Related Experiment Video

Updated: Aug 11, 2026

Engineering Adherent Bacteria by Creating a Single Synthetic Curli Operon
15:28

Engineering Adherent Bacteria by Creating a Single Synthetic Curli Operon

Published on: November 16, 2012

The regulation of pap and type 1 fimbriation in Escherichia coli

I C Blomfield1

  • 1Research School of Biosciences, University of Kent at Canterbury, Canterbury, Kent, CT2 7NJ, UK. I.C.Blomfield@ukc.ac.uk

Advances in Microbial Physiology
|July 14, 2001
PubMed

Insights

Escherichia coli uses two distinct mechanisms, nucleoprotein complexes for pap and DNA inversion for fim, to regulate fimbrial adhesin expression in response to environmental cues.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Bacterial Pathogenesis

Background:

  • Bacterial pathogens utilize fimbrial adhesins for host mucosa binding, a crucial step in infection.
  • Escherichia coli employs various fimbrial adhesins as virulence factors.
  • Understanding the regulation of these adhesins is key to combating bacterial infections.

Purpose of the Study:

  • To describe the regulatory mechanisms controlling pyelonephritis-associated pilus (pap) and type 1 fimbria (fim) expression in Escherichia coli.
  • To elucidate the role of phase variation in fimbrial adhesin regulation.
  • To discuss the physiological significance of these regulatory systems.

Main Methods:

  • Analysis of nucleoprotein complex formation regulating pap gene transcription.
  • Investigation of Dam methylation site protection in phase variation.
  • Examination of site-specific DNA inversion controlling fim gene expression.

Main Results:

  • Pap phase variation involves alternative nucleoprotein complexes that protect Dam methylation sites.
  • Fim phase variation is mediated by the inversion of a DNA element containing a promoter.
  • Both systems exhibit regulation in response to environmental conditions and share common regulatory features.

Conclusions:

  • Escherichia coli employs distinct molecular mechanisms (nucleoprotein complexes vs. DNA inversion) for regulating pap and fim fimbrial adhesin expression.
  • Phase variation in both systems allows adaptation to environmental conditions.
  • These regulatory strategies likely evolved to serve similar functional purposes in pathogenesis.

More Related Videos

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System11:19

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Published on: August 21, 2016

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series07:59

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Published on: May 10, 2020

Related Concept Videos

Cytoskeletal Proteins in Bacteria01:29

Cytoskeletal Proteins in Bacteria

Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
Generation of Straight or Branched Actin Filaments01:14

Generation of Straight or Branched Actin Filaments

The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Fimbriae, Pili, and Axial Filaments01:28

Fimbriae, Pili, and Axial Filaments

Fimbriae and pili are specialized bacterial surface structures that play pivotal roles in adhesion, genetic exchange, and motility. Composed primarily of pilin protein, these hairlike appendages are crucial for bacterial survival and pathogenicity in various environments.Fimbriae: Adhesion and PathogenicityFimbriae are fine, filamentous structures measuring 2–10 nanometers in diameter and are densely distributed on the bacterial cell surface. They facilitate bacterial adhesion to abiotic...
Gene Regulation in Microbial Communities: Quorum Sensing01:28

Gene Regulation in Microbial Communities: Quorum Sensing

Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
Stringent Response in E. coli01:23

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...