title: The H-NS protein silences the pyp regulatory network of Yersinia enterocolitica and is involved in controlling biofilm formation.
abstract: Horizontal gene transfer plays an important role in bacterial evolution. DNA acquired by horizontal gene transfer has to be incorporated into existing regulatory networks. The histone-like nucleoid structuring protein H-NS acts as a silencer of horizontally acquired genes to avoid potential damage. However, specific regulators can overcome H-NS repression, resulting in the integration of newly acquired genes into existing regulatory networks. Here, we analyzed the influence of H-NS on the transcription of the Yersinia enterocolitica hreP gene and its regulators pypA, pypB, and pypC by establishing a dominant-negative H-NS version. Using transcriptional fusions and electrophoretic mobility shift assays, we show that H-NS silences hreP, pypA, pypB, and pypC by direct interactions. While the H-NS antagonist RovA activates pypC, it has no effect on pypA and pypB. Furthermore, H-NS affects biofilm formation in Y. enterocolitica.
authors.affiliation: Westfälische Wilhelms-Universität Münster, Zentrum für Molekularbiologie der Entzündung (ZMBE), Institut für Infektiologie, Münster, Germany.
authors.forename: Inga
authors.initials: I
authors.lastname: Blädel
authors.forename: Karin
authors.initials: K
authors.lastname: Wagner
authors.forename: Anna
authors.initials: A
authors.lastname: Beck
authors.forename: Jennifer
authors.initials: J
authors.lastname: Schilling
authors.forename: M
authors.initials: M
authors.lastname: Alexander Schmidt
authors.forename: Gerhard
authors.initials: G
authors.lastname: Heusipp
mesh_terms: D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D011485:Protein Binding; D013381:Subtilisins / Q000096:biosynthesis; D015008:Yersinia enterocolitica / Q000235:genetics* / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria; C430046:HreP protein, Yersinia enterocolitica; D013381:Subtilisins