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Full-Text Articles in Molecular Biology
Aromatic Acid Metabolites Of Escherichia Coli K-12 Can Induce The Marrab Operon, Lon Chubiz, Christopher Rao
Aromatic Acid Metabolites Of Escherichia Coli K-12 Can Induce The Marrab Operon, Lon Chubiz, Christopher Rao
Biology Department Faculty Works
MarR is a key regulator of the marRAB operon involved in antibiotic resistance and solvent stress tolerance in Escherichia coli. We show that two metabolic intermediates, 2,3-dihydroxybenzoate and anthranilate, involved in enterobactin and tryptophan biosynthesis, respectively, can activate marRAB transcription. We also found that a third intermediate involved in ubiquinone biosynthesis, 4-hydroxybenzoate, activates marRAB transcription in the absence of TolC. Of the three, however, only 2,3-dihydroxybenzoate directly binds MarR and affects its activity.
Rna Processing Of Nitrogenase Transcripts In The Cyanobacterium Anabaena Variabilis, Justin Ungerer, Brenda Pratte, Teresa Thiel
Rna Processing Of Nitrogenase Transcripts In The Cyanobacterium Anabaena Variabilis, Justin Ungerer, Brenda Pratte, Teresa Thiel
Biology Department Faculty Works
Little is known about the regulation of nitrogenase genes in cyanobacteria. Transcription of the nifH1 and vnfH genes, encoding dinitrogenase reductases for the heterocyst-specific Mo-nitrogenase and the alternative V-nitrogenase, respectively, was studied by using a lacZ reporter. Despite evidence for a transcription start site just upstream of nifH1 and vnfH, promoter fragments that included these start sites did not drive the transcription of lacZ and, for nifH1, did not drive the expression of nifHDK1. Further analysis using larger regions upstream of nifH1 indicated that a promoter within nifU1 and a promoter upstream of nifB1 both contributed to expression of nifHDK1, …