pepD is directly regulated by the stress-responsive two-component signal transduction system MprAB and indirectly by extracytoplasmic function (ECF) sigma factor SigE. Loss of PepD also impacts expression of other stress-responsive determinants in M. tuberculosis.
This system directly regulates expression of numerous stress-responsive determinants in M. tuberculosis including ECF sigma factors sigE and sigB, alpha crystallin gene acr2, and serine protease pepD [3], [4], [5], [6].
These phenotypes, coupled with the observation that pepD deletion results in upregulation of numerous stress-responsive determinants in M. tuberculosis under physiological conditions including sigE [12], underscores the complex regulation and multifaceted activity of this protein.
These virulence factors include surface proteins that allow adhesion to host components such as fibrinogen (Clumping Factors, ClfAand B) or fibronectin (fibronectin binding proteins, FnBP A and B),, and proteins which scavenge nutrients that are normally sequestered in vivo (such as iron-responsive surface determinants, IsdA and B).
The genes encoding clumping factor (Clf) A, ClfB, and iron-responsive surface-determinant (Isd) A were detected in all isolates.
(4) S. aureus exhibits a preference for heme as an iron source during infection(6) and encodes a heme uptake system called the iron-responsive surface determinant (Isd) system, which is able to exploit the heme and hemoprotein resources of the host.
Throughout the 1990s, partnerships were espoused as a way to ensure that health systems were responsive to the social determinants of health [ 13, 18].
Nevertheless, the available data in experimental animals indicate that Hedgehog-responsive myofibroblasts are key determinants of hepatic deiodinase expression and thereby, local TH activity during liver injury.
Interestingly, in two cases the genetic determinants responsible for the QTL phenotype have been linked to a single underlying gene and homologues of these two genes were both present in the list of putative drought-responsive Musa transcripts.
Hepatic gene expression profiles were analyzed using a custom, focused oligonucleotide DNA microarray, the HC ToxArray™, containing toxin-responsive and toxicologically-determinant genes.
