AUTHOR=Tassinari Eleonora , Aznar Sonia , Urcola Imanol , Prieto Alejandro , Hüttener Mário , Juárez Antonio 

TITLE=The incC Sequence Is Required for R27 Plasmid Stability

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 7 - 2016

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.00629

DOI=10.3389/fmicb.2016.00629

ISSN=1664-302X

ABSTRACT=IncHI plasmids account for multiple antimicrobial resistance in Salmonella and other enterobacterial genera. These plasmids are generally very stable in their bacterial hosts. R27 is the archetype of IncHI1 plasmids. A high percentage of the R27-encoded ORFs (66.7%) do not show similarity to any known ORFs. We performed a deletion analysis of all non-essential R27 DNA sequences to search for hitherto non-identified plasmid functions that might be required for plasmid stability. We report the identification of a short DNA sequence (incC) that is essential for R27 stability. That region contains several repeats (incC repeats), belongs to one of the three-plasmid replicons (R27 FIA-like) and is targeted by the R27 E protein. Deletion of the incC sequence drastically reduces R27 stability both in E. coli and in Salmonella, the effect being more pronounced in this latter species. Interfering with incC-E protein interaction must lead to a reduced IncHI1 plasmid stability, and may represent a new approach to combat antimicrobial resistance.