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bioRxiv · 10.1101/2025.07.11.664372

Development of two compatible plasmids to assess sRNA-mediated post-transcriptional regulation in Acinetobacter baumannii

Mogre, A.·Connell, O.·White, J.·Shaibah, A.·Hokamp, K.·Hamrock, F. J.·Schauer, K.·Kroeger, C.
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Abstract

Post-transcriptional regulation can be mediated by small, regulatory RNAs in bacteria, which can act by base-pairing to a target messenger RNA. The discovery and mechanistic validation of base-pairing sRNAs in multidrug resistant Acinetobacter baumannii has been hampered by the lack of genetic tools to assess RNA-RNA interactions. Here, we created two compatible plasmids for A. baumannii, which addresses this need. The newly designed plasmids validated the known Aar sRNA-carO mRNA, and a new interaction of sRNA44 and the mRNA of the biofilm-associated protein Bap. The new plasmid system should accelerate the mechanistic characterisation of small, regulatory RNAs in A. baumannii. IMPACT STATEMENTMulti-drug resistance of pathogenic microorganisms is one of the greatest challenges for modern medicine. Carbapenem-resistant Acinetobacter baumannii are considered a highly critical organism, yet we are only beginning to understand its physiology and mechanisms of gene regulation. Post-transcriptional regulation by base-pairing, small RNAs is an understudied area, partly because of the lack of genetic tools to investigate them. In this study, we developed a 2-plasmid system to assess sRNA-mRNA interactions, which will greatly accelerate the discovery and validation of small, regulatory RNAs and their target molecules. DATA SUMMARYPlasmid sequences of pAMCK14-sRNA44 and pAMCK18-Bap have been made available in GenBank of National Center for Biotechnology Information (accession numbers PV916437 and PV916438).

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Mogre, A., Connell, O., White, J., Shaibah, A., Hokamp, K., Hamrock, F. J., Schauer, K., Kroeger, C.. 2025-07-11. Development of two compatible plasmids to assess sRNA-mediated post-transcriptional regulation in Acinetobacter baumannii. https://doi.org/10.1101/2025.07.11.664372

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