Campylobacter lari
Campylobacter
Campylobacter jejuni
Campylobacter coli
Campylobacter fetus
Bacterial Typing Techniques
Toward an international standard for PCR-based detection of food-borne thermotolerant Campylobacters: assay development and analytical validation. (1/14)
As part of a European research project (FOOD-PCR), we developed a standardized and robust PCR detection assay specific for the three most frequently reported food-borne pathogenic Campylobacter species, C. jejuni, C. coli, and C. lari. Fifteen published and unpublished PCR primers targeting the 16S rRNA gene were tested in all possible pairwise combinations, as well as two published primers targeting the 23S rRNA gene. A panel of 150 strains including target and nontarget strains was used in an in-house validation. Only one primer pair, OT1559 plus 18-1, was found to be selective. The inclusivity and exclusivity were 100 and 97%, respectively. In an attempt to find a thermostable DNA polymerase more resistant than Taq to PCR inhibitors present in chicken samples, three DNA polymerases were evaluated. The DNA polymerase Tth was not inhibited at a concentration of 2% (vol/vol) chicken carcass rinse, unlike both Taq DNA polymerase and DyNAzyme. Based on these results, Tth was selected as the most suitable enzyme for the assay. The standardized PCR test described shows potential for use in large-scale screening programs for food-borne Campylobacter species under the assay conditions specified. (+info)Toward an international standard for PCR-based detection of food-borne thermotolerant Campylobacters: validation in a multicenter collaborative trial. (2/14)
As part of a European research project, the performance of a PCR assay to detect food-borne thermotolerant campylobacters (Campylobacter jejuni, C. coli, and C. lari) was evaluated through an international collaborative trial involving 12 participating laboratories. DNA from 10 target and 8 nontarget strains was tested, and the results were reported as the presence of a positive signal after gel electrophoresis. The overall inclusivity (sensitivity) was 93.7%, and the exclusivity (specificity) was 100%. The results indicate that the assay can become an international standard and can be confidently applied in microbiological laboratories. (+info)Identification of distinct Campylobacter lari genogroups by amplified fragment length polymorphism and protein electrophoretic profiles. (3/14)
Campylobacter lari is a phenotypically and genotypically diverse species that comprises the classical nalidixic acid-resistant thermophilic campylobacters (NARTC) and the biochemical C. lari variants, including the urease-positive campylobacters (UPTC), the nalidixic acid-susceptible campylobacters (NASC), and the urease-producing nalidixic acid-susceptible campylobacters. To study the taxonomic and epidemiological relationships among strains of the C. lari variants, amplified fragment length polymorphism (AFLP) profiling and whole-cell protein profile analysis were performed with 55 C. lari strains. Great genetic heterogeneity in AFLP and protein profiles was observed. Numerical analysis of AFLP profiles and of partial protein profiles allowed discrimination of four distinct genogroups. AFLP cluster I included nearly homogeneous patterns for C. lari NARTC strains (genogroup I). UPTC strains together with non-urease-producing NASC strains produced highly diverse patterns and were placed in genogroup II. The genogroup III strains had the NASC phenotype and produced more homogeneous patterns. Finally, genogroup IV strains had the classical NARTC phenotype and produced AFLP patterns that were very distinct from those of other genogroups. One UPTC strain had aberrant patterns and clustered separately, which may indicate that there is an additional genogroup. Preliminary DNA-DNA hybridization experiments suggested that genogroups I and III represent a single genomic species and that genogroup IV represents a distinct species. The detection of moderate levels of DNA-DNA hybridization between a genogroup II reference strain and genogroup I and III reference strains highlights the need for further DNA-DNA hybridization experiments to clarify the taxonomic status of the former group. No correlation of genogroups with different sources of strains was identified. These data show that UPTC strains are genetically diverse and distinct from NARTC strains. In addition, they indicate that the classical NARTC phenotype encompasses at least two genogroups. (+info)Use of the omp50 gene for identification of Campylobacter species by PCR. (4/14)
We studied the prevalence of the omp50 gene and the Omp50 protein in Campylobacter strains. Immunodetection assays and DNA-DNA hybridizations showed that most C. coli strains tested were negative and most C. jejuni and C. lari strains tested were positive. A PCR assay was developed, using the omp50 gene as a species-specific target. We propose a combination of a hippurate test and an omp50 assay to perform identification of Campylobacter species. (+info)Differentiation of Campylobacter coli, Campylobacter jejuni, Campylobacter lari, and Campylobacter upsaliensis by a multiplex PCR developed from the nucleotide sequence of the lipid A gene lpxA. (5/14)
We describe a multiplex PCR assay to identify and discriminate between isolates of Campylobacter coli, Campylobacter jejuni, Campylobacter lari, and Campylobacter upsaliensis. The C. jejuni isolate F38011 lpxA gene, encoding a UDP-N-acetylglucosamine acyltransferase, was identified by sequence analysis of an expression plasmid that restored wild-type lipopolysaccharide levels in Escherichia coli strain SM105 [lpxA(Ts)]. With oligonucleotide primers developed to the C. jejuni lpxA gene, nearly full-length lpxA amplicons were amplified from an additional 11 isolates of C. jejuni, 20 isolates of C. coli, 16 isolates of C. lari, and five isolates of C. upsaliensis. The nucleotide sequence of each amplicon was determined, and sequence alignment revealed a high level of species discrimination. Oligonucleotide primers were constructed to exploit species differences, and a multiplex PCR assay was developed to positively identify isolates of C. coli, C. jejuni, C. lari, and C. upsaliensis. We characterized an additional set of 41 thermotolerant isolates by partial nucleotide sequence analysis to further demonstrate the uniqueness of each species-specific region. The multiplex PCR assay was validated with 105 genetically defined isolates of C. coli, C. jejuni, C. lari, and C. upsaliensis, 34 strains representing 12 additional Campylobacter species, and 24 strains representing 19 non-Campylobacter species. Application of the multiplex PCR method to whole-cell lysates obtained from 108 clinical and environmental thermotolerant Campylobacter isolates resulted in 100% correlation with biochemical typing methods. (+info)Extended multilocus sequence typing system for Campylobacter coli, C. lari, C. upsaliensis, and C. helveticus. (6/14)
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. coli, C. lari, and C. upsaliensis, and a fourth Campylobacter species, C. helveticus. The C. coli and C. helveticus methods use the same seven C. jejuni loci (aspA, atpA, glnA, gltA, glyA, pgm, and tkt); however, adk and pgi were substituted for aspA and gltA in C. lari and for gltA and pgm in C. upsaliensis. Multiple C. coli (n = 57), C. lari (n = 20), C. upsaliensis (n = 78), and C. helveticus (n = 9) isolates, representing both clinical and environmental sources, were typed. All four species were genetically diverse: the majority (> 80%) of the isolates had unique sequence types (STs). Using this method, mixed C. lari, C. upsaliensis, and C. helveticus isolates were identified; upon separation, each isolate was shown to contain two strains of the same species with distinct STs. Additionally, the expanded MLST method was able to detect potential lateral transfer events between C. jejuni and either C. coli or C. lari and between C. upsaliensis and C. helveticus. Thus, the expanded MLST method will prove useful in differentiating strains of five Campylobacter species, identifying mixed Campylobacter cultures, and detecting genetic exchange within the genus. (+info)Speciation of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis by matrix-assisted laser desorption ionization-time of flight mass spectrometry. (7/14)
Multiple strains of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis isolated from animal, clinical, or food samples have been analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Whole bacterial cells were harvested from colonies or confluent growth on agar and transferred directly into solvent and then to a spot of dried 3-methoxy-4-hydroxycinnamic acid (matrix). Multiple ions in the 5,000- to 15,000-Da mass range were evident in spectra for each strain; one or two ions in the 9,500- to 11,000-Da range were consistently high intensity. "Species-identifying" biomarker ions (SIBIs) were evident from analyses of multiple reference strains for each of the six species, including the genome strains C. jejuni NCTC 11168 and C. jejuni RM1221. Strains grown on nine different combinations of media and atmospheres yielded SIBI masses within +/-5 Da with external instrument calibration. The highest-intensity C. jejuni SIBIs were cytosolic proteins, including GroES, HU/HCj, and RplL. Multiple intraspecies SIBIs, corresponding probably to nonsynonymous nucleotide polymorphisms, also provided some intraspecies strain differentiation. MALDI-TOF MS analysis of 75 additional Campylobacter strains isolated from humans, poultry, swine, dogs, and cats revealed (i) associations of SIBI type with source, (ii) strains previously speciated incorrectly, and (iii) "strains" composed of more than one species. MALDI-TOF MS provides an accurate, sensitive, and rapid method for identification of multiple Campylobacter species relevant to public health and food safety. (+info)Recurrent Campylobacter lari bacteremia in X-linked agammaglobulinemia: a case report and review. (8/14)
X-linked agammaglobulinemia (XLA) is a primary immune deficiency disease with a B-cell defect. We present the first XLA patient who had recurrent Campylobacter lari bacteremia. High dose intravenous immunoglobulin combined with azithromycin once per week, and a complete avoidance of bacterial reservoirs may be helpful for the prevention of C. lari bacteremia. (+info)Campylobacter lari is a species of bacteria that can cause gastrointestinal illness in humans. It is one of several species within the genus Campylobacter, which are known to be significant causes of foodborne illness worldwide. C. lari is commonly found in the intestines of birds and other animals, and human infection typically occurs through the consumption of contaminated food or water.
The symptoms of a C. lari infection can include diarrhea, abdominal cramps, fever, and vomiting. The illness is usually self-limiting and resolves within a few days to a week, although in some cases it may lead to more severe complications such as bacteremia (bacteria in the bloodstream) or Guillain-Barré syndrome, a serious neurological condition.
Prevention measures include proper food handling and cooking techniques, as well as good hygiene practices such as handwashing after using the bathroom and before preparing or eating food. If you suspect that you have a C. lari infection, it is important to seek medical attention promptly to receive appropriate treatment and prevent complications.
'Campylobacter' is a genus of gram-negative, spiral-shaped bacteria that are commonly found in the intestinal tracts of animals, including birds and mammals. These bacteria are a leading cause of bacterial foodborne illness worldwide, with Campylobacter jejuni being the most frequently identified species associated with human infection.
Campylobacter infection, also known as campylobacteriosis, typically causes symptoms such as diarrhea (often bloody), abdominal cramps, fever, and vomiting. The infection is usually acquired through the consumption of contaminated food or water, particularly undercooked poultry, raw milk, and contaminated produce. It can also be transmitted through contact with infected animals or their feces.
While most cases of campylobacteriosis are self-limiting and resolve within a week without specific treatment, severe or prolonged infections may require antibiotic therapy. In rare cases, Campylobacter infection can lead to serious complications such as bacteremia (bacterial bloodstream infection), meningitis, or Guillain-Barré syndrome, a neurological disorder that can cause muscle weakness and paralysis.
Preventive measures include proper food handling and cooking techniques, thorough handwashing, and avoiding cross-contamination between raw and cooked foods.
'Campylobacter jejuni' is a gram-negative, spiral-shaped bacterium that is a common cause of foodborne illness worldwide. It is often found in the intestines of warm-blooded animals, including birds and mammals, and can be transmitted to humans through contaminated food or water.
The bacteria are capable of causing an infection known as campylobacteriosis, which is characterized by symptoms such as diarrhea, abdominal cramps, fever, and vomiting. In severe cases, the infection can spread to the bloodstream and cause serious complications, particularly in individuals with weakened immune systems.
'Campylobacter jejuni' is one of the most common causes of foodborne illness in the United States, with an estimated 1.3 million cases occurring each year. It is often found in undercooked poultry and raw or unpasteurized milk products, as well as in contaminated water supplies. Proper cooking and pasteurization can help reduce the risk of infection, as can good hygiene practices such as washing hands thoroughly after handling raw meat and vegetables.
Campylobacter infections are illnesses caused by the bacterium *Campylobacter jejuni* or other species of the genus *Campylobacter*. These bacteria are commonly found in the intestines of animals, particularly birds, and can be transmitted to humans through contaminated food, water, or contact with infected animals.
The most common symptom of Campylobacter infection is diarrhea, which can range from mild to severe and may be bloody. Other symptoms may include abdominal cramps, fever, nausea, and vomiting. The illness usually lasts about a week, but in some cases, it can lead to serious complications such as bacteremia (bacteria in the bloodstream), meningitis, or Guillain-Barré syndrome, a neurological disorder that can cause muscle weakness and paralysis.
Campylobacter infections are typically treated with antibiotics, but in mild cases, they may resolve on their own without treatment. Prevention measures include cooking meat thoroughly, washing hands and surfaces that come into contact with raw meat, avoiding unpasteurized dairy products and untreated water, and handling pets, particularly birds and reptiles, with care.
'Campylobacter coli' is a species of bacteria that can cause gastrointestinal illness in humans. It is one of the several species within the genus Campylobacter, which are gram-negative, microaerophilic, spiral or curved rods. 'Campylobacter coli' is commonly found in the intestines of animals, particularly swine and cattle, and can be transmitted to humans through contaminated food or water.
The most common symptom of infection with 'Campylobacter coli' is diarrhea, which can range from mild to severe and may be accompanied by abdominal cramps, fever, nausea, and vomiting. The illness, known as campylobacteriosis, typically lasts for about a week and resolves on its own without specific treatment in most cases. However, in some cases, the infection can lead to more serious complications, such as bacteremia (bacterial infection of the blood) or Guillain-Barré syndrome, a rare neurological disorder that can cause muscle weakness and paralysis.
Prevention measures include cooking food thoroughly, washing hands and surfaces frequently, and avoiding cross-contamination between raw and cooked foods. 'Campylobacter coli' infections are also reportable to public health authorities in many jurisdictions, as they are considered a significant cause of foodborne illness worldwide.
'Campylobacter fetus' is a species of gram-negative, microaerophilic bacteria that can cause gastrointestinal infections in humans. It is commonly found in the intestinal tracts of animals, particularly cattle, and can be transmitted to humans through contaminated food or water.
The infection caused by 'Campylobacter fetus' is known as campylobacteriosis, which typically presents with symptoms such as diarrhea, abdominal cramps, fever, and vomiting. In some cases, the infection can also lead to serious complications such as bacteremia (bacterial infection of the blood) and Guillain-Barré syndrome, a neurological disorder that can cause muscle weakness and paralysis.
It's important to note that while 'Campylobacter fetus' is a significant cause of foodborne illness, it can be prevented through proper food handling and preparation practices, such as cooking meats thoroughly and avoiding cross-contamination between raw and cooked foods.
Bacterial typing techniques are methods used to identify and differentiate bacterial strains or isolates based on their unique characteristics. These techniques are essential in epidemiological studies, infection control, and research to understand the transmission dynamics, virulence, and antibiotic resistance patterns of bacterial pathogens.
There are various bacterial typing techniques available, including:
1. **Bacteriophage Typing:** This method involves using bacteriophages (viruses that infect bacteria) to identify specific bacterial strains based on their susceptibility or resistance to particular phages.
2. **Serotyping:** It is a technique that differentiates bacterial strains based on the antigenic properties of their cell surface components, such as capsules, flagella, and somatic (O) and flagellar (H) antigens.
3. **Biochemical Testing:** This method uses biochemical reactions to identify specific metabolic pathways or enzymes present in bacterial strains, which can be used for differentiation. Commonly used tests include the catalase test, oxidase test, and various sugar fermentation tests.
4. **Molecular Typing Techniques:** These methods use genetic markers to identify and differentiate bacterial strains at the DNA level. Examples of molecular typing techniques include:
* **Pulsed-Field Gel Electrophoresis (PFGE):** This method uses restriction enzymes to digest bacterial DNA, followed by electrophoresis in an agarose gel under pulsed electrical fields. The resulting banding patterns are analyzed and compared to identify related strains.
* **Multilocus Sequence Typing (MLST):** It involves sequencing specific housekeeping genes to generate unique sequence types that can be used for strain identification and phylogenetic analysis.
* **Whole Genome Sequencing (WGS):** This method sequences the entire genome of a bacterial strain, providing the most detailed information on genetic variation and relatedness between strains. WGS data can be analyzed using various bioinformatics tools to identify single nucleotide polymorphisms (SNPs), gene deletions or insertions, and other genetic changes that can be used for strain differentiation.
These molecular typing techniques provide higher resolution than traditional methods, allowing for more accurate identification and comparison of bacterial strains. They are particularly useful in epidemiological investigations to track the spread of pathogens and identify outbreaks.
Bacterial DNA refers to the genetic material found in bacteria. It is composed of a double-stranded helix containing four nucleotide bases - adenine (A), thymine (T), guanine (G), and cytosine (C) - that are linked together by phosphodiester bonds. The sequence of these bases in the DNA molecule carries the genetic information necessary for the growth, development, and reproduction of bacteria.
Bacterial DNA is circular in most bacterial species, although some have linear chromosomes. In addition to the main chromosome, many bacteria also contain small circular pieces of DNA called plasmids that can carry additional genes and provide resistance to antibiotics or other environmental stressors.
Unlike eukaryotic cells, which have their DNA enclosed within a nucleus, bacterial DNA is present in the cytoplasm of the cell, where it is in direct contact with the cell's metabolic machinery. This allows for rapid gene expression and regulation in response to changing environmental conditions.