Related Experiment Video

Updated: Oct 12, 2025

The C. elegans Intestine As a Model for Intercellular Lumen Morphogenesis and In Vivo Polarized Membrane Biogenesis at the Single-cell Level: Labeling by Antibody Staining, RNAi Loss-of-function Analy
12:15

The C. elegans Intestine As a Model for Intercellular Lumen Morphogenesis and In Vivo Polarized Membrane Biogenesis at the Single-cell Level: Labeling by Antibody Staining, RNAi Loss-of-function Analy

Published on: October 3, 2017

13.7K

RadA, a MSCRAMM Adhesin of the Dominant Symbiote Ruminococcus gnavus E1, Binds Human Immunoglobulins and Intestinal

Marc Maresca1, Radia Alatou2, Ange Pujol1

  • 1Aix Marseille University, CNRS, Centrale Marseille, ISM2, IM2B, 13007 Marseille, France.

Biomolecules
|November 27, 2021
PubMed

Insights

Ruminococcus gnavus E1 expresses RadA, a gut-colonizing adhesin, which binds human immunoglobulins and mucins. This adhesin targets specific galactose and N-acetyl-galactosamine motifs on host cells.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Gastroenterology

Background:

  • Bacterial adhesion to the digestive mucosa is crucial for gut colonization.
  • Ruminococcus gnavus is a gut bacterium whose adhesion mechanisms require further elucidation.

Purpose of the Study:

  • To investigate the role of the RadA adhesin from Ruminococcus gnavus E1 in gut mucosal adhesion.
  • To identify the specific molecular targets of the RadA adhesin.

Main Methods:

  • Analysis of radA gene expression during gut colonization.
  • Characterization of the RadA N-terminal region's binding properties using various substrates.
  • Competition assays with lectins and monosaccharides to identify binding motifs.

Main Results:

  • Ruminococcus gnavus E1 expresses the RadA adhesin specifically during gut colonization.
  • The RadA N-terminal region binds human immunoglobulins (IgA, IgG) and intestinal mucins.
  • RadA recognizes the protein backbone of IgG and glycan structures of mucins, specifically Galactose and N-Acetyl-Galactosamine motifs.

Conclusions:

  • RadA is an MSCRAMM family adhesin critical for Ruminococcus gnavus E1 gut persistence.
  • RadA mediates adhesion through interactions with host immunoglobulins and mucins via specific glycan recognition.
Keywords:
Caco-2HT-29-16ERuminococcus gnavusadhesinbacterial Ig-like domaincollagenmucinmucussolid phase assay

More Related Videos

In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells05:57

In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells

Published on: May 16, 2011

26.1K
Biomimetic Materials to Characterize Bacteria-host Interactions12:22

Biomimetic Materials to Characterize Bacteria-host Interactions

Published on: November 16, 2015

9.6K

Related Concept Videos

Adherens Junctions01:24

Adherens Junctions

Strong contact points between adjacent cells anchor them to each other, forming tissues. Such anchoring junctions are of two types –  adherens junctions and desmosomes. Adherens junctions are abundant in tissues such as  epithelium and endothelium, forming a continuous zone of adhesion called the adhesion belt. In other tissues, such as  heart muscle, they appear as clusters, linking the cells to produce coordinated heart muscle contraction.
Adherens Junctions are Dynamic
5.2K
Immunoglobulin-like Cell Adhesion Molecules01:31

Immunoglobulin-like Cell Adhesion Molecules

Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
3.5K
Rab Proteins01:14

Rab Proteins

Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
4.3K
Integrins01:10

Integrins

Animal and protozoan cells do not have cell walls to help maintain shape and provide structural stability. Instead, these eukaryotic cells secrete a sticky mass of carbohydrates and proteins into the spaces between adjacent cells. This network of proteins and molecules is called an extracellular matrix or ECM.
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
4.3K
Cell Adhesion Molecules - Types and Functions01:20

Cell Adhesion Molecules - Types and Functions

Cell adhesion molecules (CAMs) are pivotal to multicellularity and the coordinated functioning of tissues and organ systems. They enable physical interactions between cells and provide mechanical strength to tissues. They also function as receptors for signal transmission across the plasma membrane. The CAMs are broadly classified into four families - integrins, cadherins, selectins, and immunoglobulin-like CAMs (IgCAMs).
CAM Families
The Integrin family of proteins is primarily  involved...
7.8K
Transcytosis of IgG01:15

Transcytosis of IgG

Transcytosis is the process in which molecules are internalized by endocytosis, transported across the cell, and released through exocytosis from the opposite end of the cell. Molecules such as insulin, immunoglobulins, and certain nutrients are transferred through the recycling endosomes by recycling and transcytosis.
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
3.0K