Words similar to pyogenes
Example sentences for: pyogenes
How can you use “pyogenes” in a sentence? Here are some example sentences to help you improve your vocabulary:
Taken together, these studies suggest a complex network of positive and negative regulatory pathways controlling key virulence genes in S. pyogenes that can be activated or inactivated in response to certain biological pressures in the infected host.
Previous studies from our laboratory have consistently demonstrated loss of the SpeB phenotype in S. pyogenes isolates injected in a skin air sac and recovered from the organs of lethally infected mice [ 10 16 ] . This selection was not associated with loss of β-hemolysis but was associated with over-expression of M and M-related proteins, which in turn are predictive of the invasive potential of the organism in a skin infection model [ 16 ] . Based on the phenotypic characteristics of the kidney-recovered variant (β-hemolytic positive, M and M-related protein positive and SpeB negative) we predicted that this variant would be as virulent or more virulent than the wild type organism in the mouse skin infection model.
In related studies, the selection of stable variants of either wild type or mutant S. pyogenes isolates was not consistently observed when the organism was injected i.p.
In studies using a tissue chamber model, Kotb and colleagues have noted changes in expression of key virulence factors as a function of time [ 40 ] . Thus, it is possible that the in vivo events leading to selection of stable S. pyogenes variants may require a dynamic interaction with the host and that only under certain experimental conditions will the stable variant population be recovered.
The ability of biological pressures in the mouse to select stable variants of S. pyogenes expressing different patterns of virulence factors suggest the existence of more complex regulatory pathway than is currently envisaged.
Loading...