Related Experiment Videos
The effect of purification on the ultrastructure and infectivity of egg-attenuated Chlamydia psittaci (6BC)
Abstract:
A procedure is described for the purification of mixed populations of the three different morphological forms of Chlamydia psittaci (6BC) from infected yolk sac membranes. Elementary bodies and small intermediate bodies are not perceptibly damaged during purification which involves homogenization of the host cells, differential centrifugation, sedimentation through 20% sucrose, and treatment with trypsin. The observation that elementary bodies undergo plasmolysis in 20% sucrose is interpreted as indicating that the cytoplasmic membrane of these particles is intact at that stage in the purification. Reticulate bodies and large intermediate bodies are damaged, to a degree, by the homogenization step. This damage takes the form of discontinuities of the outer envelope membrane, and results in the loss of the regular coccobacillary shape of these particles and in an increase in their size. Treatment with a combination of RNase and DNase was found to cause profound damage to all three morphological forms of the chlamydiae.
Insights
This study details a method for purifying Chlamydia psittaci, preserving elementary and small intermediate bodies while noting damage to larger forms. The procedure involves homogenization, centrifugation, and trypsin treatment for effective Chlamydia psittaci purification.
Area of Science:
- Microbiology
- Cell Biology
- Infectious Diseases
Background:
- Chlamydia psittaci exhibits distinct morphological forms.
- Purification methods are crucial for studying Chlamydia psittaci.
- Understanding Chlamydia psittaci morphology is key to its biology.
Purpose of the Study:
- To describe a purification procedure for Chlamydia psittaci.
- To assess the impact of purification steps on different Chlamydia psittaci forms.
- To maintain the integrity of Chlamydia psittaci elementary bodies.
Main Methods:
- Homogenization of infected yolk sac membranes.
- Differential centrifugation and 20% sucrose sedimentation.
- Trypsin treatment to purify Chlamydia psittaci populations.
Main Results:
- Elementary bodies and small intermediate bodies remained intact.
- Reticulate bodies and large intermediate bodies showed membrane damage.
- RNase and DNase treatment severely damaged all Chlamydia psittaci forms.
Conclusions:
- The described method effectively purifies Chlamydia psittaci.
- The purification process preserves key Chlamydia psittaci forms.
- Protective measures are needed for reticulate and large intermediate bodies.