High Nutrient Concentration Can Induce Virulence Factor Expression and Cause Higher Virulence in an Environmentally Transmitted Pathogen

Higher resource level promotes virulence in an environmentally transmitted bacterial fish pathogen

Diseases have become a primary constraint to sustainable aquaculture, but remarkably little attention has been paid to a broad class of pathogens: the opportunists. Opportunists often persist in the environment outside the host, and their pathogenic features are influenced by changes in the environment. To test how environmental nutrient levels influence virulence, we used strains of Flavobacte...

Bacteria Pathogen Virulence Primer

Relationship of virulence factor expression to evolved virulence in mouse-passaged Cryptococcus neoformans lines.

Serial passage of Cryptococcus neoformans in mice increases virulence relative to the nonpassaged line. Postpassaged lines showed no difference in the expression of most known virulence factors, with the exception that the more virulent lines had smaller capsules in vitro. These data imply that other mechanisms of virulence remain to be discovered.

Organelles as virulence factors of an opportunistic pathogen Pseudomonas aeruginosa

Type IV pili (T4P) and flagellum are well known virulence factors of an opportunistic pathogen Pseudomonas aeruginosa. T4P pili provide twitching motility, adherence to biotic/abiotic surfaces, intercellular association that is essential to biophilm formation, and are implicated in chemotaxis, bacteriophage adsorption and DNA uptake. Flagellum provides swimming/swarming motilities and chemotaxi...

Manipulating virulence factor availability can have complex consequences for infections

Given the rise of bacterial resistance against antibiotics, we urgently need alternative strategies to fight infections. Some propose we should disarm rather than kill bacteria, through targeted disruption of their virulence factors. It is assumed that this approach (i) induces weak selection for resistance because it should only minimally impact bacterial fitness, and (ii) is specific, only in...