کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5533330 | 1402115 | 2017 | 11 صفحه PDF | دانلود رایگان |

- SaPIs are mobilized by helper phages.
- SaPIbov1 Stl is derepressed by the type 2 dUTPase from phage ÏNM1 (DutNM1).
- Mobilization of SaPIbov1 by ÏNM1 does not require DutNM1 dUTPase activity.
- Derepression of Stl by DutNM1 is inhibited by dUTP and dUMP.
Staphylococcus aureus is an opportunistic human pathogen able to transfer virulence genes to other cells through the mobilization of S. aureus pathogenicity islands (SaPIs). SaPIs are derepressed and packaged into phage-like transducing particles by helper phages like 80α or ÏNM1. Phages 80α and ÏNM1 encode structurally distinct dUTPases, Dut80α (type 1) and DutNM1 (type 2). Both dUTPases can interact with the SaPIbov1 Stl master repressor, leading to derepression and mobilization. That two structurally distinct dUTPases bind the same repressor led us to speculate that dUTPase activity may be important to the derepression process. In type 1 dUTPases, Stl binding is inhibited by dUTP. The purpose of this study was to assess the involvement of dUTP binding and dUTPase activity in derepression by DutNM1. DutNM1 activity mutants were created and tested for dUTPase activity using a novel NMR-based assay. We found that all DutNM1 null activity mutants interacted with the SaPIbov1 Stl C-terminal domain, formed DutNM1-Stl heterodimers, and caused the release of the Pstr promoter. However, promoter release was inhibited in the presence of dUTP or dUMP. We tested two ÏNM1 mutant phages that had null enzyme activity and found that they could still mobilize SaPIbov1. These results show that only the apo form of DutNM1 is active in Stl derepression and that dUTPase activity is not necessary for the mobilization of SaPIbov1 by DutNM1.
Graphical Abstract85
Journal: Journal of Molecular Biology - Volume 429, Issue 10, 19 May 2017, Pages 1570-1580