ABSTRACTThe SpoVG protein ofBorrelia burgdorferi, the Lyme disease spirochete, binds to specific sites of DNA and RNA. The bacterium regulates transcription ofspoVGduring the natural tick-mammal infectious cycle and in response to some changes in culture conditions. Bacterial levels ofspoVGmRNA and SpoVG protein did not necessarily correlate, suggesting that posttranscriptional mechanisms also control protein levels. Consistent with this, SpoVG binds to its own mRNA, adjacent to the ribosome-binding site. SpoVG also binds to two DNA sites in theglpFKDoperon and to two RNA sites inglpFKDmRNA; that operon encodes genes necessary for glycerol catabolism and is important for colonization in ticks. In addition, spirochetes engineered to dysregulatespoVGexhibited physiological alterations.IMPORTANCEB. burgdorferipersists in nature by cycling between ticks and vertebrates. Little is known about how the bacterium senses and adapts to each niche of the cycle. The present studies indicate thatB. burgdorfericontrols production of SpoVG and that this protein binds to specific sites of DNA and RNA in the genome and transcriptome, respectively. Altered expression ofspoVGexerts effects on bacterial replication and other aspects of the spirochete's physiology.
Structural and biochemical analyses of DNA and RNA binding by a bifunctional homing endonuclease and group I intron splicing factor
