RRC ID 33558
Author Nanamiya H, Kasai K, Nozawa A, Yun CS, Narisawa T, Murakami K, Natori Y, Kawamura F, Tozawa Y.
Title Identification and functional analysis of novel (p)ppGpp synthetase genes in Bacillus subtilis.
Journal Mol Microbiol
Abstract Bacterial alarmone (p)ppGpp, is a global regulator responsible for the stringent control. Two homologous (p)ppGpp synthetases, RelA and SpoT, have been identified and characterized in Escherichia coli, whereas Gram-positive bacteria such as Bacillus subtilis have been thought to possess only a single RelA-SpoT enzyme. We have now identified two genes, yjbM and ywaC, in B. subtilis that encode a novel type of alarmone synthetase. The predicted products of these genes are relatively small proteins ( approximately 25 kDa) that correspond to the (p)ppGpp synthetase domain of RelA-SpoT family members. A database survey revealed that genes homologous to yjbM and ywaC are conserved in certain bacteria belonging to Firmicutes or Actinobacteria phyla but not in other phyla such as Proteobacteria. We designated the proteins as small alarmone synthetases (SASs) to distinguish them from RelA-SpoT proteins. The (p)ppGpp synthetase function of YjbM and YwaC was confirmed by genetic complementation analysis and by in vitro assay of enzyme activity. Molecular genetic analysis also revealed that ywaC is induced by alkaline shock, resulting in the transient accumulation of ppGpp. The SAS proteins thus likely function in the biosynthesis of alarmone with a mode of action distinct from that of RelA-SpoT homologues.
Volume 67(2)
Pages 291-304
Published 2008-1-1
DOI 10.1111/j.1365-2958.2007.06018.x
PMID 18067544
MeSH Amino Acid Sequence Arginine / analogs & derivatives Arginine / metabolism Bacillus subtilis / classification Bacillus subtilis / enzymology Bacillus subtilis / genetics* Bacterial Proteins / chemistry Bacterial Proteins / genetics* Bacterial Proteins / metabolism* Escherichia coli / genetics Escherichia coli Proteins / chemistry Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism Gene Expression Regulation, Bacterial Genetic Complementation Test Guanosine Tetraphosphate / biosynthesis Ligases / chemistry Ligases / genetics* Ligases / metabolism* Ligases / physiology Molecular Sequence Data Mutation Phylogeny Sequence Alignment Transcription, Genetic
IF 3.649
Times Cited 135
Prokaryotes B. subtilis MBS8 MBS9 MBS10 MBS11 MBS12 MBS13 MBS14