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An Electroporation Method to Transform Rickettsia spp. with a Fluorescent Protein-Expressing Shuttle Vector in Tick Cell Lines
Published on: October 11, 2022
An anomalous type IV secretion system in Rickettsia is evolutionarily conserved.
Joseph J Gillespie1, Nicole C Ammerman, Sheila M Dreher-Lesnick
1Virginia Bioinformatics Institute at Virginia Tech, Blacksburg, Virginia, United States of America. jgill@vbi.vt.edu
Plos One
|March 13, 2009
Summary
Researchers identified the Rickettsiales vir homolog (rvh) type IV secretion system (T4SS) in Rickettsia bacteria. This conserved system has an unknown role in rickettsial biology, providing a foundation for future studies.
Area of Science:
- Microbiology
- Molecular Biology
- Evolutionary Biology
Background:
- Bacterial type IV secretion systems (T4SSs) are diverse transporters involved in DNA and protein translocation.
- Rickettsia genomes reveal a reduced T4SS compared to the Agrobacterium tumefaciens archetype.
- The Rickettsia T4SS function in symbiosis/virulence and its substrates remain uncharacterized.
Purpose of the Study:
- To characterize the Rickettsia T4SS and its components.
- To investigate the evolutionary origins and potential function of the Rickettsia T4SS.
Main Methods:
- Comparative genomics analysis of Rickettsia T4SS components.
- Phylogenetic analysis of T4SS genes.
- Structural and functional information superposition.
Main Results:
- A functional Rickettsia T4SS, termed rvh T4SS, was identified, lacking only virB5 compared to the archetype.
- Duplicated genes (virB4, virB8, virB9, VirB6) suggest complex regulation or function.
- Phylogenetic analysis suggests acquisition of a vir-like locus and subsequent diversification.
Conclusions:
- The rvh T4SS is an evolutionarily conserved transporter in Rickettsia with an undetermined role.
- This study establishes a basis for future laboratory investigations of the rvh T4SS.
- The Legionella lvh T4SS is proposed as a suitable genetic model for studying related systems.
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