title: Impact of different cell penetrating peptides on the efficacy of antisense therapeutics for targeting intracellular pathogens.
abstract: There is a pressing need for novel and innovative therapeutic strategies to address infections caused by intracellular pathogens. Peptide nucleic acids (PNAs) present a novel method to target intracellular pathogens due to their unique mechanism of action and their ability to be conjugated to cell penetrating peptides (CPP) to overcome challenging delivery barriers. In this study, we targeted the RNA polymerase α subunit (rpoA) using a PNA that was covalently conjugated to five different CPPs. Changing the conjugated CPP resulted in a pronounced improvement in the antibacterial activity observed against Listeria monocytogenes in vitro, in cell culture, and in a Caenorhabditis elegans (C. elegans) infection model. Additionally, a time-kill assay revealed three conjugated CPPs rapidly kill Listeria within 20 minutes without disrupting the bacterial cell membrane. Moreover, rpoA gene silencing resulted in suppression of its message as well as reduced expression of other critical virulence genes (Listeriolysin O, and two phospholipases plcA and plcB) in a concentration-dependent manner. Furthermore, PNA-inhibition of bacterial protein synthesis was selective and did not adversely affect mitochondrial protein synthesis. This study provides a foundation for improving and developing PNAs conjugated to CPPs to better target intracellular pathogens.
authors: Department of Comparative Pathobiology, College of Veterinary Medicine. Purdue University, West Lafayette, Indiana, USA, 47907.|Department of Animal Hygiene and Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
authors: Mostafa F N
authors: MF
authors: Abushahba
authors: Department of Comparative Pathobiology, College of Veterinary Medicine. Purdue University, West Lafayette, Indiana, USA, 47907.
authors: Haroon
authors: H
authors: Mohammad
authors: Department of Comparative Pathobiology, College of Veterinary Medicine. Purdue University, West Lafayette, Indiana, USA, 47907.
authors: Shankar
authors: S
authors: Thangamani
authors: Department of Animal Hygiene and Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
authors: Asmaa A A
authors: AA
authors: Hussein
authors: Department of Comparative Pathobiology, College of Veterinary Medicine. Purdue University, West Lafayette, Indiana, USA, 47907.
authors: Mohamed N
authors: MN
authors: Seleem
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D017173:Caenorhabditis elegans / Q000187:drug effects / Q000382:microbiology*; D057846:Cell-Penetrating Peptides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000378:metabolism*; D008089:Listeria monocytogenes / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D016376:Oligonucleotides, Antisense / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D020135:Peptide Nucleic Acids / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D014774:Virulence / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D057846:Cell-Penetrating Peptides; D016376:Oligonucleotides, Antisense; D020135:Peptide Nucleic Acids; D012321:DNA-Directed RNA Polymerases; C113275:RNA polymerase alpha subunit