Xavier Nassif

Type IV pilus retraction in pathogenic Neisseria is regulated by the PilC proteins (2004)

Morand,Philippe C., Bille,Emmanuelle, Morelle,Sandrine, Eugene,Emmanuel, Beretti,Jean-Luc, Wolfgang,Matthew, ...

Pathogenic Neisseria express type IV pili (tfp), which have been shown to play a central role in the interactions of bacteria with their environment. The regulation of piliation thus constitutes a...

The meningococcal PilT protein is required for induction of intimate attachment to epithelial cells following pilus-mediated adhesion

Pujol, Céline, Eugène, Emmanuel, Marceau, Michaël, Nassif, Xavier

The ability of Neisseria meningitidis (MC) to interact with cellular barriers is essential to its pathogenesis. With epithelial cells, this process has been modeled in two steps. The initial stage of...

Role of Glycosylation at Ser63 in Production of Soluble Pilin in Pathogenic Neisseria

Marceau, Michael, Nassif, Xavier

Pilus-mediated adhesion is essential in the pathogenesis of Neisseria meningitidis (MC) and Neisseria gonorrhoeae (GC). Pili are assembled from a protein subunit called pilin. Pilin is a...

Identification of Regions of the Chromosome of Neisseria meningitidis and Neisseria gonorrhoeae Which Are Specific to the Pathogenic Neisseria Species

Perrin, Agnes, Nassif, Xavier, Tinsley, Colin

Neisseria meningitidis and Neisseria gonorrhoeae give rise to dramatically different diseases. Their interactions with the host, however, do share common characteristics: they are both human...

Molecular and Biological Analysis of Eight Genetic Islands That Distinguish Neisseria meningitidis from the Closely Related Pathogen Neisseria gonorrhoeae

Klee, Silke R., Nassif, Xavier, Kusecek, Barica, Merker, Petra, Beretti, Jean-Luc, Achtman, Mark, ...

The pathogenic species Neisseria meningitidis and Neisseria gonorrhoeae cause dramatically different diseases despite strong relatedness at the genetic and biochemical levels. N. meningitidis can...

Identification of Regions of the Escherichia coli Chromosome Specific for Neonatal Meningitis-Associated Strains

Bonacorsi, Stéphane Pierre Paul, Clermont, Olivier, Tinsley, Colin, Le Gall, Isabelle, Beaudoin, Jean-Christophe, Elion, Jacques, ...

Specific virulence factors associated with the pathogenesis of Escherichia coli strains causing neonatal meningitis (ECNM), such as the K1 capsular polysaccharide, the S fimbriae, and the Ibe10...

Mutagenesis of Neisseria meningitidis by In Vitro Transposition of Himar1 mariner

Pelicic, Vladimir, Morelle, Sandrine, Lampe, David, Nassif, Xavier

Now that the meningococcal genome sequence has been completed, the lack of a suitable method for saturation mutagenesis remains a major obstacle to the unraveling of the pathogenic propensity of...

A Uropathogenicity Island Contributes to the Pathogenicity of Escherichia coli Strains That Cause Neonatal Meningitis

Houdouin, Véronique, Bonacorsi, Stéphane, Brahimi, Naima, Clermont, Olivier, Nassif, Xavier, Bingen, Edouard

We report that the archetypal Escherichia coli strain C5 causing neonatal meningitis harbors a pathogenicity island (PAI) designated PAI IC5 that is similar to the PAI IIJ96 of uropathogenic E. coli...

Representational Difference Analysis between Afa/Dr Diffusely Adhering Escherichia coli and Nonpathogenic E. coli K-12

Blanc-Potard, Anne-Beatrice, Tinsley, Colin, Scaletsky, Isabel, Le Bouguenec, Chantal, Guignot, Julie, Servin, Alain L., ...

Diffusely adhering Escherichia coli strains harboring Afa/Dr adhesins (Afa/Dr DAEC) have been associated with diarrhea and urinary tract infections (UTIs). The present work is the first extensive...

Comparative Genomics Identifies the Genetic Islands That Distinguish Neisseria meningitidis, the Agent of Cerebrospinal Meningitis, from Other Neisseria Species

Perrin, Agnès, Bonacorsi, Stéphane, Carbonnelle, Etienne, Talibi, Driss, Dessen, Philippe, Nassif, Xavier, ...

Neisseria meningitidis colonizes the nasopharynx and, unlike commensal Neisseria species, is capable of entering the bloodstream, crossing the blood-brain barrier, and invading the meninges. The...

Neisseria meningitidis RTX Proteins Are Not Required for Virulence in Infant Rats

Forman, Stanislav, Linhartova, Irena, Osicka, Radim, Nassif, Xavier, Sebo, Peter, Pelicic, Vladimir

RTX cytotoxins play an important role in virulence of numerous gram-negative pathogens. Unexpectedly, however, we show here that the RTX proteins of Neisseria meningitidis are dispensable for...

The REP2 Repeats of the Genome of Neisseria meningitidis Are Associated with Genes Coordinately Regulated during Bacterial Cell Interaction

Morelle, Sandrine, Carbonnelle, Etienne, Nassif, Xavier

Interaction with host cells is essential in meningococcal pathogenesis especially at the blood-brain barrier. This step is likely to involve a common regulatory pathway allowing coordinate regulation...

The Siderophore Receptor IroN, but Not the High-Pathogenicity Island or the Hemin Receptor ChuA, Contributes to the Bacteremic Step of Escherichia coli Neonatal Meningitis

Nègre, Valérie Lefranc, Bonacorsi, Stéphane, Schubert, Soren, Bidet, Philippe, Nassif, Xavier, Bingen, Edouard

Using a neonatal rat meningitis model, we examined the involvement of three iron uptake systems, namely, the high-pathogenicity island, the hemin receptor ChuA, and the siderophore receptor IroN, in...

Culture-Negative Pericarditis Caused by Neisseria meningitidis Serogroup C

Moumile, Kaoutar, Carbonnelle, Etienne, Dessemme, Philippe, Tamisier, Daniel, Iserin, Franck, Houdouin, Véronique, ...

We describe a case of primary purulent culture-negative pericarditis caused by Neisseria meningitidis serogroup C occurring in an 8-month-old previously healthy boy, which was detected in pericardial...

Type IV pilus retraction in pathogenic Neisseria is regulated by the PilC proteins

Morand, Philippe C, Bille, Emmanuelle, Morelle, Sandrine, Eugène, Emmanuel, Beretti, Jean-Luc, Wolfgang, Matthew, ...

Pathogenic Neisseria express type IV pili (tfp), which have been shown to play a central role in the interactions of bacteria with their environment. The regulation of piliation thus constitutes a...

Large-Scale Analysis of the Meningococcus Genome by Gene Disruption: Resistance to Complement-Mediated Lysis

Geoffroy, Marie-Claude, Floquet, Stéphanie, Métais, Arnaud, Nassif, Xavier, Pelicic, Vladimir

The biologic role of a majority of the Neisseria meningitidis 2100 predicted coding regions is still to be assigned or experimentally confirmed. Determining the phenotypic effect of gene disruption...

The meningococcal PilT protein is required for induction of intimate attachment to epithelial cells following pilus-mediated adhesion

Pujol, Céline, Eugène, Emmanuel, Marceau, Michaël, Nassif, Xavier

The ability of Neisseria meningitidis (MC) to interact with cellular barriers is essential to its pathogenesis. With epithelial cells, this process has been modeled in two steps. The initial stage of...

Role of Glycosylation at Ser63 in Production of Soluble Pilin in Pathogenic Neisseria

Marceau, Michael, Nassif, Xavier

Pilus-mediated adhesion is essential in the pathogenesis of Neisseria meningitidis (MC) and Neisseria gonorrhoeae (GC). Pili are assembled from a protein subunit called pilin. Pilin is a...

Identification of Regions of the Chromosome of Neisseria meningitidis and Neisseria gonorrhoeae Which Are Specific to the Pathogenic Neisseria Species

Perrin, Agnes, Nassif, Xavier, Tinsley, Colin

Neisseria meningitidis and Neisseria gonorrhoeae give rise to dramatically different diseases. Their interactions with the host, however, do share common characteristics: they are both human...

Molecular and Biological Analysis of Eight Genetic Islands That Distinguish Neisseria meningitidis from the Closely Related Pathogen Neisseria gonorrhoeae

Klee, Silke R., Nassif, Xavier, Kusecek, Barica, Merker, Petra, Beretti, Jean-Luc, Achtman, Mark, ...

The pathogenic species Neisseria meningitidis and Neisseria gonorrhoeae cause dramatically different diseases despite strong relatedness at the genetic and biochemical levels. N. meningitidis can...

Identification of Regions of the Escherichia coli Chromosome Specific for Neonatal Meningitis-Associated Strains

Bonacorsi, Stéphane Pierre Paul, Clermont, Olivier, Tinsley, Colin, Le Gall, Isabelle, Beaudoin, Jean-Christophe, Elion, Jacques, ...

Specific virulence factors associated with the pathogenesis of Escherichia coli strains causing neonatal meningitis (ECNM), such as the K1 capsular polysaccharide, the S fimbriae, and the Ibe10...

Mutagenesis of Neisseria meningitidis by In Vitro Transposition of Himar1 mariner

Pelicic, Vladimir, Morelle, Sandrine, Lampe, David, Nassif, Xavier

Now that the meningococcal genome sequence has been completed, the lack of a suitable method for saturation mutagenesis remains a major obstacle to the unraveling of the pathogenic propensity of...

A Uropathogenicity Island Contributes to the Pathogenicity of Escherichia coli Strains That Cause Neonatal Meningitis

Houdouin, Véronique, Bonacorsi, Stéphane, Brahimi, Naima, Clermont, Olivier, Nassif, Xavier, Bingen, Edouard

We report that the archetypal Escherichia coli strain C5 causing neonatal meningitis harbors a pathogenicity island (PAI) designated PAI IC5 that is similar to the PAI IIJ96 of uropathogenic E. coli...

Representational Difference Analysis between Afa/Dr Diffusely Adhering Escherichia coli and Nonpathogenic E. coli K-12

Blanc-Potard, Anne-Beatrice, Tinsley, Colin, Scaletsky, Isabel, Le Bouguenec, Chantal, Guignot, Julie, Servin, Alain L., ...

Diffusely adhering Escherichia coli strains harboring Afa/Dr adhesins (Afa/Dr DAEC) have been associated with diarrhea and urinary tract infections (UTIs). The present work is the first extensive...

Comparative Genomics Identifies the Genetic Islands That Distinguish Neisseria meningitidis, the Agent of Cerebrospinal Meningitis, from Other Neisseria Species

Perrin, Agnès, Bonacorsi, Stéphane, Carbonnelle, Etienne, Talibi, Driss, Dessen, Philippe, Nassif, Xavier, ...

Neisseria meningitidis colonizes the nasopharynx and, unlike commensal Neisseria species, is capable of entering the bloodstream, crossing the blood-brain barrier, and invading the meninges. The...

Neisseria meningitidis RTX Proteins Are Not Required for Virulence in Infant Rats

Forman, Stanislav, Linhartova, Irena, Osicka, Radim, Nassif, Xavier, Sebo, Peter, Pelicic, Vladimir

RTX cytotoxins play an important role in virulence of numerous gram-negative pathogens. Unexpectedly, however, we show here that the RTX proteins of Neisseria meningitidis are dispensable for...

The REP2 Repeats of the Genome of Neisseria meningitidis Are Associated with Genes Coordinately Regulated during Bacterial Cell Interaction

Morelle, Sandrine, Carbonnelle, Etienne, Nassif, Xavier

Interaction with host cells is essential in meningococcal pathogenesis especially at the blood-brain barrier. This step is likely to involve a common regulatory pathway allowing coordinate regulation...

The Siderophore Receptor IroN, but Not the High-Pathogenicity Island or the Hemin Receptor ChuA, Contributes to the Bacteremic Step of Escherichia coli Neonatal Meningitis

Nègre, Valérie Lefranc, Bonacorsi, Stéphane, Schubert, Soren, Bidet, Philippe, Nassif, Xavier, Bingen, Edouard

Using a neonatal rat meningitis model, we examined the involvement of three iron uptake systems, namely, the high-pathogenicity island, the hemin receptor ChuA, and the siderophore receptor IroN, in...

Culture-Negative Pericarditis Caused by Neisseria meningitidis Serogroup C

Moumile, Kaoutar, Carbonnelle, Etienne, Dessemme, Philippe, Tamisier, Daniel, Iserin, Franck, Houdouin, Véronique, ...

We describe a case of primary purulent culture-negative pericarditis caused by Neisseria meningitidis serogroup C occurring in an 8-month-old previously healthy boy, which was detected in pericardial...

Type IV pilus retraction in pathogenic Neisseria is regulated by the PilC proteins

Morand, Philippe C, Bille, Emmanuelle, Morelle, Sandrine, Eugène, Emmanuel, Beretti, Jean-Luc, Wolfgang, Matthew, ...

Pathogenic Neisseria express type IV pili (tfp), which have been shown to play a central role in the interactions of bacteria with their environment. The regulation of piliation thus constitutes a...

Large-Scale Analysis of the Meningococcus Genome by Gene Disruption: Resistance to Complement-Mediated Lysis

Geoffroy, Marie-Claude, Floquet, Stéphanie, Métais, Arnaud, Nassif, Xavier, Pelicic, Vladimir

The biologic role of a majority of the Neisseria meningitidis 2100 predicted coding regions is still to be assigned or experimentally confirmed. Determining the phenotypic effect of gene disruption...

Detection and Identification by PCR of a Highly Virulent Phylogenetic Subgroup among Extraintestinal Pathogenic Escherichia coli B2 Strains▿

Bidet, Philippe, Metais, Arnaud, Mahjoub-Messai, Farah, Durand, Lionel, Dehem, Marie, Aujard, Yannick, ...

Closely related Escherichia coli B2 strains O1:K1, O2:K1, O18:K1, and O45:K1 constitute a major subgroup causing extraintestinal infections. A DNA pathoarray analysis was used to develop a PCR...

Identification of Candidates for a Subunit Vaccine against Extraintestinal Pathogenic Escherichia coli▿ †

Durant, Lionel, Metais, Arnaud, Soulama-Mouze, Coralie, Genevard, Jean-Marie, Nassif, Xavier, Escaich, Sonia

Extraintestinal pathogenic Escherichia coli (ExPEC) strains cause a large spectrum of infections. The majority of ExPEC strains are closely related to the B2 or the D phylogenetic group. The aim of...

Rapid Identification of Staphylococci Isolated in Clinical Microbiology Laboratories by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry▿ †

Carbonnelle, Etienne, Beretti, Jean-Luc, Cottyn, Stéphanie, Quesne, Gilles, Berche, Patrick, Nassif, Xavier, ...

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) of intact bacteria yields a reproducible spectrum depending upon growth conditions, strain, or species....

Neisseria meningitidis infection of human endothelial cells interferes with leukocyte transmigration by preventing the formation of endothelial docking structures

Doulet, Nicolas, Donnadieu, Emmanuel, Laran-Chich, Marie-Pierre, Niedergang, Florence, Nassif, Xavier, Couraud, Pierre Olivier, ...

Neisseria meningitidis elicits the formation of membrane protrusions on vascular endothelial cells, enabling its internalization and transcytosis. We provide evidence that this process interferes...

Cerebral microcirculation shear stress levels determine Neisseria meningitidis attachment sites along the blood–brain barrier

Mairey, Emilie, Genovesio, Auguste, Donnadieu, Emmanuel, Bernard, Christine, Jaubert, Francis, Pinard, Elisabeth, ...

Neisseria meningitidis is a commensal bacterium of the human nasopharynx. Occasionally, this bacterium reaches the bloodstream and causes meningitis after crossing the blood–brain barrier by an...

Alternative Neisseria spp. type IV pilin glycosylation with a glyceramido acetamido trideoxyhexose residue

Chamot-Rooke, Julia, Rousseau, Benoit, Lanternier, Fanny, Mikaty, Guillain, Mairey, Emilie, Malosse, Christian, ...

The importance of protein glycosylation in the interaction of pathogenic bacteria with their host is becoming increasingly clear. Neisseria meningitidis, the etiological agent of cerebrospinal...

A chromosomally integrated bacteriophage in invasive meningococci

Bille, Emmanuelle, Zahar, Jean-Ralph, Perrin, Agnes, Morelle, Sandrine, Kriz, Paula, Jolley, Keith A., ...

Cerebrospinal meningitis is a feared disease that can cause the death of a previously healthy individual within hours. Paradoxically, the causative agent, Neisseria meningitidis, is a common...

3D structure/function analysis of PilX reveals how minor pilins can modulate the virulence properties of type IV pili

Helaine, Sophie, Dyer, David H., Nassif, Xavier, Pelicic, Vladimir, Forest, Katrina T.

Type IV pili (Tfp) are widespread filamentous bacterial organelles that mediate multiple virulence-related phenotypes. They are composed mainly of pilin subunits, which are processed before filament...

Activation of ErbB2 receptor tyrosine kinase supports invasion of endothelial cells by Neisseria meningitidis

Hoffmann, Isabelle, Eugène, Emmanuel, Nassif, Xavier, Couraud, Pierre-Olivier, Bourdoulous, Sandrine

ErbB2 is a receptor tyrosine kinase belonging to the family of epidermal growth factor (EGF) receptors which is generally involved in cell differentiation, proliferation, and tumor growth, and...