The association between Escherichia coli virulence factors and chronic intestinal disorders is mostly unknown. The presented study compared the distribution of virulence genes and phylogroups among E. coli isolated from chronic intestinal disorders such as Crohn's disease and irritable bowel syndrome (IBS) with strains isolated from patients with acute diarrhea as a control group. The presence ...

The complete nucleotide sequence of pKDSC50, a large virulence plasmid from Salmonella enterica serovar Choleraesuis strain RF-1, has been determined. We identified 48 of the open reading frames (ORFs) encoded by the 49,503-bp molecule. pKDSC50 encodes a known virulence-associated operon, the spv operon, which is composed of genes essential for systemic infection by nontyphoidal Salmonella. Ana...

The phylogenetic profile of a gene is a reflection of its evolutionary history and can be defined as the differential presence or absence of a gene in a set of reference genomes. It has been employed to facilitate the prediction of gene functions. However, the hypothesis that the application of this concept can also facilitate the discovery of bacterial virulence factors has not been fully exam...

The costs and benefits of parasite virulence are analysed in an evolutionarily stable strategy (ESS) model. Increased host mortality caused by disease (virulence) reduces a parasite's fitness by damaging its food supply. The fitness costs of high virulence may be offset by the benefits of increased transmission or ability to withstand the host's defences. It has been suggested that multiple inf...

Pseudomonas aeruginosa is an opportunistic pathogen that is capable of causing both acute and chronic infections. P. aeruginosa virulence is subject to sophisticated regulatory control by two-component systems that enable it to sense and respond to environmental stimuli. We recently reported that the two-component sensor KinB regulates virulence in acute P. aeruginosa infection. Furthermore, it...

1. Smooth colony pneumococci fresh from human beings, instilled in small doses into the nasal passages of special mice raised under standard conditions, brought about a characteristic infection and this spread to healthy contacts inciting in them the carrier state or fatal infection. 2. Differences in individual host response to the same dose of a given culture ranged from a complete refractory...