Hamadan University of Medical Sciences Avicenna Journal of Clinical Microbiology and Infection 2383-0298 6 1 2019 02 01 The New Insight for Novel Antimicrobial Peptides Designing by Computational Design and Improvement of an Antimicrobial Peptide Derivate of LL-37 15 20 10.34172/ajcmi.2019.04 EN Masoud Keikha https://orcid.org/0000-0003-1583-9936 Hossein-Ali Rahdar Morteza Karami-Zarandi Davood Azadi kiarash Ghazvini https://orcid.org/0000-0002-8538-1425 Journal Article 10.34172/ajcmi.2019.04 2018 12 08 2019 02 19 Background: LL-37 is one of the well-known antimicrobial peptides which is effective on the extended expecetrome of microbial pathogens. The aim of this study was to design a modified digital analog of LL-37 with enhanced antimicrobial activity and restricted toxicity of the host cell. Methods: Online databases and software were used for determining LL-37 characteristics such as hydrophobicity, Booman index, and hemolysis probability. Variant structures based on the replacement of leucine and lysine with tryptophan and arginine were calculated as well. Finally, the best sequence was selected and analyzed for approving as an antimicrobial peptide. Results: The antibacterial characteristics of LL-37 were improved by replacing the arginine and tryptophan and according to systemic calculations, it was defined that this peptide is an antimicrobial peptide by 97% confidential. Conclusions: In general, bioinformatics tools are considered as one of the most available and efficient tools for antimicrobial peptide designing. Therefore, future studies could use kLL-39 as an antimicrobial peptide and investigate its antimicrobial effects in vitro.