relA [Thu Nov 24 2016 18:04:42 GMT+0100 (CET)]

GTP pyrophosphokinase (stringent response)

locus: BSU27600

pI: 6.00

mw: 84.00 kDa

function: synthesis and degradation of (p)ppGpp,
triggering the stringent response

product: GTP pyrophosphokinase

essential: no

ec: 2.7.6.5

synonyms

Genomic Context

categories

• [category|SW 2|Metabolism] → [category|SW 2.5|Nucleotide metabolism] → [category|SW 2.5.3|Metabolism of signalling nucleotides]

[SW|Categories] containing this gene/protein

• [SW|metabolism of signalling nucleotides]

Gene

Coordinates on the chromosome (coding sequence): 2,820,529 -> 2,822,733

Phenotypes of a mutant

• requirement for valine [Pubmed|24163341]
• a ''[protein|search|relA] [protein|search|sasA] [protein|search|sasB]'' triple mutant requires branched chain amino acids, methionine and threonine for growth, the requirement can be suppressed by reduced expression of ''[protein|search|guaB]'' or inactivation of ''[protein|search|codY]'' [Pubmed|24163341]
• a ''[protein|search|relA] [protein|search|sasA] [protein|search|sasB]'' triple mutant acquires suppressor mutations in ''[protein|search|guaA], [protein|search|guaB], [protein|search|gmk]'' or inactivation of ''[protein|search|codY]'' [Pubmed|24682323,24163341]
• mutation in ''[protein|search|relA]'' results in increased motility and chaining [Pubmed|25331430]
• ''[protein|search|relA]'' mutation increases flagellin production via elevated [protein|search|SigD] level [Pubmed|25331430]

The protein

Catalyzed reaction/ biological activity

• ATP GTP = AMP guanosine 3'-diphosphate 5'-triphosphate (according to Swiss-Prot)

Protein family

• relA/spoT family (according to Swiss-Prot)

[SW|Domains]

• N-terminal ppGpp hydrolase domain [Pubmed|24163341]
• central ppGpp synthetase domain [Pubmed|24163341]

Effectors of protein activity

• the interaction with [SW|ComGA] inhibits the hydrolysis of ppGpp [Pubmed|25899641]

Structure

• [PDB|1VJ7] (N-terminal catalytic fragment, from ''Streptococcus equisimilis'', 60% identity) [Pubmed|15066282]

[SW|Interactions]

• [protein|search|RelA]-[SW|ComGA], required for the inhibition of rRNA synthesis in the K-state [Pubmed|25899641]

Expression and Regulation

Operon

• ''[protein|search|relA]-[protein|search|dtd]'' [Pubmed|9383190]

Biological materials

Mutant

• ''[protein|search|relA]'' mutant [Pubmed|9383190] - note that ''[protein|search|relA]'' mutants are prone to suppressor mutations in the ''[protein|search|ywaC]'' or ''[protein|search|yjbM]'' loci [Pubmed|18670626]
• GP2066 (''[SW|sasA] [SW|sasB] [SW|relA]::mls''), available in [SW|Jörg Stülke]'s lab

Labs working on this gene/protein

• [SW|Mohamed Marahiel], Marburg University, Germany [http://www.uni-marburg.de/fb15/fachgebiete/bio/marahiel?language_sync=1 homepage]
• Jue D Wang, University of Wisconsin–Madison [https://www.researchgate.net/profile/Jue_Wang8 ResearchGate-Profile]

References

Reviews

• 27149325

Original publications

• 25331430,9383190,10209741,24489751,19447912,13129942,12372825,12081964,11948165,12419222,23028324,24163341,24682323,25899641,15066282,27775002