title: Inhibition of gene expression and growth of multidrug-resistant Acinetobacter baumannii by antisense peptide nucleic acids.
abstract: Acinetobacter baumannii causes common and severe community- and hospital-acquired infections. The increasing emergence of multidrug-resistant (MDR) and pan-drug resistant A. baumannii has limited the therapeutic options, highlighting the need for new therapeutic strategies. The goal of this study was to investigate whether antisense peptide nucleic acids (PNAs) could mediate gene-specific inhibition effects in MDR A. baumannii. We described a screening strategy based on computational prediction and dot hybridization for identifying potential inhibitory PNAs, and evaluated the in vitro growth inhibition potency of two PNAs conjugated to the (KFF)3K peptide (pPNA1 and pPNA2), both of which targeted the growth essential gene gyrA of A. baumannii. Both pPNAs showed strong inhibition effects on bacterial growth and gyrA mRNA expression in a dose-dependent manner. The lowest inhibitory and bactericidal concentration were 5 and 10 μM, respectively. Combination of the two pPNAs showed superimposed effect other than synergistic effect. Control PNAs without (KFF)3K peptide conjugation or with mismatched antisense sequence had no inhibition effects on bacterial growth or mRNA expression. Our study suggests that anti-gyrA pPNAs can efficiently inhibit gene expression and bacterial growth, and has the potential as a new therapeutic option for MDR A. baumannii.
authors.affiliation: Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, People's Republic of China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Wang
authors.forename: Yunyan
authors.initials: Y
authors.lastname: He
authors.forename: Yun
authors.initials: Y
authors.lastname: Xia
authors.forename: Lipeng
authors.initials: L
authors.lastname: Wang
authors.forename: Shumei
authors.initials: S
authors.lastname: Liang
mesh_terms: D040981:Acinetobacter baumannii / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D001483:Base Sequence; D019295:Computational Biology; D027081:DNA Gyrase / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D015151:Immunoblotting; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000378:metabolism; D020135:Peptide Nucleic Acids / Q000378:metabolism / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D016376:Oligonucleotides, Antisense; D020135:Peptide Nucleic Acids; D027081:DNA Gyrase
references.citation: Curr Opin Struct Biol. 2006 Jun;16(3):270-8
references.pmid: 16713706
references.citation: Int J Antimicrob Agents. 2012 Feb;39(2):105-14
references.pmid: 22113193
references.citation: Clin Microbiol Rev. 2008 Jul;21(3):538-82
references.pmid: 18625687
references.citation: Antimicrob Agents Chemother. 2007 Mar;51(3):805-11
references.pmid: 17158940
references.citation: Microb Cell Fact. 2007 Aug 10;6:24
references.pmid: 17692125
references.citation: Mol Ther. 2007 Aug;15(8):1537-42
references.pmid: 17534267
references.citation: Appl Microbiol Biotechnol. 2010 Mar;86(2):397-402
references.pmid: 20135118
references.citation: Adv Genet. 2006;56:1-51
references.pmid: 16735154
references.citation: Antimicrob Agents Chemother. 2005 Aug;49(8):3203-7
references.pmid: 16048926
references.citation: Nat Biotechnol. 2001 Apr;19(4):360-4
references.pmid: 11283595
references.citation: Appl Microbiol Biotechnol. 2009 Oct;84(6):1161-8
references.pmid: 19578844
references.citation: Mol Ther. 2004 Oct;10(4):652-9
references.pmid: 15451449
references.citation: J Pept Sci. 2007 Apr;13(4):220-6
references.pmid: 17266023
references.citation: Antimicrob Agents Chemother. 1996 Aug;40(8):1801-5
references.pmid: 8843284
references.citation: Nucleic Acids Res. 2003 Jul 1;31(13):3406-15
references.pmid: 12824337
references.citation: J Mol Microbiol Biotechnol. 2005;9(2):101-9
references.pmid: 16319499
references.citation: Oligonucleotides. 2003;13(6):427-33
references.pmid: 15025910
references.citation: Proc Natl Acad Sci U S A. 1998 Mar 3;95(5):2073-6
references.pmid: 9482840