When complexed with Escherichia coli RNA polymerase core enzyme, purified RpoI protein of Rhizobium leguminosarum initiated transcription in vitro from promoters of the vbsADL and vbsGSO operons, which are needed to synthesise the siderophore vicibactin. There is a single transcription initiation site for rpoI, regardless of whether the cells are grown in Fe-replete or Fe-depleted media, but levels of rpoI mRNA were reduced, though not abolished, in the presence of Fe. Unlike PvdS, a similar Pseudomonas sigma factor needed to transcribe genes involved in pyoverdine synthesis, RpoI transcribes vbsADL and vbsGSO in the absence of the cognate siderophore. The RpoI sigma factor is not required for transcription of rpoI.

Download full-text PDF

Source
http://dx.doi.org/10.1016/S0378-1097(03)00386-0DOI Listing

Publication Analysis

Top Keywords

sigma factor
12
vbsadl vbsgso
8
rpoi
7
ecf sigma
4
factor rpoi
4
rpoi leguminosarum
4
leguminosarum initiates
4
transcription
4
initiates transcription
4
transcription vbsgso
4

Similar Publications

Background: Therapeutic drug monitoring is important for optimizing anti-tumor necrosis factor-α (TNF-α) therapy in inflammatory bowel disease. However, the exposure-response relationship has never been assessed in pouchitis.

Aims: To explore associations between anti-TNF-α drug concentration and pouchitis disease activity in patients with a background of ulcerative colitis.

View Article and Find Full Text PDF

Genome-wide identification of binding profiles for DNA-binding proteins from the limited number of intracellular pathogens in infection studies is crucial for understanding virulence and cellular processes but remains challenging, as the current ChIP-exo is designed for high-input bacterial cells (>1010). Here, we developed an optimized ChIP-mini method, a low-input ChIP-exo utilizing a 5,000-fold reduced number of initial bacterial cells and an analysis pipeline, to identify genome-wide binding dynamics of DNA-binding proteins in host-infected pathogens. Applying ChIP-mini to intracellular Salmonella Typhimurium, we identified 642 and 1,837 binding sites of H-NS and RpoD, respectively, elucidating changes in their binding position and binding intensity during infection.

View Article and Find Full Text PDF

The Possible Crystallization Process in the Origin of Bacteria, Archaea, Viruses, and Mobile Elements.

Biology (Basel)

December 2024

Division of Biochemistry, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan.

We propose a hypothesis for the simultaneous emergence of bacteria, archaea, viruses, and mobile elements by sequential and concrete biochemical pathways. The emergence process can be considered analogous to crystallization, where genetic and biochemical systems stabilize as organisms evolve from their common ancestor, the LUCA, which was a non-free-living pool of single operon type genomes including double-stranded (ds) DNA at an ancient submarine alkaline vent. Each dsDNA operon was transcribed by different systems in σ, TFIIB, or TBP genomes.

View Article and Find Full Text PDF

Long term substantial impacts of historic Chlor-Alkali production as a newly recognized source of polyhalogenated carbazoles in aquatic environments.

J Environ Sci (China)

July 2025

State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; University of Chinese Academy of Sciences, Beijing 100049, China.

Bottom sediments of the North American Great Lakes are characterized by a high loading (over 3,000 tonnes) of polyhalogenated carbazoles (PHCZs). The origin of this environmental contaminant loading is unclear. Here, we first examined PHCZs levels and profiles in sediment, lotus, and fish from the Ya-Er Lake (China) that has been under the influence of an obsolete chlor-alkali facility for forty years and discovered substantial PHCZs contamination.

View Article and Find Full Text PDF

and are two phylogenetically related bacterial pathogens that exhibit extreme intrinsic resistance when they enter into a dormancy-like state. This enables both pathogens to survive extended periods in growth-limited environments. Survival is dependent upon their ability to undergo developmental transitions into two phenotypically distinct variants, one specialized for intracellular replication and another for prolonged survival in the environment and host.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!