Conservation of σ28-Dependent Non-Coding RNA Paralogs and Predicted σ54-Dependent Targets in Thermophilic Campylobacter Species.

Assembly of flagella requires strict hierarchical and temporal control via flagellar sigma and anti-sigma factors, regulatory proteins and the assembly complex itself, but to date non-coding RNAs (ncRNAs) have not been described to regulate genes directly involved in flagellar assembly. In this study we have investigated the possible role of two ncRNA paralogs (CjNC1, CjNC4) in flagellar assembly and gene regulation of the diarrhoeal pathogen Campylobacter jejuni. CjNC1 and CjNC4 are 37/44 nt identical and predicted to target the 5' untranslated region (5' UTR) of genes transcribed from the flagellar sigma factor σ54.

A proposed essential gene discovery pipeline: a Campylobacter jejuni case study.

Genes required for an organism's growth and survival are termed essential and represent potential intervention targets. Following in the footsteps of the genomics era, the "next-gen" genomic era provides vast amounts of genetic information. Sequencing of a representative bacterial pathogen genome has been superseded by sequencing of whole strain collections, whether from environmental or clinical sources (Harris et al.

Functional characterisation of germinant receptors in Clostridium botulinum and Clostridium sporogenes presents novel insights into spore germination systems.

Clostridium botulinum is a dangerous pathogen that forms the highly potent botulinum toxin, which when ingested causes a deadly neuroparalytic disease. The closely related Clostridium sporogenes is occasionally pathogenic, frequently associated with food spoilage and regarded as the non-toxigenic equivalent of Group I C. botulinum.

In vivo and in silico determination of essential genes of Campylobacter jejuni.

Background: In the United Kingdom, the thermophilic Campylobacter species C. jejuni and C. coli are the most frequent causes of food-borne gastroenteritis in humans.

Alternative spermidine biosynthetic route is critical for growth of Campylobacter jejuni and is the dominant polyamine pathway in human gut microbiota.

The availability of fully sequenced bacterial genomes has revealed that many species known to synthesize the polyamine spermidine lack the spermidine biosynthetic enzymes S-adenosylmethionine decarboxylase and spermidine synthase. We found that such species possess orthologues of the sym-norspermidine biosynthetic enzymes carboxynorspermidine dehydrogenase and carboxynorspermidine decarboxylase. By deleting these genes in the food-borne pathogen Campylobacter jejuni, we found that the carboxynorspermidine decarboxylase orthologue is responsible for synthesizing spermidine and not sym-norspermidine in vivo.

Random mutagenesis strategies for Campylobacter and Helicobacter species.

Campylobacter and Helicobacter species are important pathogens in man and animals. The study of their virulence and physiology has been difficult due to the lack of tractable genetic tools, since many of the techniques established in Escherichia coli and related species were found to be non-functional in Campylobacter and Helicobacter species. The advent of functional genomics techniques in the last decade has been accompanied by the development of genetic tools, which take advantage of specific features of Campylobacter and Helicobacter, like natural transformation.

Riboflavin biosynthesis is associated with assimilatory ferric reduction and iron acquisition by Campylobacter jejuni.

One of the pathways involved in the acquisition of the essential metal iron by bacteria involves the reduction of insoluble Fe(3+) to soluble Fe(2+), followed by transport of Fe(2+) to the cytoplasm. Flavins have been implicated as electron donors in this poorly understood process. Ferrous iron uptake is essential for intestinal colonization by the important pathogen Campylobacter jejuni and may be of particular importance under low-oxygen conditions.

The complete genome sequence of Campylobacter jejuni strain 81116 (NCTC11828).

Campylobacter jejuni is a major human enteric pathogen that displays genetic variability via genomic reorganization and phase variation. This variability can adversely affect the outcomes and reproducibility of experiments. C.