BER launches Environmental System Science Program. Visit our new website under construction!

U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


Structural Studies by LBNL Researcher Provides Insights into Regulation of Bacterial Gene Expression
Published: July 03, 2006
Posted: August 02, 2006

Many microbes use two-component signal transduction as a method of information processing to control their adaptive behaviors in response to changes in the environment. The transmitter component receives the initial signal and modifies the receiver domain of the second component, called a response regulator; the signal pathway is then turned on or off by the status of the response regulator. Microbial nitrogen assimilation and metabolism is regulated by this type of two-component signal relay, with the NtrC response regulator controlling nitrogen scavenging pathways and nitrogen fixation. Featured on the cover of the June 1, 2006, issue of Genes and Development, LBNL investigator Professor Eva Nogales and colleagues report x-ray and electron microscopy structural biology studies of NtrC that provide new insights into the mechanism of regulation of bacterial transcription and gene expression. When activated by phosphorylation of its receiver domain, NtrC assembles into a donut-like hexameric ring that encloses and binds to regulatory promoter DNA sequences. The resulting conformational change in the molecular machine that produces mRNA, s54-RNA polymerase, thereby activates the entire polymerase machinery to initiate transcription of the required nitrogen assimilation genes, to produce a metabolic response to the original signal about the cells nutrient status. This new model suggests that conformational dynamics are crucial for understanding how a transcriptional activator interacts with RNA polymerase to regulate gene expression.

Reference: Sacha De Carlo, Baoyu Chen, Timothy R. Hoover, Elena Kondrashkina, Eva Nogales, and B. Tracy Nixon (2006) The Structural Basis for Regulated Assembly and Function of the Transcriptional Activator NtrC, Genes & Dev 20 (11):14851495.

Contact: Arthur Katz, SC-23.2, (301) 903-4932
Topic Areas:

  • Research Area: Genomic Analysis and Systems Biology
  • Research Area: Microbes and Communities
  • Research Area: Structural Biology, Biomolecular Characterization and Imaging

Division: SC-33.2 Biological Systems Science Division, BER
      (formerly SC-23.2 Medical Sciences Division, OBER)

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Jan 11, 2022
No Honor Among Copper Thieves
Findings provide a novel means to manipulate methanotrophs for a variety of environmental and in [more...]

Dec 06, 2021
New Genome Editing Tools Can Edit Within Microbial Communities
Two new technologies allow scientists to edit specific species and genes within complex laborato [more...]

Oct 27, 2021
Fungal Recyclers: Fungi Reuse Fire-Altered Organic Matter
Degrading pyrogenic (fire-affected) organic matter is an important ecosystem function of fungi i [more...]

Oct 19, 2021
Microbes Offer a Glimpse into the Future of Climate Change
Scientists identify key features in microbes that predict how warming affects carbon dioxide emi [more...]

Aug 25, 2021
Assessing the Production Cost and Carbon Footprint of a Promising Aviation Biofuel
Biomass-derived DMCO has the potential to serve as a low-carbon, high-performance jet fuel blend [more...]

List all highlights (possible long download time)