Related Experiment Video

Updated: May 16, 2026

Opsono-Adherence Assay to Evaluate Functional Antibodies in Vaccine Development Against Bacillus anthracis and Other Encapsulated Pathogens
13:47

Opsono-Adherence Assay to Evaluate Functional Antibodies in Vaccine Development Against Bacillus anthracis and Other Encapsulated Pathogens

Published on: May 19, 2020

EPS-I polysaccharide protects Mycoplasma pulmonis from phagocytosis

Brandon M Shaw1, James M Daubenspeck, Warren L Simmons

  • 1Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA.

FEMS Microbiology Letters
|November 30, 2012
PubMed

Insights

Mycoplasma pulmonis uses EPS-I polysaccharide to evade immune cells. Mutants lacking this polysaccharide are more vulnerable to alveolar macrophages, revealing a new mechanism of mycoplasma pathogenesis.

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Mycoplasma pulmonis is a common cause of chronic respiratory infections in mice.
  • Alveolar macrophages are key immune cells in lung defense but inefficiently kill M. pulmonis.
  • The role of mycoplasmal polysaccharides in pathogenesis is poorly understood.

Discussion:

  • This study investigates the role of the EPS-I polysaccharide in M. pulmonis immune evasion.
  • EPS-I deficient mutants showed increased susceptibility to alveolar macrophage binding and killing.
  • This suggests that EPS-I is an antiphagocytic factor contributing to M. pulmonis survival.

Key Insights:

  • Mycoplasma pulmonis utilizes the EPS-I polysaccharide as a mechanism to evade host immune responses.
  • The absence of EPS-I significantly enhances the phagocytosis and killing of M. pulmonis by alveolar macrophages.
  • This highlights the critical role of bacterial polysaccharides in host-pathogen interactions.

Outlook:

  • Further research into EPS-I could reveal new therapeutic targets for M. pulmonis infections.
  • Understanding polysaccharide-mediated immune evasion is crucial for combating chronic microbial persistence.
  • Investigating other potential polysaccharide virulence factors in mycoplasmas is warranted.

More Related Videos

Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction05:31

Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction

Published on: May 28, 2012

Antigen-Capture Enzyme-Linked Immunosorbent Assay for Specific Detection of Mycoplasma pneumoniae06:04

Antigen-Capture Enzyme-Linked Immunosorbent Assay for Specific Detection of Mycoplasma pneumoniae

Published on: February 24, 2023

Related Concept Videos

Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
Bacterial Phylum Tenericutes01:24

Bacterial Phylum Tenericutes

The phylum Tenericutes, which includes the single class Mollicutes, comprises bacteria that lack cell walls. The term "Mollicutes" derives from the Latin word mollis, meaning "soft." These organisms are among the smallest known and are commonly referred to as mycoplasmas due to the prominence of the genus Mycoplasma, which includes well-known human pathogens. Despite their inability to stain gram-positively (a result of their lack of cell walls), mycoplasmas are phylogenetically related to the...
Atypical Pneumonia01:14

Atypical Pneumonia

Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Outer Layers of the Cell Envelope01:18

Outer Layers of the Cell Envelope

The outermost layers of prokaryotic cells play a critical role in their survival, virulence, and interaction with the environment. These layers, often composed of polysaccharides, polypeptides, or proteins, form protective and adhesive structures that vary in organization and function.Capsules and Slime LayersCapsules are highly organized, tightly bound layers that firmly attach to the bacterial cell wall. Capsules are usually made of polysaccharides, though some are made of polypeptides. These...
Formation of Lipopolysaccharides01:19

Formation of Lipopolysaccharides

Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin, triggering...