176
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Vienne P, Ducos-Galand M, Guiyoule A, Pires R, Giorgini D, Taha MK, Alonso JM. The role of particular strains of Neisseria meningitidis in meningococcal arthritis, pericarditis, and pneumonia. Clin Infect Dis 2003; 37:1639-42. [PMID: 14689345 DOI: 10.1086/379719] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2003] [Accepted: 08/11/2003] [Indexed: 11/03/2022] Open
Abstract
The clinical presentations of meningococcal diseases other than meningitis or meningococcemia may lead to erroneous diagnosis. Although several reports have described unusual meningococcal diseases, the Neisseria meningitidis strains involved in these forms have been poorly characterized. In this study, meningococcal arthritis and pericarditis were confirmed by isolation of N. meningitidis and/or detection of meningococcal DNA in synovial or pericardial fluid, respectively, and meningococcal pneumonia was detected by isolation of N. meningitidis from blood. From 1999 through 2002, meningococcal disease was bacteriologically confirmed in 26 cases of arthritis, 6 cases of pericarditis, and 33 cases of pneumonia by the National Reference Center for the Meningococci in Paris. We found a statistically significant association between strains of serogroup W135, mostly of the clonal complex ET-37, and arthritis. Pneumonia was most frequently diagnosed in patients aged >70 years, and 54.5% of the strains belonged to serogroup W135, although these strains had heterogeneous phenotypes. Bacteremia is a key step in the pathophysiology of meningococcal disease and precedes any form of invasive infection.
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177
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Vázquez JA, Arreaza L, Block C, Ehrhard I, Gray SJ, Heuberger S, Hoffmann S, Kriz P, Nicolas P, Olcen P, Skoczynska A, Spanjaard L, Stefanelli P, Taha MK, Tzanakaki G. Interlaboratory comparison of agar dilution and Etest methods for determining the MICs of antibiotics used in management of Neisseria meningitidis infections. Antimicrob Agents Chemother 2003; 47:3430-4. [PMID: 14576098 PMCID: PMC253763 DOI: 10.1128/aac.47.11.3430-3434.2003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2003] [Revised: 06/09/2003] [Accepted: 07/15/2003] [Indexed: 11/20/2022] Open
Abstract
Previous studies have shown that there is considerable variation in the methods and media used to determine the susceptibility of Neisseria meningitidis to antimicrobial agents in different countries. In this study, national and regional reference laboratories used a standardized methodology to determine the MICs of antibiotics used in the management of meningococcal infection. Fourteen laboratories participated in the study, determining the susceptibility to penicillin G, rifampin, cefotaxime, ceftriaxone, ciprofloxacin, and ofloxacin of a collection of 17 meningococci, of which 11 strains were previously defined as having intermediate resistance to penicillin (Pen(I)) by sequencing and restriction fragment length polymorphism analysis of the penA gene. The MIC was determined by agar dilution and Etest with Mueller-Hinton agar (MH), MH supplemented with sheep blood (MH+B), and MH supplemented with heated (chocolated) blood. Several laboratories encountered problems obtaining confluent growth with unsupplemented MH. MH+B was considered to give the most congruent and reproducible results among the study laboratories. The modal MIC for MH+B for each antibiotic and method was calculated to define the MIC consensus, allowing assessment of each individual laboratory's data in relation to the others. The agreement in each antibiotic/method/medium combination was defined as the percentage of laboratories with a result within one dilution of the modal result. For the whole study, an agreement of 90.6% was observed between agar dilution and Etest methods. The agreement in each laboratory/antibiotic/method combination ranged from 98.2% to 69.7%, with six laboratories demonstrating agreement higher than 90% and 11 more than 80%. The ability of the laboratories to detect the Pen(I) isolates ranged from 18.2% to 100%. The apparent difficulty in interpreting susceptibility to rifampin, particularly with the Etest method, is very interesting.
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178
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Zarantonelli ML, Carlier JP, Alonso JM, Taha MK. Erratum to âInsertional inactivation of the lpxAgene involved in the biosynthesis of lipid A in Neisseria meningitidisresulted in lpxA/ lpxA::aph-3â² heterodiploidsâ. FEMS Microbiol Lett 2003. [DOI: 10.1111/rp10.1016-s0378-1097(03)00325-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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179
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Antignac A, Ducos-Galand M, Guiyoule A, Pirès R, Alonso JM, Taha MK. Neisseria meningitidis strains isolated from invasive infections in France (1999-2002): phenotypes and antibiotic susceptibility patterns. Clin Infect Dis 2003; 37:912-20. [PMID: 13130402 DOI: 10.1086/377739] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2003] [Accepted: 05/31/2003] [Indexed: 11/03/2022] Open
Abstract
Infections due to Neisseria meningitidis are a major public health concern. In France, during 1999-2002, a total of 2167 clinical isolates of N. meningitidis from invasive infections were studied at the National Reference Center for Meningococci (Paris). Serogroup B strains were the most common (58%), followed by serogroup C strains (29%) and serogroup W135 strains (8%). Various phenotypes were observed, reflecting heterogeneity in the meningococcal population. Strains were susceptible to antibiotics currently used for treatment and chemoprophylaxis of meningococcal infections. However, the prevalence of meningococci with reduced susceptibility to penicillin is increasing. Such strains were heterogeneous and accounted for approximately 30% of isolates during this period, warranting continued surveillance of this phenomenon.
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180
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Boël G, Mijakovic I, Mazé A, Poncet S, Taha MK, Larribe M, Darbon E, Khemiri A, Galinier A, Deutscher J. Transcription regulators potentially controlled by HPr kinase/phosphorylase in Gram-negative bacteria. J Mol Microbiol Biotechnol 2003; 5:206-15. [PMID: 12867744 DOI: 10.1159/000071072] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Phosphorylation and dephosphorylation at Ser-46 in HPr, a phosphocarrier protein of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) is controlled by the bifunctional HPr kinase/phosphorylase (HprK/P). In Gram-positive bacteria, P-Ser-HPr controls (1) sugar uptake via the PTS; (2) catabolite control protein A (CcpA)-mediated carbon catabolite repression, and (3) inducer exclusion. Genome sequencing revealed that HprK/P is absent from Gram-negative enteric bacteria, but present in many other proteobacteria. These organisms also possess (1) HPr, the substrate for HprK/P; (2) enzyme I, which phosphorylates HPr at His-15, and (3) one or several enzymes IIA, which receive the phosphoryl group from P approximately His-HPr. The genes encoding the PTS proteins are often organized in an operon with HPRK. However, most of these organisms miss CcpA and a functional PTS, as enzymes IIB and membrane-integrated enzymes IIC seem to be absent. HprK/P and the rudimentary PTS phosphorylation cascade in Gram-negative bacteria must therefore carry out functions different from those in Gram-positive organisms. The gene organization in many HprK/P-containing Gram-negative bacteria as well as some preliminary experiments suggest that HprK/P might control transcription regulators implicated in cell adhesion and virulence. In alpha-proteobacteria, HPRK is located downstream of genes encoding a two-component system of the EnvZ/OmpR family. In several other proteobacteria, HPRK is organized in an operon together with genes from the RPON region of ESCHERICHIA COLI (RPON encodes a sigma54). We propose that HprK/P might control the phosphorylation state of HPr and EIIAs, which in turn could control the transcription regulators.
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181
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Antignac A, Boneca IG, Rousselle JC, Namane A, Carlier JP, Vázquez JA, Fox A, Alonso JM, Taha MK. Correlation between alterations of the penicillin-binding protein 2 and modifications of the peptidoglycan structure in Neisseria meningitidis with reduced susceptibility to penicillin G. J Biol Chem 2003; 278:31529-35. [PMID: 12799360 DOI: 10.1074/jbc.m304607200] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Reduced susceptibility to penicillin G in Neisseria meningitidis is directly correlated with alterations in the penA gene, which encodes the penicillin-binding protein 2 (PBP2). Using purified PBP2s from different backgrounds, we confirmed that the reduced susceptibility to penicillin G is associated with a decreased affinity of altered PBP2s for penicillin G. Infrared spectroscopy analysis using isogenic penicillin-susceptible strains and strains with reduced susceptibility to penicillin G suggested that the meningococcal cell wall is also modified in a penA-dependent manner. Moreover, reverse-phase high pressure liquid chromatography and mass spectrometry analysis of these meningococcal strains confirmed the modifications of peptidoglycan components and showed an increase in the peaks corresponding to pentapeptide-containing muropeptides. These results suggest that the D,D-transpeptidase and/or D,D-carboxypeptidase activities of PBP2 are modified by the changes in penA gene.
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182
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Antignac A, Rousselle JC, Namane A, Labigne A, Taha MK, Boneca IG. Detailed structural analysis of the peptidoglycan of the human pathogen Neisseria meningitidis. J Biol Chem 2003; 278:31521-8. [PMID: 12799361 DOI: 10.1074/jbc.m304749200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We used reverse-phase high pressure liquid chromatography (HPLC), matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and post source decay analysis (MALDI-PSD) to determine the muropeptide composition of the human pathogen Neisseria meningitidis. Structural assignment was determined for 28 muropeptide species isolated after HPLC separation and purification. Fourteen of these muropeptides were O-acetylated to different degrees. We identified the entire O-acetylation spectrum of dimers and trimers both in muropeptides and 1,6-anhydromuropeptides. On average, one of three disaccharides was O-acetylated. Furthermore, the degree of cross-linking of the N. meningitidis peptidoglycan was around 39% in all the strains analyzed. MALDI-PSD analysis of several muropeptide species indicated that meningococci only synthesize D-alanyl-meso-diaminopimelate cross-bridges. No muropeptides representative of covalent linkages of lipoproteins to the peptidoglycan could be identified, unlike in Escherichia coli. Finally, comparison of the muropeptide composition of penicillin-susceptible and penicillin-intermediate clinical strains of meningococci showed a positive correlation between the minimum inhibitory concentration (MIC) of penicillin G and the amount of muropeptides carrying an intact pentapeptide chain in the peptidoglycan. This suggests that reduced susceptibility to penicillin G in N. meningitidis is associated with a decrease in d,d-carboxypeptidase activity and/or D,D-transpeptidase activity.
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183
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Girardin SE, Boneca IG, Carneiro LAM, Antignac A, Jéhanno M, Viala J, Tedin K, Taha MK, Labigne A, Zähringer U, Coyle AJ, DiStefano PS, Bertin J, Sansonetti PJ, Philpott DJ. Nod1 detects a unique muropeptide from gram-negative bacterial peptidoglycan. Science 2003; 300:1584-7. [PMID: 12791997 DOI: 10.1126/science.1084677] [Citation(s) in RCA: 1128] [Impact Index Per Article: 53.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Although the role of Toll-like receptors in extracellular bacterial sensing has been investigated intensively, intracellular detection of bacteria through Nod molecules remains largely uncharacterized. Here, we show that human Nod1 specifically detects a unique diaminopimelate-containing N-acetylglucosamine-N-acetylmuramic acid (GlcNAc-MurNAc) tripeptide motif found in Gram-negative bacterial peptidoglycan, resulting in activation of the transcription factor NF-kappaB pathway. Moreover, we show that in epithelial cells (which represent the first line of defense against invasive pathogens), Nod1is indispensable for intracellular Gram-negative bacterial sensing.
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184
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Alonso JM, Guiyoule A, Zarantonelli ML, Ramisse F, Pires R, Antignac A, Deghmane AE, Huerre M, van der Werf S, Taha MK. A model of meningococcal bacteremia after respiratory superinfection in influenza A virus-infected mice. FEMS Microbiol Lett 2003; 222:99-106. [PMID: 12757952 DOI: 10.1016/s0378-1097(03)00252-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
We developed a model of sequential influenza A virus (IAV)-Neisseria meningitidis serogroup C (Nm) infection in BALB/c mice. Mice infected intranasally with a sublethal IAV dose (260 pfu) were superinfected intranasally with Nm. Fatal meningococcal pneumonia and bacteremia were observed in IAV-infected mice superinfected with Nm on day 7, but not in those superinfected on day 10. The susceptibility of mice to Nm superinfection was correlated with the peak interferon-gamma production in the lungs and decrease in IAV load. After Nm challenge, both IAV-infected and uninfected control mice produced the inflammatory cytokines interleukin (IL)-1 and IL-6. However, IL-10 was detected in susceptible mice superinfected on day 7 after IAV infection, but not in resistant mice. This model of dual IAV-Nm infection was also used to evaluate the role of bacterial virulence factors in the synthesis of the capsule. A capsule-defective mutant was cleared from the lungs, whereas a mutant inactivated for the crgA gene, negatively regulating expression of the pili and capsule, upon contact with host cells, retained invasiveness. Therefore, this model of meningococcal disease in adult mice reproduces the pathogenesis of human meningococcemia with fatal sepsis, and is useful for analyzing known or new genes identified in genomic studies.
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185
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Deghmane AE, Larribe M, Giorgini D, Sabino D, Taha MK. Differential expression of genes that harbor a common regulatory element in Neisseria meningitidis upon contact with target cells. Infect Immun 2003; 71:2897-901. [PMID: 12704165 PMCID: PMC153214 DOI: 10.1128/iai.71.5.2897-2901.2003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The expression of several genes in Neisseria meningitidis upon contact with epithelial cells was associated with the presence of the contact regulatory elements of NEISSERIA: These genes are involved in various aspects of meningococcal biology and could be coordinately regulated upon contact with target cells.
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186
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Deghmane AE, Taha MK. The Neisseria meningitidis adhesion regulatory protein CrgA acts through oligomerization and interaction with RNA polymerase. Mol Microbiol 2003; 47:135-43. [PMID: 12492859 DOI: 10.1046/j.1365-2958.2003.03259.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
CrgA is a LysR-type transcriptional regulator involved in the intimate adhesion of Neisseria meningitidis to target human epithelial cells. It is negatively autoregulated, and its expression is transiently induced upon contact with target cells. We analysed the functional organization of CrgA using in frame deleted proteins. Four truncated proteins were constructed and purified. They were deleted between residues 20 and 40, 121 and 154, 111 and 181 and 268 and 291. Meningococcal mutants harbouring the corresponding deleted crgA alleles were also constructed. All mutants showed a reduced ability to adhere to epithelial cells. beta-Galactosidase activity assays using a crgA-lacZ transcriptional fusion showed that all the mutations except the 268-291 deletion resulted in loss of induction upon contact with target cells. Gel mobility shift assays and cross-linking assays showed that the oligomerization of CrgA is required for DNA binding and that the N-terminal part of CrgA is directly involved in DNA binding through a helix-turn-helix motif. The C-terminal region is also involved in DNA binding, probably by permitting the oligomerization of CrgA. The C-terminal region also seemed to interact with RNA polymerase. Therefore, the binding of CrgA and its interaction with RNA polymerase may inhibit the clearance of meningococcal promoters that are repressed by CrgA during the intimate adhesion of N. meningitidis to target cells.
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187
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du Châtelet IP, Alonso JM, Taha MK. [Clonal expansion of Neisseria meningitidis W135. Epidemiological implications for the African meningitis belt]. BULLETIN DE LA SOCIETE DE PATHOLOGIE EXOTIQUE (1990) 2002; 95:323-4; discussion 324-5. [PMID: 12696368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
Meningococcal meningitis occur as large epidemics in the "African meningitis belt" described by L. Lapeyssonnie. Neisseria meningitidis serogroup A, clone III-I, was involved in recent epidemics and immunization with A and C vaccine was therefore adequate. However, we report here the emergence of a new clone of N. meningitidis of serogroup W135 during the 2001 epidemics in Niger and in Burkina Faso and discuss the implications of this new epidemiological feature for future surveillance and vaccine strategies.
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188
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Taha MK, Deghmane AE, Antignac A, Zarantonelli ML, Larribe M, Alonso JM. The duality of virulence and transmissibility in Neisseria meningitidis. Trends Microbiol 2002; 10:376-82. [PMID: 12160636 DOI: 10.1016/s0966-842x(02)02402-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neisseria meningitidis is a commensal bacterium of the human nasopharynx that occasionally provokes invasive disease. Carriage strains of N. meningitidis are heterogeneous, more frequent in nature and are transmitted among carriers. Disease is not a part of this transmission cycle and is caused by virulent strains. N. meningitidis is highly variable and variants that are modified in their virulence and/or transmissibility are continually generated. These events probably occur frequently, thus explaining not only the heterogeneous nature of meningococcal populations in carriers but probably also the evolutionary success of this human-restricted bacterium.
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189
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Mayer LW, Reeves MW, Al-Hamdan N, Sacchi CT, Taha MK, Ajello GW, Schmink SE, Noble CA, Tondella MLC, Whitney AM, Al-Mazrou Y, Al-Jefri M, Mishkhis A, Sabban S, Caugant DA, Lingappa J, Rosenstein NE, Popovic T. Outbreak of W135 meningococcal disease in 2000: not emergence of a new W135 strain but clonal expansion within the electophoretic type-37 complex. J Infect Dis 2002; 185:1596-605. [PMID: 12023765 DOI: 10.1086/340414] [Citation(s) in RCA: 180] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2001] [Revised: 01/07/2002] [Indexed: 11/03/2022] Open
Abstract
In 2000, >400 cases of disease caused by Neisseria meningitidis serogroup W135 (MenW135), the largest MenW135 outbreak reported to date, occurred worldwide among Hajj pilgrims and their contacts. To elucidate the origin of the outbreak strains and to investigate their relatedness to major clonal groups, genotypic and phenotypic subtyping was performed on 26 MenW135 outbreak-associated isolates and 50 MenW135 isolates collected worldwide from 1970 through 2000. All outbreak-associated isolates were members of a single clone of the hypervirulent electrophoretic type (ET)-37 complex, designated the "(W)ET-37 clone"; 19 additional MenW135 strains were also members of this clone, and the remaining 31 MenW135 strains were clearly distinct. The 2000 MenW135 outbreak was not caused by emergence of a new MenW135 strain but rather by expansion of the (W)ET-37 clone that has been in circulation at least since 1970; the strains most closely related to those causing the 2000 outbreak have been isolated in Algeria, Mali, and The Gambia in the 1990s.
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190
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Fonkoua MC, Taha MK, Nicolas P, Cunin P, Alonso JM, Bercion R, Musi J, Martin PMV. Recent increase in meningitis Caused by Neisseria meningitidis serogroups A and W135, Yaoundé, Cameroon. Emerg Infect Dis 2002; 8:327-9. [PMID: 11927034 PMCID: PMC2732466 DOI: 10.3201/eid0803.010308] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
From 1991 to 1998, Neisseria meningitidis serogroups A, B, and C represented 2%-10% of strains isolated from cases of bacterial meningitis in Yaoundé. During 1999 to 2000, the percentage of meningococci reached 17%, a proportion never reported since recordkeeping began in 1984. The increase of serogroup A meningococci and the emergence of W135 strains highlight the need for increased surveillance for better diagnosis and prevention.
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191
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Abstract
Immediate management of meningococcal infections is a medical emergency that requires rapid identification and typing of bacterial strains. Isolation of Neisseria meningitidis is hindered by early antibiotic treatment. Molecular (nonculture) methods of diagnosis and characterization of N. meningitidis permit to overcome this failure. This bacterium is highly variable due to frequent horizontal DNA exchange between strains. Molecular approaches of typing allow a reliable tracking of meningococcal strains and a powerful epidemiological analysis.
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192
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Deghmane AE, Giorgini D, Larribe M, Alonso JM, Taha MK. Down-regulation of pili and capsule of Neisseria meningitidis upon contact with epithelial cells is mediated by CrgA regulatory protein. Mol Microbiol 2002; 43:1555-64. [PMID: 11952904 DOI: 10.1046/j.1365-2958.2002.02838.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The initial attachment of Neisseria meningitidis to the target cell surface appears to be largely pilus depend-ent in capsulated bacteria. Intimate adhesion subsequently occurs to permit colonization. We recently reported that insertional inactivation of the crgA gene, which encodes a transcriptional regulator belonging to the LysR family, decreased meningococcal adhesion to epithelial cells and abolished intimate adhesion. In this report, we analyse expression of the pilE and sia genes, which are involved in the biosynthesis of pili and capsule respectively, during bacteria-host cell interactions. Western blotting, transcriptional fusion and reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed that the expression of these genes was downregulated during intimate adhesion. DNA-binding assays, footprinting and RT-PCR analysis indicated that this downregulation was directly mediated by the CrgA protein. The pilE and sia promoters were found to have a CrgA binding motif in common. These results strongly suggest that N. meningitidis displays an adaptive response upon cell contact. CrgA may play a central regulatory role in meningococcal adhesion, particularly in switching from initial to intimate adhesion by downregulating the bacterial surface structures that hinder this adhesion.
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193
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Taha MK, Parent Du Chatelet I, Schlumberger M, Sanou I, Djibo S, de Chabalier F, Alonso JM. Neisseria meningitidis serogroups W135 and A were equally prevalent among meningitis cases occurring at the end of the 2001 epidemics in Burkina Faso and Niger. J Clin Microbiol 2002; 40:1083-4. [PMID: 11880446 PMCID: PMC120283 DOI: 10.1128/jcm.40.3.1083-1084.2002] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Meningococcal infections occur as epidemics in the African meningitis belt. Neisseria meningitidis serogroup A is predominantly involved in these epidemics. We report here new data on the involvement of both serogroups A and W135 in meningitis cases in Burkina Faso and Niger at the end of the 2001 epidemic.
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194
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Antignac A, Alonso JM, Taha MK. Nonculture prediction of Neisseria meningitidis susceptibility to penicillin. Antimicrob Agents Chemother 2001; 45:3625-8. [PMID: 11709355 PMCID: PMC90884 DOI: 10.1128/aac.45.12.3625-3628.2001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We developed a nonculture method to predict the susceptibility of Neisseria meningitidis to penicillin G. The penA gene was amplified and submitted to restriction fragment length polymorphism analysis. This approach was first validated with a collection of 75 meningococcal strains of known phenotypes. It was next successfully applied to 29 clinical samples.
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195
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Matsika-Claquin MD, Perrocheau A, Taha MK, Levy-Bruhl D, Renault P, Alonso JM, Desenclos JC. [Meningococcal W135 infection epidemics associated with pilgrimage to Mecca in 2000]. Presse Med 2001; 30:1529-34. [PMID: 11721491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVES On April 3 and 7, 2000, four cases of Neisseria meningitidis serogroup W135 infection were diagnosed in France in Raj pilgrims and their close relatives. Two cases were fatal. Due to the rarity of this strain in France, a strain belonging to a clonal complex implicated in several epidemics in Europe and North America, and it high mortality observed, The French General Direction of Heal issued recommendations on April 8th for rifampicin chemotherapy for all pilgrims and relatives living in their home. The national disease watch (Institut de Veille Sanitaire, InVS) conducted an investigation to describe the epidemic and follow the diffusion of the strain in the population and assess the impact of preventive measures taken as well as need for other specific measures. METHODS A case was considered to be confirmed when the strain isolated from usually sterile media after March 22 was found to be identical to the epidemic strain (W135, 2a: P1-2.5--clonal complex ET37). A case was considered probable when a pilgrim or in a person in contact with a pilgrim had clinical meningitis (purulent cerebrospinal fluid or purpura fulminans) or when the identified strain was in the W135 serogroup but could not be further identified. A standardized questionnaire developed in collaboration with the European countries concerned by the epidemic was filled out. RESULTS By November 20, 2000, 25 confirmed and 2 probable cases were identified; 85% of the cases occurred during the first 7 weeks of the epidemic. Mortality was 18%. Patients aged over 50 years accounted for 66% of the cases (6/9) occurring before April 9, 2000 and 17% of the cases (3/18) observed after this data. Four patients had single-joint arthritis. No cluster cases could be identified. Four cases occurred among 19,100 pilgrims (attack rate 21/100,000), 9 among persons living with pilgrims, 7 among subjects in direct contact with pilgrims but not living with them, and 7 among persons who had no identifiable contact with pilgrims. These last 7 cases occurred after the 3rd week of the epidemic. No cases occurred among persons who had taken rifampicin chemoprophylaxis. Eighteen cases occurred after diffusion of the prophylaxis recommendations including 5 in a population directly concerned by the recommendations. CONCLUSIONS These data suggest that the epidemic strain is not different from other strains in terms of virulence and transmissibility. Eight months after the Raj, the number of cases related to the epidemic remained limited in France. The characteristics of the most recent cases do however suggest an epidemic clone persists in the general population. The Direction of Health recommends vaccination using the quadrivalent A,C,W135,Y vaccine for the 2001 Raj.
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196
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Taha MK, Antignac A, Renault P, Perrocheau A, Levy-bruhl D, Nicolas P, Alonso JM. [Clonal spread of Neisseria meningitidis W135]. Presse Med 2001; 30:1535-8. [PMID: 11721492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVES Efficient surveillance of communicable diseases involves dose collaboration between physicians, epidemiologist and bacteriologists. The characterization of meningococcal infections is a medical emergency due to their lethality and their epidemic behavior. The recent expansion of Neisseria meningitidis of serogroup W135 among pilgrims and their contacts underlines the need of a multidisciplinary procedure of alert. METHODS Meningococcal strains are usually received by the National Reference Center for Meningococci (CNRM). They are identified and then typed to determine their antigenic formula (serogroup:serotype:serosubtype). For cluster analysis, the CNRM as well as the WHO collaborating center, perform molecular typing of isolated strains. Should an epidemic is suspected, the institut de Veille Sanitaire and the Direction Générale de la Santé are immediately informed. RESULTS Between the 22th of March and the 20th of November 2000, 27 cases of systemic meningococcal infections due to N. meningitidis of the antigenic formula W135:2a:P1-2.5 were identified. Molecular typing of these strains showed that they were clonal and belonged to the complex ET-37. The dissemination of this clone among pilgrims who were vaccinated against serogroups A and C may suggest the selection of a new variant by an escape alteration in the capsule. However, such strains were detected in France as early as 1994. CONCLUSION The global spread of N. meningitidis of serogroup W135 belonging to the ET-37 clonal complex should be kept under a close surveillance since epidemics may occur particularly in Africa. New vaccination procedures (quadrivalent vaccines and multivalent conjugate meningococcal vaccines) are therefore needed.
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Taha MK, Bichier E, Perrocheau A, Alonso JM. Circumvention of herd immunity during an outbreak of meningococcal disease could be correlated to escape mutation in the porA gene of Neisseria meningitidis. Infect Immun 2001; 69:1971-3. [PMID: 11179386 PMCID: PMC98115 DOI: 10.1128/iai.69.3.1971-1973.2001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Meningococcal strains isolated during an outbreak were shown to belong to the ET-5 complex and to harbor a mutation in the VR2 region of the porA gene. They were less susceptible to the bactericidal effect of normal human serum than was the ET-5 wild-type strain. These results are of concern, as PorA is a potential target in vaccine design.
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Antignac A, Kriz P, Tzanakaki G, Alonso JM, Taha MK. Polymorphism of Neisseria meningitidis penA gene associated with reduced susceptibility to penicillin. J Antimicrob Chemother 2001; 47:285-96. [PMID: 11222561 DOI: 10.1093/jac/47.3.285] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We studied polymorphism of penA (which encodes penicillin-binding protein 2) in 13 strains of Neisseria meningitidis susceptible to penicillin (pen(S)) and 12 strains with reduced susceptibility to penicillin (pen(I)). These strains differed in geographical origin. Serological and genetic typing showed that they were highly diverse and belonged to several genetic lineages. Restriction analysis and DNA sequencing of penA showed that all pen(S) strains had the same penA allele regardless of genetic group, whereas pen(I) strains harboured various penA alleles. Transformation with amplicons of penA and genomic DNA from several pen(I) strains conferred the pen(I) phenotype on a pen(S) strain. Thus, reduction in susceptibility to penicillin is directly related to changes in penA and analysis of penA polymorphisms could be used as a reliable tool for characterizing meningococcal strains in terms of their susceptibility to penicillin.
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Taha MK, Achtman M, Alonso JM, Greenwood B, Ramsay M, Fox A, Gray S, Kaczmarski E. Serogroup W135 meningococcal disease in Hajj pilgrims. Lancet 2000; 356:2159. [PMID: 11191548 DOI: 10.1016/s0140-6736(00)03502-9] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
An outbreak of W135 meningococcal disease occurred in the spring of 2000 among pilgrims returning from Saudi Arabia and their contacts. Clinical isolates from England and France were examined and compared with reference strains from other countries. Characterisation of isolates by a range of typing methods showed them to be of clonal origin (ET-37) and closely related to other meningococci with an established propensity to cause disease clusters. A reappraisal of vaccination strategies for travellers is required.
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Deghmane AE, Petit S, Topilko A, Pereira Y, Giorgini D, Larribe M, Taha MK. Intimate adhesion of Neisseria meningitidis to human epithelial cells is under the control of the crgA gene, a novel LysR-type transcriptional regulator. EMBO J 2000; 19:1068-78. [PMID: 10698947 PMCID: PMC305645 DOI: 10.1093/emboj/19.5.1068] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PilC1, a pilus-associated protein in Neisseria menin- gitidis, is a key element in initial meningococcal adhesion to target cells. A promoter element (CREN, contact regulatory element of Neisseria) is responsible for the transient induction of this gene upon cell contact. crgA (contact-regulated gene A) encodes a transcriptional regulator whose expression is also induced upon cell contact from a promoter region similar to the CREN of pilC1. CrgA shows significant sequence homologies to LysR-type transcriptional regulators. Its inactivation in meningococci provokes a dramatic reduction in bacterial adhesion to epithelial cells. Moreover, this mutant is unable to undergo intimate adhesion to epithelial cells or to provoke effacing of microvilli on infected cells. Purified CrgA is able to bind to pilC1 and crgA promoters, and CrgA seems to repress the expression of pilC1 and crgA. Our results support a dynamic model of bacteria-cell interaction involving a network of regulators acting in cascade. CrgA could be an intermediate regulator in such a network.
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