Linked Life Data

372753

Source:http://linkedlifedata.com/resource/pubmed/id/372753

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1979-6-29
pubmed:abstractText
A new class of mutants of E. coli exhibiting altered metabolism of ppGpp and pppGpp has been isolated, and mapped at a locus designated gpp, near min 83 on the genetic map. These mutants accumulate elevated levels of pppGpp during amino acid starvation or carbon source downshift, and exhibit a reduced rate of pppGpp degradation in vivo. The in vitro evidence suggests that the gpp mutants are defective in a 5'-nucleotidase, which specifically hydrolyzes pppGpp to ppGpp. Certain combinations of gpp and spoT mutations are inviable. A gpp spoT double mutant, constructed by employing a leaky spoT mutation, was found to have a slower rate of pppGpp degradation than the gpp mutant alone. This result indicates that spoT also participates in pppGpp degradation. The inviability of certain gpp spoT combinations is attributed to the inability of the double mutants to degrade pppGpp. This is supported by the observation that selection for increased growth rate on the double mutant results in the recovery of relA mutations. Various effects of the gpp mutation upon the pppGpp and ppGpp pools provide additional support for a scheme in which pppGpp is the major precursor of ppGpp.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
169
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
315-23
pubmed:dateRevised
2000-12-18
pubmed:meshHeading
pubmed:year
1979
pubmed:articleTitle
Mutants of Escherichia coli defective in the degradation of guanosine 5'-triphosphate, 3'-diphosphate (pppGpp).
pubmed:publicationType
Journal Article