Transcriptional activation of the Escherichia coli bgl operon: negative regulation by DNA structural elements near the promoter

Molecular Microbiology
J SinghS Mahadevan

Abstract

The bgl operon of Escherichia coli is transcriptionally inactive in wild-type cells. DNA insertion sequences (IS) constitute a major class of spontaneous mutations that activate the cryptic bgl promoter. In an attempt to study the molecular mechanism of activation mediated by insertion sequences, transcription of the bgl promoter was carried out in vitro. Stimulation of transcription is observed when a plasmid containing an insertionally activated bgl promoter is used as a template in the absence of proteins other than RNA polymerase. Deletions that remove sequences upstream of the bgl promoter, and insertion of a 1.2 kb DNA fragment encoding resistance to kanamycin, activate the promoter. Point mutations within a region of dyad symmetry upstream of the promoter, which has the potential to extrude into a cruciform structure under torsional stress, also lead to activation. Introduction of a sequence with dyad symmetry, upstream of an activated bgl promoter carrying a deletion of upstream sequences, results in a fourfold reduction in transcription. These results suggest that the cryptic nature of the bgl promoter is because of the presence of DNA structural elements near the promoter that negatively affect transcription.

Citations

Jun 27, 2001·Journal of Biosciences·A Gulati, S Mahadevan
Jun 24, 2000·Research in Microbiology·E Tamburini, G Mastromei
May 14, 1999·Current Opinion in Microbiology·X Dai, L B Rothman-Denes
Apr 12, 2000·Molecular Microbiology·A Caramel, K Schnetz
Jul 8, 2000·The Plant Journal : for Cell and Molecular Biology·L V SidorenkoT Peterson
Nov 5, 2003·Journal of Bacteriology·Mario Alberto Flores-ValdezEdmundo Calva
Dec 2, 2010·Microbiology and Molecular Biology Reviews : MMBR·David BikardDidier Mazel
Sep 17, 2008·FEMS Microbiology Letters·Ranjna MadanSubramony Mahadevan
Sep 24, 2013·Journal of Molecular Biology·Martina RauschmeierKirsten Jung
Jun 20, 2014·Journal of Molecular Biology·Eric Lindner, Stephen H White
Oct 4, 2016·Archives of Microbiology·Asha Mary JosephSubramony Mahadevan
Feb 10, 2018·Molecular Microbiology·Aathmaja Anandhi Rangarajan, Karin Schnetz
Jul 15, 2015·Journal of Bacteriology·Karen A Fahrner, Howard C Berg
Dec 3, 2014·Journal of Bacteriology·Parisa ZangouiSubramony Mahadevan
Mar 7, 2014·Microbiology and Molecular Biology Reviews : MMBR·Elise Darmon, David R F Leach
Mar 5, 2020·Archives of Microbiology·Kartika Vashishtha, S Mahadevan
Sep 8, 1998·Microbiology and Molecular Biology Reviews : MMBR·M K Berlyn

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