Frimodt-Møller Jakob, Koulouktsis Andreas, Charbon Godefroid, Otterlei Marit, Nielsen Peter E, Løbner-Olesen Anders
Department of Biology, Center for Peptide-Based Antibiotics, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen N, Denmark.
Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, NTNU, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway.
Mol Ther Nucleic Acids. 2021 Jun 24;25:444-454. doi: 10.1016/j.omtn.2021.06.009. eCollection 2021 Sep 3.
Cell-penetrating peptides (CPPs) are increasingly used for cellular drug delivery in both pro- and eukaryotic cells, and oligoarginines have attracted special attention. How arginine-rich CPPs translocate across the cell envelope, particularly for prokaryotes, is still unknown. Arginine-rich CPPs efficiently deliver antimicrobial peptide nucleic acid (PNA) to its intracellular mRNA target in bacteria. We show that resistance to PNA conjugated to an arginine-rich CPP in requires multiple genetic modifications and is specific for the CPP part and not to the PNA part. An integral part of the resistance was the constitutively activated Cpx-envelope stress response system (), which decreased the cytoplasmic membrane potential. This indicates an indirect energy-dependent uptake mechanism for antimicrobials conjugated to arginine-rich CPPs. In agreement, mutants showed low-level resistance to aminoglycosides and an arginine-rich CPP conjugated to a peptide targeting the DNA sliding clamp, i.e., similar uptake in for these antimicrobial compounds.
细胞穿透肽（CPPs）越来越多地用于原核细胞和真核细胞的细胞药物递送，其中寡聚精氨酸受到了特别关注。富含精氨酸的CPPs如何穿过细胞膜，尤其是对于原核生物而言，仍然未知。富含精氨酸的CPPs能有效地将抗菌肽核酸（PNA）递送至细菌细胞内的mRNA靶点。我们发现，对与富含精氨酸的CPPs偶联的PNA产生抗性需要多个基因修饰，并且这种抗性是针对CPP部分而非PNA部分的。抗性的一个重要组成部分是组成型激活的Cpx包膜应激反应系统，该系统降低了细胞质膜电位。这表明与富含精氨酸的CPPs偶联的抗菌药物存在间接的能量依赖性摄取机制。与此一致的是，突变体对氨基糖苷类药物以及与靶向DNA滑动夹的肽偶联的富含精氨酸的CPPs表现出低水平抗性，即这些抗菌化合物在突变体中的摄取情况类似。
