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Article Abstract
Most strains are naturally competent. Although some information is available about factors that enhance or reduce the frequency of the transformation of this bacterium, the regulatory elements and mechanisms are barely understood. In this article, we describe studies on the role of the histone-like nucleoid structuring protein, H-NS, in the regulation of the expression of genes related to natural competency and the ability to uptake foreign DNA. The expression levels of the natural transformation-related genes , , , , , , and significantly increased in a Δ derivative of A118. The complementation of the mutant with a recombinant plasmid harboring restored the expression levels of six of these genes ( remained expressed at high levels) to those of the wild-type strain. The transformation frequency of the A118 Δ strain was significantly higher than that of the wild-type. Similar, albeit not identical, there were consequences when was deleted from the hypervirulent AB5075 strain. In the AB5075 complemented strain, the reduction in gene expression in a few cases was not so pronounced that it reached wild-type levels, and the expression of was enhanced further. In conclusion, the expression of all seven transformation-related genes was enhanced after deleting in A118 and AB5075, and these modifications were accompanied by an increase in the cells' transformability. The results highlight a role of H-NS in natural competence.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8470039 | PMC |
| http://dx.doi.org/10.3390/pathogens10091083 | DOI Listing |
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