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Live-Cell Forward Genetic Approach to Identify and Isolate Developmental Mutants in Chlamydia trachomatis
Published on: June 10, 2020
Chlamydia trachomatis outer membrane complex protein B (OmcB) is processed by the protease CPAF.
Shuping Hou1, Lei Lei, Zhangsheng Yang
1Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
Journal of Bacteriology
|December 11, 2012
Summary
Chlamydia trachomatis serine protease CPAF processes OmcB protein inside host cells. Inhibiting CPAF blocks OmcB processing, reducing infectious organism recovery, revealing CPAF
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Molecular Biology
Background:
- Chlamydia trachomatis infection involves complex protein processing.
- Outer membrane complex protein B (OmcB) was previously observed to be partially processed.
- The mechanism and timing of OmcB processing remained unclear.
Purpose of the Study:
- To confirm OmcB processing occurs within live Chlamydia-infected cells.
- To identify the specific factor responsible for OmcB processing.
- To investigate the functional role of OmcB processing in chlamydial infection.
Main Methods:
- Infection of host cells with Chlamydia trachomatis.
- Analysis of OmcB processing in cell lysates and live cells.
- Cell-free assays using purified CPAF and inhibitory peptides.
- Depletion of CPAF using specific antibodies.
- Quantification of infectious organism recovery.
Main Results:
- OmcB processing was confirmed to occur inside live Chlamydia-infected cells.
- Active Chlamydia Protease/Inhibitor (CPAF) was identified as necessary and sufficient for OmcB processing.
- Inhibition of CPAF activity blocked OmcB processing in vitro and in vivo.
- Blocking CPAF activity reduced the recovery of infectious Chlamydia organisms.
Conclusions:
- OmcB is a novel, authentic target of the Chlamydia trachomatis serine protease CPAF.
- CPAF-mediated processing of OmcB occurs within the periplasm during infection.
- Understanding this interaction is crucial for elucidating CPAF's role in chlamydial biology and pathogenesis.
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