Loading...
  • heme
  • Hx-dependent uptake of extracellular heme can lead to the deactivation of Bach1 repression which leads to the transcriptional activation of antioxidant heme oxygenase-1 gene. (wikipedia.org)
  • Deletion of the hemopexin or heme oxygenase-2 gene can aggravate brain injury followed by stroma-free hemoglobin-induced intracerebral haemorrhage. (wikipedia.org)
  • normally
  • Standard glutamic acid-histidine-fructose medium, preincubated for 23 h to remove l-glutamate, allowed the synthesis of actinomycin D and tryptophan oxygenase by cells at a stage of growth normally considered too early for antibiotic production. (semanticscholar.org)
  • cells
  • The transfer of cells to this artificial preincubation medium resulted in the appearance of tryptophan oxygenase as early as 19 h before normal synthesis occurred, eliminating the possibility that an inducer molecule is synthesized and excreted during the preincubation period. (semanticscholar.org)
  • Inhibition of cell proliferation induced by the tryptophan catabolites resulting from IDO activity was selective, applying only to cells undergoing activation. (nih.gov)
  • activity
  • The results of these studies suggest that the increase in tryptophan oxygenase activity before the onset of actinomycin D synthesis, as well as the synthesis of actinomycin D itself, is due to a release from l-glutamate catabolite repression. (semanticscholar.org)
  • effect
  • We suggest that IDO exerts its effect on cell proliferation by (i) starting the cascade of biochemical reactions that produce the three catabolites and by (ii) enhancing their inhibitory potential by depriving the extracellular microenvironment of tryptophan. (nih.gov)
  • presence
  • In the presence of tryptophan, only L-kynurenine and picolinic acid inhibit cell proliferation. (nih.gov)
  • In the absence of tryptophan inhibition induced by L-kynurenine and picolinic acid was observed at concentrations below the lowest concentration that was effective in the presence of tryptophan, and quinolinic acid acquired some inhibitory capacity. (nih.gov)
  • completely
  • The proteins are completely helical, and a flexible loop, involved in L-tryptophan binding, is observed just outside the active-site pocket. (wikipedia.org)