Short-range DNA looping has been proposed to affect promoter activity in many bacterial species and operator configurations, but only few examples have been experimentally investigated in molecular detail. Here we present evidence for a metal-responsive DNA condensation mechanism controlled by the Helicobacter pylori ferric uptake regulator (Fur), an orthologue of the widespread Fur family of prokaryotic metal-dependent regulators. H. pylori Fur represses the transcription of the essential arsRS acid acclimation operon through iron-responsive oligomerization and DNA compaction, encasing the arsR transcriptional start site in a repressive macromolecular complex. A second metal-dependent regulator NikR functions as nickel-dependent anti-repressor at this promoter, antagonizing the binding of Fur to the operator elements responsible for the DNA condensation. The results allow unifying H. pylori metal ion homeostasis and acid acclimation in a mechanistically coherent model, and demonstrate, for the first time, the existence of a selective metal-responsive DNA compaction mechanism controlling bacterial transcriptional regulation.
Titolo: | Metal-responsive promoter DNA compaction by the ferric uptake regulator | |
Autore/i: | RONCARATI, DAVIDE; PELLICIARI, SIMONE; Doniselli, Nicola; Maggi, Stefano; VANNINI, ANDREA; VALZANIA, LUCA; MAZZEI, LUCA; ZAMBELLI, BARBARA; Rivetti, Claudio; DANIELLI, ALBERTO | |
Autore/i Unibo: | ||
Anno: | 2016 | |
Rivista: | ||
Digital Object Identifier (DOI): | http://dx.doi.org/10.1038/ncomms12593 | |
Abstract: | Short-range DNA looping has been proposed to affect promoter activity in many bacterial species and operator configurations, but only few examples have been experimentally investigated in molecular detail. Here we present evidence for a metal-responsive DNA condensation mechanism controlled by the Helicobacter pylori ferric uptake regulator (Fur), an orthologue of the widespread Fur family of prokaryotic metal-dependent regulators. H. pylori Fur represses the transcription of the essential arsRS acid acclimation operon through iron-responsive oligomerization and DNA compaction, encasing the arsR transcriptional start site in a repressive macromolecular complex. A second metal-dependent regulator NikR functions as nickel-dependent anti-repressor at this promoter, antagonizing the binding of Fur to the operator elements responsible for the DNA condensation. The results allow unifying H. pylori metal ion homeostasis and acid acclimation in a mechanistically coherent model, and demonstrate, for the first time, the existence of a selective metal-responsive DNA compaction mechanism controlling bacterial transcriptional regulation. | |
Data stato definitivo: | 2016-11-24T14:56:23Z | |
Appare nelle tipologie: | 1.01 Articolo in rivista |
File in questo prodotto:
File | Descrizione | Tipo | Licenza | |
---|---|---|---|---|
Roncarati_NatComms.pdf | Versione (PDF) editoriale | Licenza per Accesso Aperto. Creative Commons Attribuzione (CCBY) | Open Access Visualizza/Apri |