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Treponema phagedenis has at least two proteins residing together on its periplasmic flagella
Abstract:
Treponema phagedenis is an anaerobic, motile spirochete with several periplasmic flagella (PFs) at each cell end. This study provides the first genetic evidence that multiple protein species are associated with the PFs. In addition, these proteins were found to reside together on a given PF. Nonmotile mutants which lacked the PFs were isolated, and spontaneous revertants to motility regained the PFs. These results suggest that the PFs are involved in the motility of T. phagedenis. Isolated PFs had two major protein bands with molecular weights of 33,000 and 39,800, as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Western blots with monoclonal and polyclonal antibodies indicated that both proteins were absent in the PF mutants but present in the revertants. Immunoelectron microscopy revealed that the 39,800-molecular-weight protein was distributed along the entire PF. Immunoprecipitation analysis suggested that the 39,800- and 33,000-molecular-weight proteins were closely associated in situ.
Insights
Treponema phagedenis periplasmic flagella (PFs) contain multiple proteins, including two major species. These PFs are essential for the motility of this anaerobic spirochete.
Area of Science:
- Microbiology
- Bacteriology
- Cell Biology
Background:
- Treponema phagedenis is an anaerobic, motile spirochete.
- Periplasmic flagella (PFs) are located at each cell end in T. phagedenis.
Purpose of the Study:
- To investigate the protein composition of T. phagedenis PFs.
- To determine the role of PFs in the motility of T. phagedenis.
Main Methods:
- Isolation of nonmotile mutants lacking PFs and their spontaneous revertants.
- Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to analyze protein components.
- Western blotting using specific antibodies to detect proteins.
- Immunoelectron microscopy and immunoprecipitation to study protein localization and association.
Main Results:
- Genetic evidence confirmed multiple protein species associated with PFs.
- SDS-PAGE revealed two major protein bands at 33,000 and 39,800 molecular weight.
- Mutants lacking PFs were nonmotile, while revertants regained motility and PFs.
- Immunoelectron microscopy showed the 39,800 MW protein distributed along the PF.
- Immunoprecipitation suggested close association between the 39,800 and 33,000 MW proteins.
Conclusions:
- Periplasmic flagella (PFs) of T. phagedenis are composed of multiple proteins, including two major species.
- The PFs are directly involved in the motility of T. phagedenis.