PMID:14973046
| Citation |
Bausch, C, Ramsey, M and Conway, T (2004) Transcriptional organization and regulation of the L-idonic acid pathway (GntII system) in Escherichia coli. J. Bacteriol. 186:1388-97 |
|---|---|
| Abstract |
The genetic organization of the idn genes that encode the pathway for L-idonate catabolism was characterized. The monocistronic idnK gene is transcribed divergently from the idnDOTR genes, which were shown to form an operon. The 215-bp regulatory region between the idnK and idnD genes contains promoters in opposite orientation with transcription start sites that mapped to positions -26 and -29 with respect to the start codons. The regulatory region also contains a single putative IdnR/GntR binding site centered between the two promoters, a CRP binding site upstream of idnD, and an UP element upstream of idnK. The genes of the L-idonate pathway were shown to be under catabolite repression control. Analysis of idnD- and idnK-lacZ fusions in a nonpolar idnD mutant that is unable to interconvert L-idonate and 5-ketogluconate indicated that either compound could induce the pathway. The L-idonate pathway was first characterized as a subsidiary pathway for D-gluconate catabolism (GntII), which is induced by D-gluconate in a GntI (primary gluconate system) mutant. Here we showed that the idnK and idnD operons are induced by D-gluconate in a GntI system mutant, presumably by endogenous formation of 5-ketogluconate from D-gluconate. Thus, the regulation of the GntII system is appropriate for this pathway, which is primarily involved in L-idonate catabolism; the GntII system can be induced by D-gluconate under conditions that block the GntI system. |
| Links | |
| Keywords |
Electrophoresis, Gel, Two-Dimensional; Escherichia coli/genetics; Escherichia coli/growth & development; Escherichia coli/metabolism; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Gene Expression Regulation, Bacterial; Oligonucleotide Array Sequence Analysis; Operon; Promoter Regions, Genetic; Sugar Acids/metabolism; Transcription, Genetic |
| 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.
