Kolano Lisa, Knappe Daniel, Berg Angela, Berg Thorsten, Hoffmann Ralf
Institute of Bioanalytical Chemistry, Faculty of Chemistry and Mineralogy, 04103, Leipzig, Germany.
Center for Biotechnology and Biomedicine, Universität Leipzig, 04103, Leipzig, Germany.
Chembiochem. 2022 Mar 4;23(5):e202100609. doi: 10.1002/cbic.202100609. Epub 2022 Jan 12.
Proline-rich antimicrobial peptides (PrAMPs) are promising candidates for the treatment of infections caused by high-priority human pathogens. Their mode of action consists of (I) passive diffusion across the outer membrane, (II) active transport through the inner membrane, and (III) inhibition of protein biosynthesis by blocking the exit tunnel of the 70S ribosome. We tested whether in vitro data on ribosomal binding and bacterial uptake could predict the antibacterial activity of PrAMPs against Gram-negative and Gram-positive bacteria. Ribosomal binding and bacterial uptake rates were measured for 47 derivatives of PrAMP Onc112 and compared to the minimal inhibitory concentrations (MIC) of each peptide. Ribosomal binding was evaluated for ribosome extracts from four Gram-negative bacteria. Bacterial uptake was assessed by quantifying each peptide in the supernatants of bacterial cultures. Oncocin analogues with a higher net positive charge appeared to be more active, although their ribosome binding and uptake rates were not necessarily better than for Onc112. The data suggest a complex mode of action influenced by further factors improving or reducing the antibacterial activity, including diffusion through membranes, transport mechanism, secondary targets, off-target binding, intracellular distribution, and membrane effects. Relying only on in vitro binding and uptake data may not be sufficient for the rational development of more active analogues.
富含脯氨酸的抗菌肽（PrAMPs）是治疗由高优先级人类病原体引起的感染的有前景的候选药物。它们的作用方式包括：（I）通过外膜的被动扩散；（II）通过内膜的主动转运；以及（III）通过阻断70S核糖体的出口通道来抑制蛋白质生物合成。我们测试了关于核糖体结合和细菌摄取的体外数据是否能够预测PrAMPs对革兰氏阴性菌和革兰氏阳性菌的抗菌活性。对PrAMP Onc112的47种衍生物的核糖体结合和细菌摄取率进行了测量，并与每种肽的最小抑菌浓度（MIC）进行了比较。对来自四种革兰氏阴性菌的核糖体提取物进行了核糖体结合评估。通过对细菌培养上清液中的每种肽进行定量来评估细菌摄取。净正电荷较高的癌蛋白类似物似乎更具活性，尽管它们的核糖体结合和摄取率不一定比Onc112更好。数据表明存在一种受其他因素影响的复杂作用方式，这些因素会增强或降低抗菌活性，包括通过膜的扩散、转运机制、次要靶点、脱靶结合、细胞内分布和膜效应。仅依靠体外结合和摄取数据可能不足以合理开发更具活性的类似物。
