Disrupting protein expression with Peptide Nucleic Acids reduces infection by obligate intracellular Rickettsia

• Published in: PloS one Vol. 10; no. 3; p. e0119283
• Main Authors: Pelc, Rebecca S, McClure, Jennifer C, Kaur, Simran J, Sears, Khandra T, Rahman, M Sayeedur, Ceraul, Shane M
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.03.2015; Public Library of Science (PLoS)
• Subjects: Acids; Animals; Bacteria; Bacterial Outer Membrane Proteins - antagonists & inhibitors; Bacterial Outer Membrane Proteins - metabolism; Bacterial Proteins - antagonists & inhibitors; Bacterial Proteins - metabolism; Blotting, Western; Cell-Penetrating Peptides - pharmacology; Cells, Cultured; Chlorocebus aethiops; Codons; Cytoplasm - metabolism; Dermacentor variabilis; Electroporation; Fibroblasts - drug effects; Fibroblasts - metabolism; Fibroblasts - microbiology; Gene expression; Gene Expression Regulation, Bacterial - drug effects; Genetic engineering; Health aspects; Historical account; Immunology; Infection; Infections; Intracellular; Kinases; Medicine; Mice; Motility; mRNA; Nucleic acids; Pediatrics; Peptide nucleic acids; Peptide Nucleic Acids - chemistry; Peptide Nucleic Acids - pharmacology; Peptides; Phosphates; Protein biosynthesis; Protein expression; Protein Processing, Post-Translational; Protein synthesis; Proteins; Researchers; Rickettsia; Rickettsia - drug effects; Rickettsia - genetics; Rickettsia - growth & development; Rickettsia - metabolism; Rickettsia conorii; Rickettsia Infections - drug therapy; Rickettsia Infections - genetics; Rickettsia Infections - microbiology; Rickettsia montanensis; RNA, Messenger - genetics; RNA, Messenger - metabolism; Studies; Sugar; Translation; Translation (Genetics); Typhus; Vero Cells; United States > US; Maryland; Baltimore Maryland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0119283

Peptide Nucleic Acids (PNAs) are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria's ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria.