Sentence examples for decrease in virulence from inspiring English sources
In order to understand the mechanisms underlying the differences observed in mouse survival, the most virulent isolate (124A) and the isolate with the most significant decrease in virulence (140A) were further studied.
Intriguingly, the pqsH mutant did not result in a decrease in virulence in burn-wound mouse model (Xiao et al., 2006b), but displayed a reduced killing on nematodes (Gallagher et al., 2002), hence the importance of PQS in regulation of virulence remains debatable.
What is most interesting in Smith et al.'s (2006) study from the trait loss perspective is the observed decrease in virulence factors (loss of serotype-specific antigenicity, loss of secreted protease activity, reduced biofilm production) in the 96-month isolate.
Interestingly, these isolates showed a clear progressive decrease in virulence in an i.v. mouse model of systemic infection.
Moreover, replacement of the PB2 or PB1 proteins led to decreased replication in tissues and, consequently, a decrease in virulence [48].
In S. Typhi and S. Typhimurium, PhoP/Q is required for intra-macrophage survival, and mutations in phoP/Q result in a marked decrease in virulence [5] [7].
Despite the lack of involvement of Isd/Hts during the pathogenesis of pneumonia, these studies establish that S. aureus strains unable to acquire iron through either the Hts or Isd systems are severely decreased in virulence in a systemic model of infection.
Some fungal lineages increased and others decreased in virulence.
Even in bacteria-bacteriophage systems where transmissive stages have been included, decreases in virulence over evolutionary time have been recorded.
Strains lacking the aspartic proteases Yps7 and Yps10 were also decreased in virulence in the fly model, an observation reminiscent of our recent finding that a yps1-11Δ strain lacks virulence in the Drosophila model (Quintin et al., 2013).
Bd has a demonstrated ability to respond quickly to novel hosts and environmental conditions through relatively rapid increases or decreases in virulence, which has likely contributed to its spread around the world.
