A5050982418- Bacterial Genetics and Biotechnology
- Bacterial biofilms and quorum sensing
- RNA and protein synthesis mechanisms
- Bacteriophages and microbial interactions
- Protist diversity and phylogeny
- Genomics and Phylogenetic Studies
- Microbial Community Ecology and Physiology
- Plant and Biological Electrophysiology Studies
- Escherichia coli research studies
- Cellular transport and secretion
- Biotin and Related Studies
- Antimicrobial Peptides and Activities
- Transgenic Plants and Applications
- Cell Image Analysis Techniques
- Advanced Fluorescence Microscopy Techniques
- Biochemical and Structural Characterization
- Microbial Fuel Cells and Bioremediation
- Photosynthetic Processes and Mechanisms
- CRISPR and Genetic Engineering
- Bacillus and Francisella bacterial research
- Vibrio bacteria research studies
- Bacterial Infections and Vaccines
- Photoreceptor and optogenetics research
Laboratoire de Chimie Bactérienne
2013-2025
Centre National de la Recherche Scientifique
2013-2024
Institut de Microbiologie de la Méditerranée
2013-2022
Aix-Marseille Université
2013-2022
University of California, Berkeley
2007-2010
Federico II University Hospital
2007
University of Naples Federico II
2003-2006
Myxococcus xanthus moves by gliding motility powered Type IV pili (S-motility) and a second system, A-motility, whose mechanism remains elusive despite the identification of ∼40 A-motility genes. In this study, we used biochemistry cell biology analyses to identify multi-protein complexes associated with A-motility. Previously, showed that N-terminal domain FrzCD, receptor for frizzy chemosensory pathway, interacts two proteins, AglZ AgmU. Here characterized AgmU, protein localized both...
The development of multicellularity is a key evolutionary transition allowing for differentiation physiological functions across cell population that confers survival benefits; among unicellular bacteria, this can lead to complex developmental behaviors and the formation higher-order community structures. Herein, we demonstrate in social δ-proteobacterium Myxococcus xanthus, secretion novel biosurfactant polysaccharide (BPS) spatially modulated within communities, mediating swarm migration...
Significance The type IV pilus (Tfp) is a multipurpose machine found on bacterial surfaces that works by cycles of synthesis/retraction pilin fiber. During surface (twitching) motility, the coordinated actions multiple Tfps at cell pole promotes single cells and synchronized group movements. Here, directly observing polar Tfp machines in action during motility Myxococcus xanthus , we identified mechanism underlying pole-specific activation. In this process, Ras-like protein MglA targets...
Directional motility in the gliding bacterium Myxococcus xanthus requires controlled cell reversals mediated by Frz chemosensory system. FrzCD, a cytoplasmic chemoreceptor, does not form membrane-bound polar clusters typical for most bacteria, but rather that appear helically arranged and span length. The distribution of FrzCD living cells was found to be dynamic: localized continuously changed their size, number, position. number correlated with cellular reversal frequency: fewer were...
Eukaryotic cells utilize an arsenal of processive transport systems to deliver macromolecules specific subcellular sites. In prokaryotes, such mechanisms have only been shown mediate gliding motility, a form microbial surface translocation. Here, we show that the motility function Myxococcus xanthus Agl-Glt machinery results from recent specialization versatile class bacterial transporters. Specifically, demonstrate Agl motor is modular and dissociates rest (the Glt complex) bind newly...
Understanding the principles underlying plasticity of signal transduction networks is fundamental to decipher functioning living cells. In Myxococcus xanthus, a particular chemosensory system (Frz) coordinates activity two separate motility systems (the A- and S-motility systems), promoting multicellular development. This unusual structure asks how transduced in branched pathway. Using combined evolution-guided single cell approaches, we successfully uncoupled regulations showed that...
Myxococcus xanthus moves by gliding motility powered type IV pili (S-motility) and distributed motor complexes (A-motility). The Frz chemosensory pathway controls reversals for both systems. However, it is unclear how the can communicate with these different In this article, we show that FrzCD, receptor, interacts AglZ, a protein associated A-motility. Affinity chromatography cross-linking experiments showed FrzCD-AglZ interaction occurs between uncharacterized N-terminal region of FrzCD...
Chemosensory systems (CSS) are complex regulatory pathways capable of perceiving external signals and translating them into different cellular behaviors such as motility development. In the δ-proteobacterium Myxococcus xanthus, chemosensing allows groups cells to orient themselves aggregate specialized multicellular biofilms termed fruiting bodies. M. xanthus contains eight predicted CSS 21 chemoreceptors. this work, we systematically deleted genes encoding components each chemoreceptors...
ABSTRACT In bacterial chemosensing, environmental cues are typically sensed by transmembrane receptors known as methyl-accepting chemotaxis proteins (MCPs). MCPs form highly organized arrays using the membrane a scaffold. These amplify signals and transduce them into cellular response. The FrzCD cytoplasmic receptor from Myxococcus xanthus is unique due to its ability bind DNA use nucleoid scaffold arrays. this study, we identified two HAMP ( h istidine kinase, denylyl cyclase, M CP, p...
BioTechniquesVol. 42, No. 2 BenchmarksOpen AccessAmino terminal fusion of heterologous proteins to CotC increases display efficiencies in the Bacillus subtilis spore systemRachele Isticato, Donatella Scotto Di Mase, Emilia M.F. Mauriello, Maurilio De Felice & Ezio RiccaRachele IsticatoUniversity Federico II, Naples, Italy, MaseUniversity MaurielloUniversity FeliceUniversity Italy Ricca*Address correspondence Udaykumar Ranga, Molecular Virology Laboratory, Biology and Genetics Unit,...
Abstract In rod‐shaped bacteria, type IV pili (Tfp) promote twitching motility by assembling and retracting at the cell pole. Myxococcus xanthus , a bacterium that moves in highly coordinated groups, Tfp are activated polar activator protein, SgmX. However, while it is known Ras‐like protein MglA required for unipolar targeting, how SgmX accesses pole to activate unknown. Here, we demonstrate beacon FrzS, recruits We identified two main functional domains, including Tfp‐activating domain...
Type Four Pili (T4P) are extracellular appendages mediating several bacterial functions such as motility, biofilm formation and infection. The ability to adhere substrates is essential for all these functions. In Myxococcus xanthus , during twitching the binding of polar T4P exopolysaccharides (EPS), induces pilus retraction forward cell movement. EPS produced, secreted weakly associated M . surface or deposited on substrate. this study, a genetic screen allowed us identify two factors...
The FrzCD chemoreceptor from the gliding bacterium Myxococcus xanthus forms cytoplasmic clusters that occupy a large central region of cell body also occupied by nucleoid. In this work, we show directly binds to nucleoid with its N-terminal positively charged tail and recruits active signaling complexes at location. binding occur in DNA-sequence independent manner leads formation multiple distributed explore constrained areas. This organization might be required for cooperative interactions...
Summary Myxococcus xanthus requires gliding motility for swarming and fruiting body formation. It uses the Frz chemosensory pathway to regulate cell reversals. FrzCD is a cytoplasmic chemoreceptor required sensing effectors this pathway. NarX transmembrane sensor nitrate from Escherichia coli . In study, two NarX–FrzCD chimeras were constructed investigate M. chemotaxis: NazD F contains N‐terminal sensory module of fused C‐terminal signalling domain FrzCD; R similar except that it G51R...
ABSTRACT Citrobacter rodentium is a murine pathogen that now widely used as an in vivo model for gastrointestinal infections due to its similarities with human enteropathogens, such the possession of locus enterocyte effacement (the LEE island). We studied lrp gene C. and found it encodes product highly similar members Lrp (leucine-responsive regulatory protein) family transcriptional regulators, able recognize leucine effector repress expression own structural gene. In enterobacteria,...
The structures responsible for photosynthesis in bacteria use the nucleoid and two unique proteins as a scaffold to position themselves.
Chemosensory systems are highly organized signaling pathways that allow bacteria to adapt environmental changes. The Frz chemosensory system from M. xanthus possesses two CheW-like proteins, FrzA (the core CheW) and FrzB. We found FrzB does not interact with FrzE cognate CheA) as it lacks the amino acid region responsible for this interaction. FrzB, instead, acts upstream of FrzCD in regulation chemotaxis behaviors activates pathway by allowing formation distribution multiple clusters on...