Additionally, among the genes with basic cellular functions conserved in all Legionellales, CRt has lost three transcriptional regulators; one of the sigma factors, rpoS (stress response) and the two regulators oxyR, the oxidative stress regulator, and nrdR, a repressor of ribonucleotide reductases.
This protein, besides not being linked to conidiation, has been shown to function as an oxidative response regulator and shares the signature phenylalanine-containing PAP subfamily bZip DBD (F19) [35] with Yap1 and Pap1 rather than the distinctive H19 DBD of FlbB [63].
Thus, oxidative stress regulator OxyR mediates the protective effect of vgb under oxidative stress [ 19].
Cells lacking the key oxidative stress regulator OxyR showed reduced survival in the presence of adrenaline and complete restoration of growth upon addition of manganese.
In E. coli, the protective role of VHb is mediated through oxidative stress regulator OxyR, which in turn activates VHb biosynthesis [ 19, 20].
First, although the C-terminal regions of the FlbB orthologs likely function similarly to these two oxidative response regulators (i.e., mechanistic homology) is FlbB, in fact, a functional homolog?
This study revealed a potential therapeutic use in ALF of in vivo siRNA technology targeted to oxidative stress regulators.
The overexpression of superoxide dismutase (sodA) increased intracellular H2O2 concentrations and inhibited E. coli fatty-acid utilization, whereas overexpression of an oxidative-stress regulator (oxyS) decreased intracellular H2O2 concentrations and promoted E. coli fatty acid utilization and l-lysine production.
To determine which ROS has the greatest negative effect on fatty acid utilization in E. coli, we constructed expression plasmids harboring the sodA gene encoding the O2∙– scavenger dismutase or the oxyS gene encoding an oxidative-stress regulator and introduced them into the wild-type strain MG1655.
This link is of particular interest, since it was recently reported that upon oxidative stress the regulator Stb5 shunts carbohydrate metabolism from glycolysis to the pentose phosphate pathway [11].
