Related Experiment Video
Updated: Jul 27, 2025
07:59
Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series
Published on: May 10, 2020
7.8K
Flagellar-based motility accelerates IgA-mediated agglutination of
Samantha K Lindberg1,2, Graham G Willsey2, Nicholas J Mantis1,2
1Department of Biomedical Sciences, University at Albany School of Public Health, Albany, NY, United States.
Frontiers in Immunology
|June 5, 2023
Summary
Secretory IgA (SIgA) uses a novel "snow globe" assay to show bacterial motility is key for agglutination, preventing Salmonella Typhimurium (STm) infection. This process helps clear pathogens from the gut.
Area of Science:
- Immunology
- Microbiology
- Bacterial Pathogenesis
Background:
- Secretory IgA (SIgA) is crucial for intestinal immunity, protecting the gut epithelium from pathogens like Salmonella enterica serovar Typhimurium (STm).
- SIgA mediates immune exclusion by aggregating bacteria, which form biofilm-like structures at high densities.
- The mechanism by which SIgA induces this transition from motile to sessile states in STm is not fully understood.
Purpose of the Study:
- To develop and validate a novel methodology, the "snow globe" assay, for real-time imaging and quantification of STm agglutination by SIgA.
- To investigate the factors influencing SIgA-mediated STm agglutination, including antibody characteristics and bacterial properties.
Main Methods:
- Development and application of the "snow globe" assay for live imaging of STm agglutination.
- Dose-response, antigen-specificity, and isotype-influence studies of SIgA-mediated agglutination.
- Investigation of bacterial motility and cyclic-di-GMP metabolizing enzymes in the agglutination process.
Main Results:
- SIgA-mediated STm agglutination is dose-dependent, antigen-specific, and influenced by antibody isotype.
- Flagellar-based motility is essential for the rapid onset of STm agglutination, even at high cell densities.
- Bacterial motility and cell-cell collisions are dynamic factors in IgA-mediated agglutination.
Conclusions:
- The "snow globe" assay is an effective platform for studying SIgA-mediated bacterial agglutination.
- Bacterial motility plays a critical role in the transition of STm from a motile to an avirulent, agglutinated state.
- Further research using this assay can elucidate the molecular and genetic factors governing SIgA-STm interactions.
Related Concept Videos
01:18Flagella and Motility in Bacteria
77
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...
77
01:28Fimbriae, Pili, and Axial Filaments
63
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...
63
01:39Mechanism of Filopodia Formation
2.4K
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...
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...
2.4K
01:12Immunofluorescence Microscopy
10.7K
A fluorescence microscope uses fluorescent chromophores called fluorochromes, which can absorb energy from a light source and then emit this energy as visible light. Fluorochromes include naturally fluorescent substances (such as chlorophylls) and fluorescent stains that are added to the specimen to create contrast. Dyes such as Texas red and FITC are examples of fluorochromes. Other examples include the nucleic acid dyes 4’,6’-diamidino-2-phenylindole (DAPI), and acridine orange.
10.7K
01:10Intracellular Movement of Viruses and Bacteria
2.9K
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...
2.9K
01:13Special Staining Techniques
63
Specialized staining techniques play a vital role in microbiology by enabling the visualization of specific bacterial structures that remain undetectable with standard microscopy methods. These techniques not only enhance the structural visualization of bacterial cells but also provide critical insights into their pathogenicity and classification. Additionally, they support diagnostic and research endeavors in microbiology by identifying key bacterial features.Capsule Staining for Virulence...
63