EC Number   |
General Information |
Reference |
|---|
    2.7.6.5 | evolution |
the enzyme belongs to the RSH superfamily, which controls concentrations of the alarmones (p)ppGpp (guanosine penta- or tetra-phosphate) |
-, 739546 |
| 2.7.6.5 | evolution |
the enzyme RelA belongs to the RSH superfamily, also comprising members such as RelA/SpoT homologue, (p)ppGpp synthetase I, SpoT, and (p)ppGpp synthetase II. The RSH enzyme family controls concentrations of the alarmones (p)ppGpp (guanosine penta- or tetra-phosphate) |
737883 |
| 2.7.6.5 | malfunction |
GTP dysregulation in Bacillus subtilis cells lacking (p)ppGpp results in phenotypic amino acid auxotrophy and failure to adapt to nutrient downshift and regulate biosynthesis genes. Loss of the (p)ppGpp synthetase activity results in a failure of Bacillus subtilis to grow on minimal medium and causes the requirement for valine, leucine, isoleucine, threonine, and methionine, and a weaker requirement for arginine, histidine, and tryptophan addition |
-, 738529 |
| 2.7.6.5 | malfunction |
Mycobacterium tuberculosis strains expressing the synthetase-dead RelMtb H344Y mutant do not persist in mice. Deletion of a second predicted (p)ppGpp synthetase has no effect on pathogenesis, demonstrating. Expression of an allele encoding the hydrolase-dead RelMtb mutant, RelMtb H80A, decreases the growth rate of Mycobacterium tuberculosis and changes the colony morphology of the bacteria. RelMtb H80A expression during acute or chronic Mycobacterium tuberculosis infection in mice is lethal to the infecting bacteria. Phenotypes, overview |
-, 738524 |
| 2.7.6.5 | more |
mechanism and allosteric regulation of the highly cooperative enzyme from Bacillus subtilis, overview. Analysis of the catalytic mechanism of (p)ppGpp synthesis by oligomeric and highly cooperative small alarmone synthetase 1 (SAS1) at atomic resolution, structural and biochemical analysis reveals that only pppGpp, but not ppGpp, positively affects the activity of the enzyme |
-, 739546 |
| 2.7.6.5 | physiological function |
(p)ppGpp synthetase interacts with both GTPase Era and DEAD-box RNA helicase CshA, influences the enzymatic activity of Era and CshA and is important for rRNA processing |
762200 |
| 2.7.6.5 | physiological function |
guanosine 3'-diphosphate 5'-triphosphate, (p)ppGpp, synthesis is required for amino acid prototrophy |
-, 738529 |
| 2.7.6.5 | physiological function |
guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp), collectively termed (p)ppGpp, act as alarmones that globally reprogram cellular physiology during various stress conditions. Enzymes of the RelA/SpoT homology (RSH) family synthesize (p)ppGpp by transferring diphosphate from ATP to GDP or GTP. ppGpp and pppGpp execute different functional roles |
-, 739546 |
| 2.7.6.5 | physiological function |
in Mycobacterium tuberculosis, the stringent response to amino acid starvation is mediated by the enzyme Rel (RelMtb), which transfers a diphosphate from ATP to GDP or GTP to synthesize guanosine 3'-diphosphate 5'-diphosphate (ppGpp) and guanosine 3'-diphosphate 5'-triphosphate (pppGpp), respectively. (p)ppGpp then influences numerous metabolic processes. RelMtb also encodes a second, distinct catalytic domain that hydrolyzes (p)ppGpp into diphosphate and GDP or GTP. RelMtb is required for chronic Mycobacterium tuberculosis infection in C57BL/6 mice. The RelMtb (p)ppGpp synthetase activity is required for maintaining bacterial titers during chronic infection, RelMtb is the major contributor to (p)ppGpp production during infection, RelMtb (p)ppGpp hydrolase activity is essential for acute and chronic infection of mice |
-, 738524 |
| 2.7.6.5 | physiological function |
in vivo, under relaxed conditions, as well as in vitro, the C-terminal regulatory domain CTD inhibits synthetase activity but is not required for hydrolase activity. Under stringent conditions, the CTD is essential for (p)ppGpp synthesis. A mutant lacking the CTD exhibits net hydrolase activity when expressed in Staphylococcus aureus but net (p)ppGpp synthetase activity when expressed in Escherichia coli. The conserved TGS and DC motifs within the CTD are required for correct stringent response, whereas the conserved ACT motif is dispensable. The enzyme primarily exists in a synthetase-off/hydrolase-on state |
751910 |
