PMID:15317765
| Citation |
King, T, Ishihama, A, Kori, A and Ferenci, T (2004) A regulatory trade-off as a source of strain variation in the species Escherichia coli. J. Bacteriol. 186:5614-20 |
|---|---|
| Abstract |
There are few existing indications that strain variation in prokaryotic gene regulation is common or has evolutionary advantage. In this study, we report on isolates of Escherichia coli with distinct ratios of sigma factors (RpoD, sigmaD, or sigma70 and RpoS or sigmaS) that affect transcription initiated by RNA polymerase. Both laboratory E. coli K-12 lineages and nondomesticated isolates exhibit strain-specific endogenous levels of RpoS protein. We demonstrate that variation in genome usage underpins intraspecific variability in transcription patterns, resistance to external stresses, and the choice of beneficial mutations under nutrient limitation. Most unexpectedly, RpoS also controlled strain variation with respect to the metabolic capability of bacteria with more than a dozen carbon sources. Strains with higher sigmaS levels were more resistant to external stress but metabolized fewer substrates and poorly competed for low concentrations of nutrients. On the other hand, strains with lower sigmaS levels had broader nutritional capabilities and better competitive ability with low nutrient concentrations but low resistance to external stress. In other words, RpoS influenced both r and K strategist functions of bacteria simultaneously. The evolutionary principle driving strain variation is proposed to be a conceptually novel trade-off that we term SPANC (for "self-preservation and nutritional competence"). The availability of multiple SPANC settings potentially broadens the niche occupied by a species consisting of individuals with narrow specialization and reveals an evolutionary advantage offered by polymorphic regulation. Regulatory diversity is likely to be a significant contributor to complexity in a bacterial world in which multiple sigma factors are a universal feature. |
| Links |
PubMed PMC516835 Online version:10.1128/JB.186.17.5614-5620.2004 |
| Keywords |
Acids/pharmacology; Adaptation, Physiological; Bacterial Proteins/analysis; Bacterial Proteins/genetics; Bacterial Proteins/physiology; Biological Evolution; Catalase/analysis; Catalase/metabolism; DNA-Directed RNA Polymerases/analysis; DNA-Directed RNA Polymerases/genetics; DNA-Directed RNA Polymerases/physiology; Energy Metabolism; Escherichia coli/genetics; Escherichia coli/physiology; Escherichia coli Proteins/genetics; Escherichia coli Proteins/physiology; Gene Expression Regulation, Bacterial; Genetic Variation; Growth Inhibitors/pharmacology; Osmotic Pressure; Selection, Genetic; Sigma Factor/analysis; Sigma Factor/genetics; Sigma Factor/physiology; Transcription, Genetic; beta-Galactosidase/metabolism |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.