Genetic characterisation of Campylobacter concisus: Strategies for improved genomospecies discrimination.

Although at least two genetically distinct groups, or genomospecies, have been well documented for Campylobacter concisus, no phenotype has yet been identified for their differentiation and thus formal description as separate species. C. concisus has been isolated from a variety of sites in the human body, including saliva and stool samples from both healthy and diarrhoeic individuals.

Complete Genome Sequence of ATCC 33237 and Draft Genome Sequences for an Additional Eight Well-Characterized Strains.

We report the complete genome sequence of the type strain ATCC 33237 and the draft genome sequences of eight additional well-characterized strains. has been shown to be a genetically heterogeneous species, and these nine genomes provide valuable information regarding the diversity within this taxon.

A Designed Experiments Approach to Optimizing MALDI-TOF MS Spectrum Processing Parameters Enhances Detection of Antibiotic Resistance in Campylobacter jejuni.

MALDI-TOF MS has been utilized as a reliable and rapid tool for microbial fingerprinting at the genus and species levels. Recently, there has been keen interest in using MALDI-TOF MS beyond the genus and species levels to rapidly identify antibiotic resistant strains of bacteria. The purpose of this study was to enhance strain level resolution for Campylobacter jejuni through the optimization of spectrum processing parameters using a series of designed experiments.

Multilocus sequence typing methods for the emerging Campylobacter Species C. hyointestinalis, C. lanienae, C. sputorum, C. concisus, and C. curvus.

Multilocus sequence typing (MLST) systems have been reported previously for multiple food- and food animal-associated Campylobacter species (e.g., C.

Molecular Characterization of the 16S rRNA Gene of Helicobacter fennelliae Isolated from Stools and Blood Cultures from Paediatric Patients in South Africa.

Forty strains of H. fennelliae collected from paediatric blood and stool samples over an 18 year period at a children's hospital in Cape Town, South Africa, were amplified by PCR of the 16S rRNA. Two distinct genotypes of H.

An evaluation of the Oxoid Biochemical Identification System Campy rapid screening test for Campylobacteraceae and Helicobacter spp.

Aims: To evaluate the Oxoid Biochemical Identification System (OBIS) Campy test (ID0800M) against Campylobacter; Arcobacter; and other micro-organisms, with similar colonial morphology, for the detection of l-alanine aminopeptidase (l-ALA).

Methods And Results: The KOH and l-ALA (OBIS and Fluka) tests were carried out on every isolate. The procedures were followed as indicated in the OBIS and Fluka kit instructions.

Comparative genomic analysis of clinical strains of Campylobacter jejuni from South Africa.

Background: Campylobacter jejuni is a common cause of acute gastroenteritis and is also associated with the post-infectious neuropathies, Guillain-Barré and Miller Fisher syndromes. In the Cape Town area of South Africa, C. jejuni strains with Penner heat-stable (HS) serotype HS:41 have been observed to be overrepresented among cases of Guillain-Barré syndrome.

Molecular typing, serotyping and cytotoxicity testing of Campylobacter jejuni strains isolated from commercial broilers in Puerto Rico.

Aims: Thirty Campylobacter jejuni strains isolated from fecal samples (n = 94; 32%) from 13 positive farms (n = 17; 76%) from commercial broiler chickens in Puerto Rico were analysed by molecular methods.

Methods And Results: Isolates were identified with multiplex polymerase chain reaction assays, tested for their antimicrobial susceptibility and characterized with pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), serotyping and bacterial cytotoxicity in mammalian cells. Isolates exhibited high resistance to vancomycin (minimum inhibitory concentration, MIC of >256 microg ml(-1)) and trimethoprim (MIC of >32 microg ml(-1)); few were resistant to clindamycin (MIC(90) 4 microg ml(-1)), erythromycin (MIC(90) 8 microg ml(-1)) and tetracycline (MIC(90) 8 microg ml(-1)); but none was resistant to azithromycin (MIC(90) 4 microg ml(-1)), ciprofloxacin (MIC(90) 1 microg ml(-1)) or gentamycin (MIC(90) 4 microg ml(-1)).

Evaluation of different plate media for direct cultivation of Campylobacter species from live broilers.

Accurate identification and optimal culturing procedures for Campylobacter spp. from live broilers are needed for epidemiological studies. Because there is no standardized protocol, we designed and conducted studies to evaluate different selective media for the culturing and isolation of Campylobacter spp.

Common genomic features of Campylobacter jejuni subsp. doylei strains distinguish them from C. jejuni subsp. jejuni.

Background: Campylobacter jejuni has been divided into two subspecies: C. jejuni subsp. jejuni (Cjj) and C.

Identification of genomic differences between Campylobacter jejuni subsp. jejuni and C. jejuni subsp. doylei at the nap locus leads to the development of a C. jejuni subspeciation multiplex PCR method.

Background: The human bacterial pathogen Campylobacter jejuni contains two subspecies: C. jejuni subsp. jejuni (Cjj) and C.

The epidemiology of antibiotic resistance in Campylobacter.

Antibiotic resistance, particularly with the fluoroquinolones and macrolide antibiotics, has now emerged globally with thermophilic campylobacters, including Campylobacter jejuni and C. coli, giving rise to concerns about how these organisms have acquired such resistance characteristics, as well as consequences for human and animal treatment. This review examines (i) the clinical epidemiology of antibiotic resistance in human and animal thermophilic campylobacters, (ii) an update on resistance rates globally, (iii) surveillance of antimicrobial resistance in campylobacters originating from animals, particularly poultry, (iv) the role of the environment in the acquisition and transmission of antibiotic-resistant campylobacters, as well as (v) issues of biocide resistance in campylobacters.

The use of (GTG)5 oligonucleotide as an RAPD primer to type Campylobacter concisus.

Aim: DNA fingerprinting using (GTG)(5) oligonucleotide as a primer in a random amplified polymorphic DNA (RAPD) assay was assessed by typing isolates of Campylobacter concisus strains, collected over a period of 8 years.

Methods And Results: RAPD analysis using the (GTG)(5) oligonucleotide as a primer was used to type 100 isolates of C. concisus comprising mostly isolates from children with diarrhoea.

Identification of DNA sequence variation in Campylobacter jejuni strains associated with the Guillain-Barré syndrome by high-throughput AFLP analysis.

Background: Campylobacter jejuni is the predominant cause of antecedent infection in post-infectious neuropathies such as the Guillain-Barré (GBS) and Miller Fisher syndromes (MFS). GBS and MFS are probably induced by molecular mimicry between human gangliosides and bacterial lipo-oligosaccharides (LOS). This study describes a new C.

Absence of Helicobacter pylori within the oral cavities of members of a healthy South African community.

Our study aimed to evaluate the oral cavity as a reservoir from where Helicobacter pylori may be transmitted. Histology and PCR amplification were performed. Eighty-four percent of the stomach biopsies tested positive; however, H.

Extended multilocus sequence typing system for Campylobacter coli, C. lari, C. upsaliensis, and C. helveticus.

A multilocus sequence typing (MLST) system has been reported previously for Campylobacter jejuni to both differentiate strains and identify clonal lineages. However, sequence variation at the MLST loci prevents its use for closely related Campylobacter species. We describe herein an expanded MLST method to include three clinically relevant Campylobacter species, C.

Genetic basis of quinolone resistance and epidemiology of resistant and susceptible isolates of porcine Campylobacter coli strains.

Aims: The aims of this study were to investigate the epidemiology of quinolone-resistant and -susceptible porcine isolates of Campylobacter coli and to characterize the genetic basis of quinolone resistance.

Methods And Results: Penner serotyping and flagellin gene sequence polymorphisms were used to investigate the epidemiology of the C. coli isolates.

Genetic heterogeneity of Campylobacter concisus determined by pulsed field gel electrophoresis-based macrorestriction profiling.

In order to investigate the genetic diversity of Campylobacter concisus to assist molecular typing studies, the use of macrorestriction profiling was examined. A suitable protocol was developed that included the use of formaldehyde pretreatment to prevent DNA degradation, and restriction enzyme NotI for pulsed field gel electrophoresis-based genotyping. Subsequently, 53 strains of C.

The pepsinogen releasing effect of Helicobacter pylori lipopolysaccharide.

Background: Helicobacter pylori lipopolysaccharide (LPS) affects pepsinogen release by a nontoxic mechanism. We hypothesized that this effect was characteristic of the organism and related to the clinical status of the strain.

Materials And Methods: LPS was isolated from 11 H.

Evaluation of a novel heminested PCR assay based on the phosphoglucosamine mutase gene for detection of Helicobacter pylori in saliva and dental plaque.

A novel heminested PCR protocol was developed for the specific detection of Helicobacter pylori at low copy numbers. A set of primers specific for the phosphoglucosamine mutase gene (glmM) of H. pylori produced a 765-bp fragment that was used as template for the heminested primer pair delineating a 496-bp fragment.