Helicobacter pylori: a eubacterium lacking the stringent response.

Abstract

Accumulation of 16S rRNA and production of guanosine polyphosphates (pppGpp and ppGpp) were studied during amino acid starvation in three wild-type strains of Helicobacter pylori. All strains exhibit a relaxed phenotype with respect to accumulation of 16S rRNA. This constitutes the first example of a wild-type eubacterium showing a relaxed phenotype. The guanosine polyphosphate levels do not rise as a result of amino acid starvation, as expected for relaxed organisms. However, in both growing and starved cells, basal levels of the two polyphosphates appeared to be present, demonstrating that the enzymatic machinery for guanosine polyphosphate production is present in this organism. These findings are discussed within the framework of the hypothesis that stringent control is a physiological control mechanism more important for the fitness of prokaryotes growing in the general environment than for those that inhabit protected niches.

• Authors: G L Scoarughi, C Cimmino, P Donini
• Journal: Journal of bacteriology (J Bacteriol) Vol. 181 Issue 2 Pg. 552-5 (Jan 1999) ISSN: 0021-9193 [Print] United States
• PMID: 9882669 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Amino Acids
• Bacterial Proteins
• RNA, Ribosomal, 16S
• serine hydroxamate
• Guanosine Tetraphosphate
• Guanosine Pentaphosphate
• Serine
• Mupirocin

Topics

• Amino Acids (metabolism)
• Bacterial Proteins (biosynthesis, genetics)
• Guanosine Pentaphosphate (biosynthesis)
• Guanosine Tetraphosphate (biosynthesis)
• Helicobacter pylori (genetics, growth & development, metabolism)
• Kinetics
• Mupirocin (pharmacology)
• Protein Biosynthesis (drug effects)
• RNA, Ribosomal, 16S (biosynthesis, genetics)
• Serine (analogs & derivatives, pharmacology)
• Species Specificity
• Time Factors
• Transcription, Genetic (drug effects)