PMID:2687246
| Citation |
Vogler, AP, Trentmann, S and Lengeler, JW (1989) Alternative route for biosynthesis of amino sugars in Escherichia coli K-12 mutants by means of a catabolic isomerase. J. Bacteriol. 171:6586-92 |
|---|---|
| Abstract |
By inserting a lambda placMu bacteriophage into gene glmS encoding glucosamine 6-phosphate synthetase (GlmS), the key enzyme of amino sugar biosynthesis, a nonreverting mutant of Escherichia coli K-12 that was strictly dependent on exogenous N-acetyl-D-glucosamine or D-glucosamine was generated. Analysis of suppressor mutations rendering the mutant independent of amino sugar supply revealed that the catabolic enzyme D-glucosamine-6-phosphate isomerase (deaminase), encoded by gene nagB of the nag operon, was able to fulfill anabolic functions in amino sugar biosynthesis. The suppressor mutants invariably expressed the isomerase constitutively as a result of mutations in nagR, the locus for the repressor of the nag regulon. Suppression was also possible by transformation of glmS mutants with high-copy-number plasmids expressing the gene nagB. Efficient suppression of the glmS lesion, however, required mutations in a second locus, termed glmX, which has been localized to 26.8 min on the standard E. coli K-12 map. Its possible function in nitrogen or cell wall metabolism is discussed. |
| Links | |
| Keywords |
Aldose-Ketose Isomerases; Carbohydrate Epimerases/genetics; Carbohydrate Epimerases/metabolism; Escherichia coli/enzymology; Escherichia coli/genetics; Genes, Bacterial; Genetic Markers/analysis; Genotype; Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing)/genetics; Hexosamines/biosynthesis; Mutation; Operon; Phenotype; Plasmids; Restriction Mapping; Suppression, Genetic; Transduction, 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.