Project description:We report here the complete genome analysis of a clinical <i>Campylobacter jejuni</i> strain sequenced by a hybrid assembly approach. A hybrid assembly approach provided a complete genome sequence of <i>C. jejuni</i> that contains a 1,681,375-bp chromosome and 47,467-bp plasmid carrying various virulence and antimicrobial resistance determinants.
Project description:Campylobacter jejuni subsp. jejuni and Campylobacter coli are leading causes of gastroenteritis, with virulence linked to cell surface carbohydrate diversity. Although the associated gene clusters are well studied for C. jejuni subsp. jejuni, C. coli has been largely neglected. Here we provide comparative analysis of the lipooligosaccharide (LOS) and capsular polysaccharide (CPS) gene clusters, using genome and cluster sequence data for 36 C. coli strains, 67 C. jejuni subsp. jejuni strains and ten additional Campylobacter species. Similar to C. jejuni subsp. jejuni, C. coli showed high LOS/CPS gene diversity, with each cluster delineated into eight gene content classes. This diversity was predominantly due to extensive gene gain/loss, with the lateral transfer of genes likely occurring both within and between species and also between the LOS and CPS. Additional mechanisms responsible for LOS/CPS diversity included phase-variable homopolymeric repeats, gene duplication/inactivation, and possibly host environment selection pressure. Analyses also showed that (i) strains of C. coli and Campylobacter upsaliensis possessed genes homologous to the sialic acid genes implicated in the neurological disorder Guillain-Barré syndrome (GBS), and (ii) C. coli LOS classes were differentiated between bovine and poultry hosts, potentially aiding post infection source tracking.
Project description:Campylobacter species are a leading cause of bacterial foodborne illness worldwide. Despite the global efforts to curb them, Campylobacter infections have increased continuously in both developed and developing countries. The development of effective strategies to control the infection by this pathogen is warranted. The essential genes of bacteria are the most prominent targets for this purpose. In this study, we used transposon sequencing (Tn-seq) of a genome-saturating library of Tn5 insertion mutants to define the essential genome of C. jejuni at a high resolution.We constructed a Tn5 mutant library of unprecedented complexity in C. jejuni NCTC 11168 with 95,929 unique insertions throughout the genome and used the genomic DNA of the library for the reconstruction of Tn5 libraries in the same (C. jejuni NCTC 11168) and different strain background (C. jejuni 81-176) through natural transformation. We identified 166 essential protein-coding genes and 20 essential transfer RNAs (tRNA) in C. jejuni NCTC 11168 which were intolerant to Tn5 insertions during in vitro growth. The reconstructed C. jejuni 81-176 library had 384 protein coding genes with no Tn5 insertions. Essential genes in both strain backgrounds were highly enriched in the cluster of orthologous group (COG) categories of 'Translation, ribosomal structure and biogenesis (J)', 'Energy production and conversion (C)', and 'Coenzyme transport and metabolism (H)'.Comparative analysis among this and previous studies identified 50 core essential genes of C. jejuni, which can be further investigated for the development of novel strategies to control the spread of this notorious foodborne bacterial pathogen.
Project description:<i>Campylobacter jejuni</i> is among the most prevalent foodborne zoonotic pathogens leading to diarrheal diseases. In this study, we developed a CRISPR-Cas12b-based system to rapidly and accurately detect <i>C. jejuni</i> contamination. Identification of <i>C. jejuni</i>-specific and -conserved genomic signatures is a fundamental step in development of the detection system. By comparing <i>C. jejuni</i> genome sequences with those of the closely related <i>Campylobacter coli</i>, followed by comprehensive online BLAST searches, a 20-bp <i>C. jejuni</i>-conserved (identical in 1024 out of 1037 analyzed <i>C. jejuni</i> genome sequences) and -specific (no identical sequence detected in non-<i>C. jejuni</i> strains) sequence was identified and the system was then assembled. In further experiments, strong green fluorescence was observed only when <i>C. jejuni</i> DNA was present in the system, highlighting the specificity of this system. The assay, with a sample-to-answer time of ∼40 min, positively detected chicken samples that were contaminated with a dose of approximately 10 CFU <i>C. jejuni</i> per gram of chicken, which was >10 times more sensitive than the traditional <i>Campylobacter</i> isolation method, suggesting that this method shows promise for onsite <i>C. jejuni</i> detection. This study provides an example of bioinformatics-guided CRISPR-Cas12b-based detection system development for rapid and accurate onsite pathogen detection.
Project description:We report the use of differential RNA-sequencing for the determination of the primary transcriptome of the fur perR mutant of Campylobacter jejuni NCTC 11168. This allows for the genome-wide determination of transcription start sites. Campylobacter jejuni NCTC 11168 fur perR mutant was grown to late log phase, RNA was purified and used for differential RNA-sequencing by 454 sequencing with barcoded libraries, and used for determination of genome-wide transcription start sites
Project description:Campylobacter jejuni subsp. jejuni infections are a leading cause of foodborne gastroenteritis and the most prevalent antecedent to Guillain-Barré syndrome (GBS). Penner serotype HS:19 is among several capsular types shown to be markers for GBS. This study describes the genome of C. jejuni subsp. jejuni HS:19 Penner reference strain RM3420.
Project description:Here, we report the complete genome sequence of Campylobacter jejuni ATCC 35925, an avian isolate from Sweden. The genome gives insight into the ATCC 35925 strain's remarkable ability to tolerate copper and its permissiveness to plasmid transformation.
Project description:Genome sequences of Campylobacter jejuni FJ3124 and ZP3204 isolated from retail chicken gizzards and Campylobacter jejuni TS1218 isolated from retail chicken showed the presence of 1,694,324-, 1,763,161-, and 1,762,596-bp circular chromosomes, respectively. Campylobacter jejuni ZP3204 and TS1218 harbored large tetracycline resistance plasmids with type IV secretion systems.
Project description:Campylobacter jejuni strain M1 (laboratory designation 99/308) is a rarely documented case of direct transmission of C. jejuni from chicken to a person, resulting in enteritis. We have sequenced the genome of C. jejuni strain M1, and compared this to 12 other C. jejuni sequenced genomes currently publicly available. Compared to these, M1 is closest to strain 81116. Based on the 13 genome sequences, we have identified the C. jejuni pan-genome, as well as the core genome, the auxiliary genes, and genes unique between strains M1 and 81116. The pan-genome contains 2,427 gene families, whilst the core genome comprised 1,295 gene families, or about two-thirds of the gene content of the average of the sequenced C. jejuni genomes. Various comparison and visualization tools were applied to the 13 C. jejuni genome sequences, including a species pan- and core genome plot, a BLAST Matrix and a BLAST Atlas. Trees based on 16S rRNA sequences and on the total gene families in each genome are presented. The findings are discussed in the background of the proven virulence potential of M1.
Project description:Campylobacter jejuni is an enteric bacterium that can cause abortion in livestock. This is the release of a multidrug-resistant Campylobacter jejuni genome from an isolate that caused an abortion in a cow in northern California. This isolate is part of the 100K Pathogen Genome Project.