Related Experiment Video

Updated: Mar 6, 2026

Author Spotlight: Advancing Research in Microbial Autoaggregation Using Imaging Flow Cytometry
05:19

Author Spotlight: Advancing Research in Microbial Autoaggregation Using Imaging Flow Cytometry

Published on: September 29, 2023

1.3K

Cronobacter sakazakii ATCC 29544 Autoaggregation Requires FliC Flagellation, Not Motility

Jennifer L Hoeflinger1, Michael J Miller1

  • 1Department of Food Science and Human Nutrition, University of Illinois at Urbana Champaign Urbana, IL, USA.

Frontiers in Microbiology
|March 16, 2017
PubMed

Insights

Cronobacter sakazakii autoaggregation is mediated by flagella, specifically the FliC protein. This bacterial cell clumping mechanism, observed via electron microscopy, may play a role in pathogenesis.

Area of Science:

  • Microbiology
  • Pathogen Research
  • Bacterial Pathogenesis

Background:

  • Cronobacter sakazakii is an opportunistic pathogen causing severe infections in vulnerable populations.
  • The pathogenesis mechanisms of C. sakazakii, particularly in healthy individuals, remain largely unknown.
  • Bacterial autoaggregation is a potential virulence factor that requires further investigation.

Purpose of the Study:

  • To characterize the autoaggregation mechanisms of Cronobacter sakazakii ATCC 29544 (CS29544).
  • To determine the role of flagella in CS29544 autoaggregation.
  • To elucidate the molecular interactions involved in C. sakazakii autoaggregation.

Main Methods:

  • Generation and analysis of nonautoaggregating clonal variants.
  • Construction of gene knockouts (ΔflhA, ΔfliG, ΔfliC, ΔmotAB) and complementation studies (ΔfliC/cfliC).
  • Transmission electron microscopy (TEM) for visualizing cell interactions and in silico analysis of protein interactions.

Main Results:

  • Autoaggregation in CS29544 occurred rapidly (within 30 min) reaching up to 70% aggregation.
  • Structural flagellar knockouts (ΔflhA, ΔfliG, ΔfliC) abolished autoaggregation, while a functional knockout (ΔmotAB) did not.
  • Complementation with FliC restored autoaggregation, and TEM revealed filament supercoils tethering cells via FliC hydrophobic interactions.

Conclusions:

  • Structurally intact flagella, particularly the FliC protein, are essential for Cronobacter sakazakii autoaggregation.
  • Autoaggregation is mediated by direct interactions between FliC flagellin proteins of neighboring cells.
  • Flagella-mediated autoaggregation may contribute to C. sakazakii pathogenesis, warranting further investigation.
Keywords:
Cronobacter sakazakiiFliCautoaggregationflagellaprotein-protein interactions

More Related Videos

Engineering Adherent Bacteria by Creating a Single Synthetic Curli Operon15:28

Engineering Adherent Bacteria by Creating a Single Synthetic Curli Operon

Published on: November 16, 2012

15.1K
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

8.7K

Related Concept Videos

Flagella and Motility in Bacteria01:18

Flagella and Motility in Bacteria

Flagella are specialized, thread-like structures that extend from a bacteria's cell envelope. They play a crucial role in motility and chemotaxis. Their structural organization and functioning exemplify sophisticated biological engineering, enabling bacterial survival and adaptability in diverse environments.Structure of the FlagellumA bacterial flagellum consists of three key components: the filament, the hook, and basal body. The filament, a long, helical structure composed of repeating...
4.3K
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...
2.5K
Mechanism of Filopodia Formation01:39

Mechanism of Filopodia Formation

Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
3.3K
Intracellular Movement of Viruses and Bacteria01:10

Intracellular Movement of Viruses and Bacteria

Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.7K
Conjugation01:19

Conjugation

Conjugation is a form of horizontal gene transfer that primarily occurs in bacteria and some archaea, promoting genetic diversity and adaptation. Bacteria can acquire resistance genes through conjugative plasmids, allowing them to survive antibiotic treatments that would otherwise be lethal. This process involves direct contact between cells through specialized structures such as the sex pilus and is mediated by conjugative plasmids, including the F (fertility) factor.Conjugation requires...
2.6K
Rab Cascades01:25

Rab Cascades

Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
3.7K