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Live-Cell Forward Genetic Approach to Identify and Isolate Developmental Mutants in Chlamydia trachomatis
Published on: June 10, 2020
Disulfide bonding within components of the Chlamydia type III secretion apparatus correlates with development
H J Betts-Hampikian1, K A Fields
1Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
Journal of Bacteriology
|October 18, 2011
Summary
Chlamydia
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Cell Biology
Background:
- Chlamydia spp. have a biphasic developmental cycle involving elementary bodies (EBs) and reticulate bodies (RBs).
- EB outer envelopes rely on disulfide bonds for rigidity, which are reduced in RBs for growth.
- This redox status links to the chlamydial developmental cycle.
Purpose of the Study:
- To investigate the role of disulfide bonding in the Chlamydia type III secretion system (T3SS).
- To examine T3SS structural components with high cysteine content.
- To link T3SS redox status to the bacterial developmental cycle.
Main Methods:
- Nonreducing SDS-PAGE was used to analyze protein complexes.
- Proteins from different developmental stages (EB, RB, and during conversion) were examined.
- Focus was on T3SS apparatus proteins like CdsF, CdsD, and CdsC.
Main Results:
- EB-localized T3SS proteins (CdsF, CdsD, CdsC) form disulfide-bonded higher-order complexes.
- Disulfide bonding in these proteins, especially CdsF, shifts during differentiation.
- These bonds are reduced in RBs and reoxidized during EB conversion.
- CdsF showed the most significant alterations in disulfide bonding patterns.
Conclusions:
- The redox status of specific T3SS apparatus proteins is closely tied to the Chlamydia developmental cycle.
- Disulfide bonding in T3SS components represents a novel regulatory mechanism.
- These findings offer new insights into the functional alterations within the chlamydial envelope proteins.
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