Targeted mutagenesis of intergenic regions in the Neisseria gonorrhoeae gonococcal genetic island reveals multiple regulatory mechanisms controlling type IV secretion.

ABSTRACT: Gonococci secrete chromosomal DNA into the extracellular environment using a type IV secretion system (T4SS). The secreted DNA acts in natural transformation and initiates biofilm development. Although the DNA and its effects are detectable, structural components of the T4SS are present at very low levels, suggestive of uncharacterized regulatory control. We sought to better characterize the expression and regulation of T4SS genes and found that the four operons containing T4SS genes are transcribed at very different levels. Increasing transcription of two of the operons through targeted promoter mutagenesis did not increase DNA secretion. The stability and steady-state levels of two T4SS structural proteins were affected by a homolog of tail-specific protease. An RNA switch was also ident

SUBMITTER: Ramsey ME 

PROVIDER: S-EPMC4652943 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature