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Isolation of Labile Multi-protein Complexes by in vivo Controlled Cellular Cross-Linking and Immuno-magnetic Affinity Chromatography
Published on: March 9, 2010
Chlamydia trachomatis polymorphic membrane protein D is an oligomeric autotransporter with a higher-order structure
Kena A Swanson1, Lacey D Taylor, Shaun D Frank
1Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South 4th St., Hamilton, MT 59840, USA.
Infection and Immunity
|November 13, 2008
Summary
Chlamydia trachomatis polymorphic membrane protein D (PmpD) forms a flower-like structure and is processed into fragments. This bacterial protein may be a key target for new chlamydia vaccines and drugs.
Area of Science:
- Microbiology
- Immunology
- Vaccine Development
Background:
- Chlamydia trachomatis causes sexually transmitted infections and trachoma.
- A preventative vaccine is crucial for controlling these diseases.
- Chlamydia trachomatis polymorphic membrane protein D (PmpD) is a conserved vaccine candidate targeted by neutralizing antibodies.
Purpose of the Study:
- To investigate the structure and processing of Chlamydia trachomatis polymorphic membrane protein D (PmpD).
- To explore PmpD's potential as a vaccine or drug target for chlamydial infections.
Main Methods:
- Immunoaffinity purification of native PmpD.
- Two-dimensional blue native-polyacrylamide gel electrophoresis.
- Analysis of PmpD proteolytic processing during infection.
Main Results:
- Native PmpD exists as a 23-nm flower-like oligomer.
- Oligomers comprise full-length PmpD (p155) and processed fragments (p73, p82).
- PmpD undergoes infection-dependent processing into soluble fragments (p111, p73, p30) with eukaryote-interacting motifs.
Conclusions:
- PmpD exists in two forms: a surface-associated oligomer and a soluble intracellular form.
- PmpD is a multifunctional virulence factor with potential as a novel target for chlamydial infection control.
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