Motility characteristics are altered for Rickettsia bellii transformed to overexpress a heterologous rickA gene

Jonathan D. Oliver, Nicole Y. Burkhardt, Roderick F. Felsheim, Timothy J. Kurtti, Ulrike G. Munderloh

Research output: Contribution to journalArticle

19 Scopus citations

Abstract

The rickettsial protein RickA activates host cell factors associated with the eukaryotic actin cytoskeleton and is likely involved with rickettsial host cell binding and infection and the actin-based motility of spotted fever group rickettsiae. The rickA gene sequence and protein vary substantially between Rickettsia species, as do observed motility-associated phenotypes. To help elucidate the function of RickA and determine the effects of species-specific RickA variations, we compared extracellular binding, intracellular motility, and intercellular spread phenotypes of three Rickettsia bellii variants. These included two shuttle vectortransformed R. bellii strains and the wild-type isolate from which they were derived, R. bellii RML 369C. Both plasmid shuttle vectors carried spectinomycin resistance and a GFPuv reporter; one contained Rickettsia monacensis-derived rickA, and the other lacked the rickA gene. Rickettsia bellii transformed to express R. monacensis rickA highly overexpressed this transcript in comparison to its native rickA. These rickettsiae also moved at higher velocities and followed a more curved path than the negative-control transformants. A lower proportion of R. monacensis rickA-expressing bacteria ever became motile, however, and they formed smaller plaques.

Original languageEnglish (US)
Pages (from-to)1170-1176
Number of pages7
JournalApplied and environmental microbiology
Volume80
Issue number3
DOIs
StatePublished - Feb 1 2014

Fingerprint Dive into the research topics of 'Motility characteristics are altered for Rickettsia bellii transformed to overexpress a heterologous rickA gene'. Together they form a unique fingerprint.

Cite this