Related Experiment Video

Updated: Jul 30, 2026

Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins
10:47

Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins

Published on: July 1, 2011

Heparin-binding outer membrane protein of chlamydiae

R S Stephens1, K Koshiyama, E Lewis

  • 1Division of Infectious Diseases, School of Public Health, 235 Earl Warren Hall, University of California, Berkeley, CA 94720, USA. rss@uclink4.berkeley.edu

Molecular Microbiology
|May 22, 2001
PubMed

Insights

Chlamydia

Area of Science:

  • Microbiology
  • Cell Biology
  • Infectious Diseases

Background:

  • Chlamydia are obligate intracellular pathogens crucial for understanding host-pathogen interactions.
  • Chlamydial invasion of eukaryotic cells is a key aspect of their lifecycle.
  • Heparan sulfate and heparin binding are implicated in Chlamydia's entry mechanism.

Purpose of the Study:

  • To identify Chlamydia outer membrane proteins responsible for heparin binding.
  • To investigate the role of heparin binding in the invasion of mammalian host cells.

Main Methods:

  • Screening Chlamydia outer membrane proteins for heparin-binding activity.
  • Mapping the heparin-binding region of the identified protein.
  • Synthesizing a peptide from the identified region to confirm heparin binding.
  • Confirming surface localization of the protein on elementary bodies (EB) using specific antibodies and cross-linking techniques.

Main Results:

  • The 60,000 molecular weight cysteine-rich outer membrane complex protein, OmcB, was identified as a heparin-binding protein.
  • A specific region within OmcB was mapped for heparin-binding capacity.
  • A synthetic 20-mer peptide from this region demonstrated specific binding to heparin.
  • Monospecific antisera confirmed OmcB's surface localization on EB, further supported by heparin-binding peptide cross-linking.

Conclusions:

  • OmcB is a surface-exposed outer membrane protein of Chlamydia that binds heparin.
  • This heparin-binding ability of OmcB likely contributes to Chlamydia's invasion of mammalian host cells.
  • Further research into OmcB could reveal novel therapeutic targets for Chlamydia infections.

More Related Videos

Using Fluorescent Proteins to Visualize and Quantitate Chlamydia Vacuole Growth Dynamics in Living Cells07:42

Using Fluorescent Proteins to Visualize and Quantitate Chlamydia Vacuole Growth Dynamics in Living Cells

Published on: October 13, 2015

Cell-Free Scaled Production and Adjuvant Addition to a Recombinant Major Outer Membrane Protein from Chlamydia muridarum for Vaccine Development12:53

Cell-Free Scaled Production and Adjuvant Addition to a Recombinant Major Outer Membrane Protein from Chlamydia muridarum for Vaccine Development

Published on: March 16, 2022

Related Concept Videos

Molecular Chaperones and Protein Folding03:00

Molecular Chaperones and Protein Folding

The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...
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...
Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
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...
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...
Bacterial Phylum Chlamydiae01:29

Bacterial Phylum Chlamydiae

The phylum Chlamydiae or Chlamydiota is composed of a single order, Chlamydiales. This phylum consists entirely of obligate intracellular parasites that infect eukaryotic hosts. While human pathogens within this group have been studied extensively, the phylum encompasses many species capable of interacting with various eukaryotic organisms. Members of Chlamydiae are typically small cocci, approximately 0.5 μm in diameter, and exhibit a distinctive developmental cycle. As is characteristic of...