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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Evolution of the NadR regulon in Enterobacteriaceae
Anna V Gerasimova1, Mikhail S Gelfand
1Laboratory of Bioinformatics, State Scientific Center GOSNIIGenetika, 1-iy Dorozhny proezd 1, Moscow, 113545, Russia. a_gerasimova@yahoo.com
Journal of Bioinformatics and Computational Biology
|August 4, 2005
Summary
The NadR regulon, controlling essential NAD biosynthesis in Enterobacteriaceae, shows significant variation even between closely related species. Comparative genomics identified new regulon members, highlighting genomic plasticity in metabolic pathways.
Area of Science:
- Microbiology
- Genomics
- Metabolic Engineering
Background:
- The nicotinamide adenine dinucleotide (NAD) biosynthetic pathway is crucial for cellular metabolism.
- While well-understood in *E. coli* and *S. typhi*, the regulation of this pathway in other Enterobacteriaceae is less characterized.
- The NadR protein is a key regulator of NAD biosynthesis.
Purpose of the Study:
- To describe the NadR regulon across various Enterobacteriaceae species using comparative genomics.
- To identify novel candidate genes regulated by NadR.
- To investigate the evolutionary divergence of simple metabolic regulons in closely related bacterial genomes.
Main Methods:
- Comparative genomics analysis of Enterobacteriaceae genomes.
- Bioinformatic identification of potential NadR binding sites and co-regulated genes.
- Phylogenetic analysis of regulon members.
Main Results:
- The NadR regulon was characterized in a broader range of Enterobacteriaceae.
- Several new candidate genes belonging to the NadR regulon were identified.
- Significant differences in regulon composition were observed even among closely related species.
Conclusions:
- The NadR regulon exhibits substantial evolutionary variation within the Enterobacteriaceae family.
- Comparative genomics is a powerful tool for dissecting metabolic pathway regulation and identifying novel regulatory interactions.
- Even essential metabolic pathways can be subject to rapid evolutionary changes in their regulatory networks.
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