Kazufumi NAKAI

Sequence-specific Inhibition of Microbial growth by Peptide Nucleic Acids


Akiyoshi OHASHI, Hideki HARADA, Hiroyuki IMACHI



Antisense technology which is based on Watson-Crick base pairing enables to inhibit translation by sequence-specific polynucleic acids. We applied peptide nucleic acids (PNA) as antisense polynucleic acids to restrict Escherichia coli gworth in order to confirm sequence-specific inhibition of microbial growth by antisene technology.



Antisense target sites of E.coli were as follows: acpP mRNA, mRNA binding site of 16S rRNA, and EUB338 region of 16S rRNA. The PNAs of which N terminus has cell membrane penetrating peptide were added into E.coli solutions, and the solutions were sampled several times to determine colony forming unit as the results of the PNAs' antisense effect. Cell membrane penetrating peptide and dimethyl sulfoxide (DMSO) which solves the PNAs are also checked because they were strongly predicted to inhibit E.coli growth by them alone.



Through the experiments, we firstly defined the ranges of non inhibitory concentrations of cell membrane penetrating peptide and DMSO in order to obtain accurate antisense effect of the PNAs. Then, we observed the antisense effects by PNAs targeted acpP mRNA and mRNA binding site of 16S rRNA.