A truncated AdeS kinase protein generated by ISAba1 insertion correlates with tigecycline resistance in Acinetobacter baumannii.

Over-expression of AdeABC efflux pump stimulated continuously by the mutated AdeRS two component system has been found to result in antimicrobial resistance, even tigecycline (TGC) resistance, in multidrug-resistant Acinetobacter baumannii (MRAB). Although the insertion sequence, ISAba1, contributes to one of the AdeRS mutations, the detail mechanism remains unclear. In the present study we collected 130 TGC-resistant isolates from 317 carbapenem resistant MRAB (MRAB-C) isolates, and 38 of them were characterized with ISAba1 insertion in the adeS gene.

Neurovirulent flavivirus can be attenuated in mice by incorporation of neuron-specific microRNA recognition elements into viral genome.

Engineering viruses by inserting microRNA (miRNA) recognition elements (MREs) into the 3'-untranslated region (3'-UTR) of viral RNA can efficiently restrict viral tissue tropism. We used the mosquito-borne Japanese encephalitis virus (JEV) to investigate whether endogenous neuron-specific microRNA-124 (miR-124) could be used to restrict viral neurotropism and, consequently, diminish the neurovirulence of JEV in mice. To recover a neuron-restricted JEV, we inserted 2 copies of a perfectly matched MRE specific to miR-124 into the 3'-UTR to create infectious JEV recombinant RP-124PT (rRP-124PT).

Utilizing liver-specific microRNA-122 to modulate replication of dengue virus replicon.

microRNAs (miRNAs) are endogenous non-coding RNAs that spatiotemporally modulate mRNAs in a post-transcriptional manner. The engineering of viruses by insertion of a tissue-specific miRNA recognition element (MRE) into viral mRNA can restrict viral tissue tropism. In this study we employed dengue virus (DEN) replicons to investigate whether miRNAs are able to suppress flavivirus replication through the targeting of non-polyadenylated viral mRNA.