SopB normally introduces local positive supercoiling upon binding sopC centromere, as occurs only plasmids carrying and presence protein. SopA-induced reduction is not associated with altered sop...
Summary Low‐copy number plasmids of bacteria rely on specific centromeres for regular partition into daughter cells. When also present a second plasmid, the centromere can render two incompatible, disrupting and causing plasmid loss. We have investigated basis incompatibility exerted by F centromere, sopC , to probe mechanism partition. Measurements effects at various gene dosages destabilization mini‐F, repression sopAB operon occupancy mini‐F DNA centromere‐binding protein, SopB, revealed...
ParB proteins are one of the three essential components partition systems that actively segregate bacterial chromosomes and plasmids. In binding to centromere sequences, assembles as nucleoprotein structures called complexes. These assemblies substrates for partitioning process ensures DNA molecules segregated both sides cell. We recently identified sopC nucleotides required homologue plasmid F, SopB. This analysis also suggested a role in an arginine residue, R219, located outside...
The P1 plasmid prophage is faithfully partitioned by a high affinity nucleoprotein complex assembled at the centromere-like parS site. This partition composed of ParB and Escherichia coli integration host factor (IHF), bound specifically to parS. We have investigated assembly its stoichiometry binding. Measured gel mobility shift assays, IHF bind tightly form specific complex, called I + B1. observed that as concentration was increased, second, larger (I B2) formed, followed formation...