Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “NEISSERIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1993

Relatedness of three species of "false neisseriae," Neisseria caviae, Neisseria cuniculi, and Neisseria ovis, by DNA-DNA hybridizations and fatty acid analysis.

DNA-DNA hybridization was used to determine the levels of genomic relatedness of the three species of "false neisseriae," Neisseria caviae, Neisseria cuniculi, and Neisseria ovis. The reference strains of these species exhibited high levels of intraspecies relatedness (93 to 100% for N. caviae, 79 to 100% for N. cuniculi, and 68 to 100% for N. ovis) but low levels of interspecific relatedness (less than 34%) to each other and to various species belonging to the beta subclass of the Proteobacteria (Kingella kingae, Neisseria gonorrhoeae, Neisseria meningitidis, and Oligella urethralis) or to the gamma subclass (Branhamella catarrhalis, Kingella indologenes, Moraxella atlantae, Moraxella bovis, Moraxella lacunata subsp. lacunata, Moraxella lacunata subsp. liquefaciens, Moraxella nonliquefaciens, Moraxella osloensis, and Moraxella phenylpyruvica). However, the levels of DNA-DNA hybridization for the three species of "false neisseriae" were significantly higher with the species belonging to the gamma subclass (average, 13.7%) than with the species belonging to the beta subclass (average, 4.5%). These data suggest that N. caviae, N. cuniculi, and N. ovis are three separate genomic species in the gamma subclass. An ascendant hierarchical classification based only on fatty acid profiles distinguished four main classes containing (i) most of the "classical moraxellae," the "false neisseriae," and B. catarrhalis, (ii) only Acinetobacter spp., (iii) M. nonliquefaciens and "misnamed moraxellae" (M. atlantae, M. osloensis, and M. phenylpyruvica), and (iv) the "true neisseriae," the three Kingella species, and O. urethralis. Fatty acids that distinguish these four classes were identified. The fatty acid profiles of the two strains of Psychrobacter immobilis which we studied are not very similar to the profiles of the other taxa. Our results support the hypothesis that the three species of "false neisseriae," B. catarrhalis, the "classical moraxellae," and Acinetobacter spp. should be included in the same family.

Bacterial Typing Techniques↗
PubMed1989

Identification of epitopes recognized by monoclonal antibodies SM1 and SM2 which react with all pili of Neisseria gonorrhoeae but which differentiate between two structural classes of pili expressed by Neisseria meningitidis and the distribution of their encoding sequences in the genomes of Neisseria spp.

The pili expressed by all isolates of Neisseria gonorrhoeae react with two monoclonal antibodies, SM1 and SM2. In contrast, although many isolates of Neisseria meningitidis also express pili (class I) which react with antibodies SM1 and SM2, a proportion express pili (class II) which fail to react. In order to define the epitopes recognized by these antibodies, a series of overlapping peptides corresponding to the amino acid sequence of conserved regions of gonococcal pili have been synthesized. The minimum epitope recognized by antibody SM1 was found to comprise a linear peptide EYYLN, corresponding to residues 49-53 of mature pilin. In contrast, antibody SM2 reacted with a number of peptides from around the cysteine residue (Cys 1) at position 120, suggesting that an extended region may contribute to a conformational epitope recognized by this antibody in the native protein. The identification of the two epitopes defines structural differences between the classes of pili expressed by meningococci. In order to determine the distribution of pilin gene sequences in Neisseria we used as hybridization probes an oligonucleotide (PS1) with the sequence 5'-GAGTATTACCTGAATCA-3' which spans the coding region for the SM1 epitope, and a fragment of the 3' end of the gonococcal pilE gene which contains conserved sequences flanking the two Cys codons and encodes the SM2 epitope. All strains of N. gonorrhoeae and N. meningitidis tested, regardless of piliation phenotype, harboured DNA sequences homologous to those encoding the carboxy-terminus of meningococcal class I pilin. Furthermore, all gonococci and all meningococci producing class I pili hybridized with oligonucleotide probe PS1. Non-reverting non-piliated derivatives of previously class I pilus-producing strains showed reduced hybridization signals with this probe, but nevertheless retained sequences homologous to the coding sequence for the SM1 epitope. However, meningococci producing class II pili could be divided into two groups on the basis of their reaction with the PS1 probe: half the strains tested failed to react, which is consistent with our previous analysis of silent class I pilin sequences; the remainder reacted (relatively weakly) with the probe, suggesting that the silent pil sequences in these strains extend further towards the 5' end of the pilin gene than in strains studied previously. Some strains of Neisseria lactamica reacted weakly with both types of probe but failed to produce SM1-reactive pili. In contrast, isolates of Neisseria flava, Neisseria pharyngis, Neisseria sicca and a series of unrelated bacteria failed to react with both SM1 antibody and the DNA probes. This confirms that possession of 'gonococcal' pilin sequences is limited to the pathogenic neisseriae.

Amino Acid Sequence↗
PubMed1981

Ability of Neisseria gonorrhoeae, Neisseria meningitidis, and commensal Neisseria species to obtain iron from transferrin and iron compounds.

The ability of Neisseria species to use iron compounds and to compete with iron-binding proteins was examined with deferrated defined medium and the iron chelator deferoxamine. All Neisseria species were able to assimilate a variety of ferric and ferrous iron salts. They were not able to efficiently solubilize an inorganic iron salt such as ferric nitrate, but were able to use iron chelated by citrate, oxalacetate, pyrophosphate, or nitrilotriacetate. Each of the 95 Neisseria isolates examined was able to use hemin as a sole source of iron, and most, but not all, of the isolates were able to obtain iron from hemoglobin. Heated human serum stimulated growth of all gonococci, meningococci, and some commensal Neisseria species in iron-deficient medium. All gonococci and meningococci were able to scavenge iron from 25% saturated transferrin, whereas most commensal organisms were inhibited by this iron-binding protein. The ability to compete with transferrin was specific, since partially saturated conalbumin was bacteriostatic for all Neisseria species. Although the pathogenic Neisseria species were able to compete more efficiently with transferrin for iron than were the nonpathogenic Neisseria species, no correlation was observed between the virulence of different strains or colony types of gonococci and the ability to scavenge iron in vitro from transferrin or other chelators.

Blood↗
PubMed1999

Identification of regions of the chromosome of Neisseria meningitidis and Neisseria gonorrhoeae which are specific to the pathogenic Neisseria species.

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 pathogens which do not survive in the environment and which colonize and invade mucosa at their port of entry. It is therefore likely that they have common properties that might not be found in nonpathogenic bacteria belonging to the same genetically related group, such as Neisseria lactamica. Their common properties may be determined by chromosomal regions found only in the pathogenic Neisseria species. To address this issue, we used a previously described technique (C. R. Tinsley and X. Nassif, Proc. Natl. Acad. Sci. USA 93:11109-11114, 1996) to identify sequences of DNA specific for pathogenic neisseriae and not found in N. lactamica. Sequences present in N. lactamica were physically subtracted from the N. meningitidis Z2491 sequence and also from the N. gonorrhoeae FA1090 sequence. The clones obtained from each subtraction were tested by Southern blotting for their reactivity with the three species, and only those which reacted with both N. meningitidis and N. gonorrhoeae (i.e., not specific to either one of the pathogens) were further investigated. In a first step, these clones were mapped onto the chromosomes of both N. meningitidis and N. gonorrhoeae. The majority of the clones were arranged in clusters extending up to 10 kb, suggesting the presence of chromosomal regions common to N. meningitidis and N. gonorrhoeae which distinguish these pathogens from the commensal N. lactamica. The sequences surrounding these clones were determined from the N. meningitidis genome-sequencing project. Several clones corresponded to previously described factors required for colonization and survival at the port of entry, such as immunoglobulin A protease and PilC. Others were homologous to virulence-associated proteins in other bacteria, demonstrating that the subtractive clones are capable of pinpointing chromosomal regions shared by N. meningitidis and N. gonorrhoeae which are involved in common aspects of the host interaction of both pathogens.

Chromosomes, Bacterial↗
PubMed1986

Homology of cryptic plasmid of Neisseria gonorrhoeae with plasmids from Neisseria meningitidis and Neisseria lactamica.

DNA probe hybridisation was used to examine the relation between the cryptic plasmid from Neisseria gonorrhoeae and plasmids carried by pharyngeal isolates of Neisseria meningitidis and Neisseria lactamica. The complete gonococcal cryptic plasmid and HinfI derived digestion fragments subcloned into Escherichia coli were used to probe Southern blots of plasmid extracts. Homology was found to a plasmid of approximate molecular weight 4.5 kilobase pairs (Kb) but not to plasmids of less than 3.2 Kb or 6.5 Kb. Eleven of 16 strains of N meningitidis and two of six strains of N lactamica carried plasmids that showed strong hybridisation with the 4.2 Kb gonococcal plasmid. Hybridisation of plasmids from non-gonococcal species of neisseria with the gonococcal cryptic plasmid indicates that caution should be taken when using the cryptic plasmid as a diagnostic probe for gonorrhoea.

DNA, Bacterial↗
PubMed1988

Transfer of beta-lactamase plasmids from Neisseria gonorrhoeae to Neisseria meningitidis and commensal Neisseria species by the 25.2-megadalton conjugative plasmid.

Two highly tetracycline-resistant, beta-lactamase-producing Neisseria gonorrhoeae strains were used as donors for conjugation with Neisseria meningitidis and commensal Neisseria species. We found that both strains were able to transfer the 4.4- and 3.2-megadalton beta-lactamase plasmids to the recipients tested, with frequencies between 10(-1) and 10(-9).

Conjugation, Genetic↗
PubMed1982

Ability of Neisseria gonorrhoeae, Neisseria meningitidis, and commensal Neisseria species to obtain iron from lactoferrin.

The ability of 107 Neisseria isolates to compete for iron with human lactoferrin (LF) was examined. Each of 15 meningococci, 53% of 59 selected gonococci, and 24% of 33 commensal Neisseria could use LF-bound iron for growth. Isolates which could not obtain iron from LF were growth inhibited when sufficient LF was added to defined agar medium to bind available free iron. No difference was observed in the ability of colony type 1 and colony type 4 gonococci of the same strain to compete with LF for iron. LF was growth inhibitory for 50% of 22 disseminated disease isolates (DGI strains) and 51% of 35 local urogenital disease isolates (UGI strains). Only 14% of gonococcal isolates requiring arginine, hypoxanthine, and uracil for growth were able to compete with LF for iron, whereas 87% of all other gonococcal isolates could do so (P less than 0.005). Ability to obtain iron from LF does not appear to be required for survival of Neisseria on mucosal surfaces, nor essential for invasion of the bloodstream by gonococci. However, ability to utilize LF as a source of iron may contribute to differences in pathogenicity among certain gonococcal isolates.

Fimbriae, Bacterial↗
PubMed1985

Difficulties in differentiating Neisseria cinerea from Neisseria gonorrhoeae in rapid systems used for identifying pathogenic Neisseria species.

Neisseria cinerea and Neisseria gonorrhoeae may occur at the same body sites and may have similar colony morphologies. Ideally, systems used for rapid identification of N. gonorrhoeae should be able to differentiate N. cinerea from gonococci. We tested seven N. cinerea strains using the Gonochek II (Du Pont Diagnostics), Minitek (BBL Microbiology Systems), RapID-NH (Innovative Diagnostics, Inc.), RIM-N (American Microscan), and Phadebact (Pharmacia Diagnostics) systems. We found that the reactions produced by N. cinerea in Gonochek II, Minitek, and RapID-NH kits could be confused with the results produced by some strains of N. gonorrhoeae. The susceptibility of N. cinerea to colistin, its ability to grow on tryptic soy or Mueller-Hinton agar, and its inability to grow on modified Thayer-Martin medium help differentiate it from gonococci.

Microbiological Techniques↗
PubMed2005

Antimicrobial activity of LBM415 (NVP PDF-713) tested against pathogenic Neisseria spp. (Neisseria gonorrhoeae and Neisseria meningitidis).

LBM415 (NVP PDF-713), a novel peptide deformylase inhibitor, was tested by reference methods against 2 collections of pathogenic Neisseria, N. gonorrhoeae (157 strains) and N. meningitidis (100 strains). The collection included strains resistant to penicillin, tetracycline, and fluoroquinolones and were also tested against ceftriaxone, ciprofloxacin, penicillin, and tetracycline. The 50% and 90% minimum inhibitory concentration values for LBM415 were 1 and 2 microg/mL, and 4 and 8 microg/mL for N. meningitidis and N. gonorrhoeae, respectively. All comparison agents were more active than this peptide deformylase inhibitor against this genus.

Anti-Bacterial Agents↗
PubMed2000

Novel genus-specific PCR-based assays for rapid identification of Neisseria species and Neisseria meningitidis.

This study presents the development of polymerase chain reaction (PCR)-based tests for the identification and detection of Neisseria species and Neisseria meningitidis. Currently, isolating and identifying these pathogens using conventional biochemical methods require 48-72 h. To improve speed and accuracy in diagnosing Neisseria infections, simple PCR-based tests that are specific for the genus Neisseria and the species Neisseria meningitidis have been developed. The genus-specific and species-specific DNA sequences were chosen by selecting and analyzing available database sequences. Neisseria-specific and Neisseria meningitidis-specific primer pairs were derived from the genes asd (coding for the aspartate beta-semialdehyde dehydrogenase) and ctrA (coding for a conserved outer membrane protein), respectively. Both the Neisseria-specific and Neisseria meningitidis-specific PCR assays were specific (they amplified only DNA from the target genus or species, out of 84 bacterial species tested). In addition, the Neisseria-specific assay amplified DNA from 321 of 322 strains tested representing 13 species of Neisseria, while the Neisseria meningitidis-specific assay amplified DNA from all 256 strains tested representing nine serogroups of Neisseria meningitidis. These PCR assays, which can be combined in multiplex, have been adapted to ensure that they are simple and can be performed within approximately 90 min. The tests provide new diagnostic tools for identifying Neisseria infections.

Aspartate-Semialdehyde Dehydrogenase↗
PubMed2002

Evaluation of the BactiCard Neisseria for identification of pathogenic Neisseria species and Moraxella catarrhalis.

The BactiCard Neisseria (Remel, USA) is a chromogenic enzyme substrate system for identifying Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria lactamica, and Moraxella catarrhalis. The identification system consists of a card with four test circles impregnated with chromogenic substrates for indoxyl butyrate esterase (IB), prolyl aminopeptidase (PRO), gamma-glutamyl aminopeptidase (GLUT), and ss-galactosidase (BGAL). These substrates permit the identification of Moraxella catarrhalis, Neisseria gonorrhoeae, Neisseria meningitidis, and Neisseria lactamica, respectively. After hydration of the circles with buffer, colonies from growth on selective media or a subculture are applied to the four circles. IB and BGAL reactions are read for a blue-green color after 2 and 15 min, respectively. PRO and GLUT reactions are read at 15 min for a red color after addition of a developer reagent. Identifications obtained with the BactiCard Neisseria were compared with those obtained using conventional procedures for 558 isolates in a blinded fashion. The BactiCard Neisseria identified 100% of 254 Neisseria gonorrhoeae, 100% of 125 Neisseria meningitidis, 53 (98.2%) of 54 Neisseria lactamica, and 123 (98.4%) of 125 Moraxella catarrhalis isolates. The BactiCard Neisseria is an accurate and rapid system for identification of these microorganisms in the clinical laboratory.

Bacterial Typing Techniques↗
PubMed1998

[Factors affecting Neisseria meningitidis and Neisseria lactamica carrier state].

Invasive meningococcal diseases have become in the Czech Republic since 1993 a serious epidemiological and clinical problem due to a clonus which was not present previously: Neisseria meningitidis C:2a:P1.2,P1.5, ET-15/37. In 1996 a trial was conducted focused on the problem how this altered epidemiological and clinical situation is reflected in carriership of Neisseria meningitidis and Neisseria lactamica in the healthy population. Two age groups were followed up which were most severely affected by the new clonus of the meningococcus: 15-19 years (410 subjects) and 1-4 years (116 subjects). The trial was implemented in Olomouc where in 1993 the new epidemiological situation of the incidence of the invasive meningococcal disease was so serious that targeted vaccination was introduced. Of 116 children in the age group from 1-4 years in none Neisseria meningitidis was detected, in 9 Neisseria lactamica was found (7.7%). On repeated examination of children with a positive cultivation of Neisseria lactamica after two weeks in none Neisseria meningitidis nor Neisseria lactamica were found. Of 410 subjects in the age group from 15-19 years in none Neisseria lactamica was detected and in 35 Neisseria meningitidis (8.5%). Examinations were repeated after two weeks in 33 carriers: in 31 Neisseria meningitidis was again cultivated. Analysis of factors influencing carriership revealed in Neisseria lactamica two factors in young children which significantly promote this carriership: cold and close contact/kissing. A risk factor at the limit of significance are frequent respiratory diseases. In the carriership of Neisseria meningitidis in 15-19 year-old subjects six factors were revealed which promote carriership. A significant risk factor is close contact/kissing, the existence of partnership, participation in activities of the "disco" type, living in a town, flats in the centre of the town. Effort is a risk factor at the limit of significance.

Adolescent↗
PubMed1984

Conjugation of plasmids of Neisseria gonorrhoeae to other Neisseria species: potential reservoirs for the beta-lactamase plasmid.

The discovery that penicillinase production in Neisseria gonorrhoeae was plasmid mediated and the spread of the beta-lactamase encoding plasmids in gonococcal isolates since 1976, raise the possibility that a nonpathogenic indigenous bacterium could serve as a reservoir for these plasmids. We initiated studies to define the ability of commensal Neisseria species and Branhamella catarrhalis strains, as well as strains of the pathogen Neisseria meningitidis, to serve as recipients in conjugation with Neisseria gonorrhoeae. We found that with N. gonorrhoeae as the donor, 3 of 5 Neisseria cinerea, 2 of 5 Neisseria flava, 0 of 1 Neisseria flavescens, 1 of 3 Neisseria subflava, 0 of 6 B. catarrhalis, 0 of 7 Neisseria lactamica, 1 of 5 Neisseria mucosa, 1 of 7 Neisseria perflava/sicca, and 0 of 13 N. meningitidis strains gave detectable conjugation frequencies (greater than 10(-8). N. cinerea was the only species found to maintain the gonococcal conjugal plasmid (pLE2451). A N. cinerea transconjugant containing pLE2451 was observed to transfer both the beta-lactamase plasmid and pLE2451 to N. gonorrhoeae at high frequency.

Conjugation, Genetic↗
PubMed1993

Analysis in Neisseria meningitidis and other Neisseria species of genes homologous to the FKBP immunophilin family.

The immunophilin family of FK506-binding proteins (FKBPs), involved in eukaryotic protein-folding and cell regulation, have recently been found to have prokaryotic homologues. Genes with sequences homologous to those encoding human FKBPs were examined in Neisseria species. An FKBP DNA sequence was present, as shown by the polymerase chain reaction and Southern blotting experiments, in the chromosome of Neisseria meningitidis (14 strains) and in all 11 different commensal Neisseria spp. studied, but was not found in Neisseria gonorrhoeae (11 strains tested) or in Moraxella catarrhalis. The nucleotide and predicted protein sequences of the FKBP-encoding domain from five of the meningococcal strains were highly conserved (e.g. > or = 97% homologous). The meningococcal nucleotide sequence was > or = 93% homologous and the consensus meningococcal protein sequence was > or = 97% homologous to FKBP sequences found in seven different commensal Neisseria spp. The meningococcal nucleotide and predicted protein sequences were > or = 59% homologous to the conserved C-terminus of the human FKBP gene family. The FKBP nucleotide sequence was present as a single copy in the chromosome of commensal Neisseria spp. and in most strains of N. meningitidis. The FKBP gene was linked to the silent pilin locus, pilS, in class II-piliated meningococcal strains. In meningococcal strains expressing class I pili, the FKBP gene was linked to one of several pilS loci but not the pilE locus present in these strains. FKBP genes found in commensal Neisseria spp. were not linked to known pilin loci.

Amino Acid Sequence↗
PubMed2000

Phosphorylcholine decoration of lipopolysaccharide differentiates commensal Neisseriae from pathogenic strains: identification of licA-type genes in commensal Neisseriae.

Phosphorylcholine (ChoP) is a potential candidate for a plurispecific vaccine, because it is present on surface components of many mucosal organisms, including Haemophilus influenzae, Streptococcus pneumoniae and Pseudomonas aeruginosa. In addition, ChoP has been detected on pili of Neisseria meningitidis and Neisseria gonorrhoeae. In this study, we demonstrate the presence of the phosphorylcholine epitope on the lipopolysaccharides (LPSs) of several species of commensal Neisseriae (Cn), a property that differentiates commensal from the pathogenic strains of Neisseriae. In an extended survey of 78 strains, we confirmed the exclusive expression of the ChoP epitope on pili of pathogenic Neisseriae. Despite the presence of pili on Cn, which are homologous to Class II pili of N. meningitidis, they did not react with anti-ChoP antibody. This observation was further supported by the fact that 14C-labelled choline was incorporated only in the LPSs of Cn. Analysis of the LPS of N. lactamica strain NL4 revealed two distinct and interconvertible molecular species of LPS with high and low levels of reactivity with anti-ChoP antibody. In addition, on/off phase variation gave rise to frequent modulation in the levels of antibody reactivity. A concurrent modulation was also observed in the binding of C-reactive protein, CRP, a ChoP-binding reactant that is implicated in bacterial clearance. Genetic analysis showed the presence of a gene in several Cn spp. with significant sequence identity to H. influenzae licA. This gene encodes choline kinase and is also involved in phase variation of the LPS-associated ChoP in H. influenzae. In contrast, licA-like genes were not identified in the pathogenic Neisseria strains tested. They are absent from N. meningitidis strain Z2491 genome database. These data suggest that the genetic basis for ChoP incorporation in Cn LPS resembles that in H. influenzae spp. and may be distinct from that generating the ChoP epitope on pili of pathogenic Neisseriae. Further, the modulation of ChoP expression on Cn LPS, and corresponding modulation of CRP binding, has the potential to confer the property of immune avoidance and thus of persistence on mucosa.

Amino Acid Sequence↗
PubMed1986

Increased detection of prolylaminopeptidase in Neisseria meningitidis by Identicult-Neisseria.

Identicult-Neisseria (Scott Laboratories, Inc., Fiskeville, R.I.), a rapid enzymatic method with chromogenic substrates, was tested in our laboratories for the identification of Neisseria gonorrhoea, Neisseria meningitidis, and Neisseria lactamica. The test correlated very highly in its identification of pathogenic Neisseria spp. with modified New York City fermentation medium. Identicult-Neisseria appeared to be more sensitive in its detection of prolylaminopeptidase activity in N. meningitidis than most of the currently available systems.

Aminopeptidases↗