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Updated: Jun 23, 2026
09:51
Rapid Verification of Terminators Using the pGR-Blue Plasmid and Golden Gate Assembly
Published on: April 25, 2016
Occurrence, divergence and evolution of intrinsic terminators across eubacteria
Anirban Mitra1, Kandavelmani Angamuthu, Hanasoge Vasudevamurthy Jayashree
1Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India.
Genomics
|April 28, 2009
Summary
Eubacteria extensively use intrinsic transcription termination, but canonical E. coli terminators are rare. Diverse terminator structures are conserved across bacterial phyla, influenced by genomic GC content and Rho factor.
Area of Science:
- Genomics and Molecular Biology
- Bioinformatics and Computational Biology
Background:
- Canonical intrinsic transcription terminators in Escherichia coli feature a palindromic sequence followed by a U-rich trail.
- An underrepresentation of these canonical terminators in eubacterial genomes prompted the development of predictive algorithms.
Purpose of the Study:
- To develop and apply an improved algorithm (GeSTer) for rapid and accurate prediction of putative intrinsic transcription terminators in eubacterial genomes.
- To analyze the prevalence, structure, and conservation of intrinsic terminators across a wide range of eubacterial species.
Main Methods:
- Utilized an improved version of the GeSTer algorithm to analyze 378 eubacterial genome sequences.
- Investigated the correlation between terminator structure, genomic GC content, and the presence of the Rho termination factor.
Main Results:
- Canonical E. coli-type terminators are not universally abundant; atypical terminators lacking a U-trail are widespread across eubacteria.
- Different bacterial phyla exhibit conserved preferences for specific terminator structures, correlating with genomic GC content and Rho factor presence.
- A significant proportion (60-70%) of identified terminators display optimized stem-length and thermodynamic stability (DeltaG).
Conclusions:
- Eubacteria extensively employ intrinsic transcription termination, demonstrating considerable structural, positional, and prevalence divergence.
- The findings highlight the evolutionary adaptability of intrinsic termination mechanisms in response to genomic and cellular factors.
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