Background: Lactococcus garvieae causes lactococcosis in rainbow trout in many parts of the world. Aims: This study was conducted for the existence of the virulent factors and differentiation of the two serotypes in L. garvieae. Methods: Twenty-two strains of L. garvieae isolated from diseased rainbow trout from farms...

Alternaria brown spot disease is caused by the alternata tangerine pathotype, which relies on ACT-toxin for infection. At present, all identified biosynthesis-related genes are multi-copy genes. In this study, we summarized advances in important host-specific toxins (HSTs), and listed key required pathogenicity of A. pathotype. Toxin virulence test results revealed that different citrus species...

Background: Escherichia coli (E. coli) remains one of the leading agents of urinary tract infection (UTIs), it has become resistant to many drugs. Current work aimed to evaluate some chemical substances as antibacterial agents and molecular study of virulence factors associated with UTIs. Methods: This work involved 133 urine specimens obtained from females’ patients suffering from UTIs, Met...

Potential virulence, as defined by combined levels of adhesion to urinary epithelial cells, serum resistance, and mouse toxicity, was assessed for Escherichia coli strains causing symptomatic and asymptomatic urinary tract infections in relation to the carriage of hemolysin and other suspected virulence determinants. Hemolysin production (Hly), associated with certain O (O4, O6, O18, and O75), ...

RNA viruses exist as genetically diverse populations displaying a range of virulence degrees. The evolution of virulence in viral populations is, however, poorly understood. On the basis of the experimental observation of an RNA virus clone in cell culture diversifying into two subpopulations of different virulence, we study the dynamics of mutating virus populations with varying virulence. We ...

In this study, we examined the virulence factors and pathogenesis of Vibrio parahaemolyticus in Epinephelus awoara. The chemotactic motility of V. parahaemolyticus for phagocytosis and intracellular survival in fish macrophages was determined using virulence strains and low-virulence strains of V. parahaemolyticus. We found that the intracellular mean number of virulence strains of V. parahaemo...

Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5-10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work, we studied the virulence of aeromonads recovered from human mixed infections. We tested them indi...

Previous studies suggesting a link between Escherichia coli phylogenetic groups and extraintestinal virulence have been hampered by the difficulty in establishing the intrinsic virulence of a bacterial strain. Indeed, unidentified virulence factors do exist, and the susceptibility of the host to infection is highly variable. To overcome these difficulties, we have developed a mouse model of ext...

Salmonella is one of the most important zoonotic pathogens with many virulence factors playing a major role in its pathogenesis. The aims of this study were to detect spvA, int2 and invC virulence genes of different Salmonella serotypes isolated from various clinical animal and human sources, and to investigate antibiotic resistance patterns among these serotypes. Using a PCR assay, a total of ...