Department of Biotechnology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran.
Drug Design and Bioinformatics Unit, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
Chem Biol Drug Des. 2020 Aug;96(2):801-811. doi: 10.1111/cbdd.13689. Epub 2020 Apr 19.
Caerin 4 is a family of AMPs isolated from the frog called Litoria caerulea. In silico drug designing methods and using machine learning algorithms for AMPs design can reduce their usage restrictions such as production costs and the time required for investigation of their activity and toxicity. In this study, two short peptides were designed based on direct and reverse mirror repeats of GLWQKI conserved sequence from Caerin 4 family that called dCar12 and rCar12. Also, Caerin 4.1 was synthesized without primary GLWQKI sequence and named Car . Following the synthesis of peptides, their antimicrobial properties, cytotoxicity, secondary structure, and mode of action were further evaluated. Results indicated that rCar12 had a good antibacterial activity (at an MIC of 3.9-62.5 µg/ml), while Car did not have any antimicrobial properties. Cytotoxicity of rCar12 at MICs range was <5%, which is much less than Caerin 4.1. In conclusion, rCar12 with reverse mirror repeat has different functional properties compared with dCar12. These results corroborate the fact that in two peptides with identical residues and length, the position and arrangement of amino acids are very important concerning peptide function. Moreover, GLWQKI sequence is highly crucial for the antimicrobial activity of Caerin 4 antimicrobial peptide family.
Caerin 4 是从蓝蛙（Litoria caerulea）中分离出的一类 AMPs。基于计算机的药物设计方法和机器学习算法用于 AMPs 设计可以降低其使用限制，例如生产成本以及对其活性和毒性进行研究所需的时间。在这项研究中，基于 Caerin 4 家族中 GLWQKI 保守序列的直接和反向镜像重复设计了两种短肽，分别称为 dCar12 和 rCar12。此外，还合成了没有主要 GLWQKI 序列的 Caerin 4.1，并将其命名为 Car。在合成肽后，进一步评估了它们的抗菌特性、细胞毒性、二级结构和作用模式。结果表明，rCar12 具有良好的抗菌活性（MIC 为 3.9-62.5μg/ml），而 Car 则没有任何抗菌特性。rCar12 在 MIC 范围内的细胞毒性<5%，远低于 Caerin 4.1。总之，与 dCar12 相比，具有反向镜像重复的 rCar12 具有不同的功能特性。这些结果证实了这样一个事实，即在具有相同残基和长度的两个肽中，氨基酸的位置和排列对于肽的功能非常重要。此外，GLWQKI 序列对于 Caerin 4 抗菌肽家族的抗菌活性至关重要。
