Cloning, Expression, and Purification of Antimicrobial Peptide LL-37 and Assessment of its Antimicrobial Effectiveness on Multiple-Drug-Resistant Acinetobacter Baumannii

Abstract

Background: Now a day, antibiotic resistance is a global problem. A way to solve this problem is production of alternative drugs. In this regard, today so many researches on antimicrobial peptides against pathogens are being done. LL-37 peptide is one of these peptides that is cationic and has antibacterial, antiviral, and anticancer activity. This project aimed to study the antimicrobial effectiveness of peptide LL-37 on multiple-drug-resistant (MDR) Acinetobacter baumannii. Methods: First, the LL-37 gene was linked to the pET-32a vector; then, recombinant DNA was transformed into the host bacteria and inducted to produce proteins. After the production and purification of recombinant proteins, to activate the protein, dialysis was performed in phosphate buffered saline (PBS). Then, the efficiency of peptide LL-37 on multiple-drug-resistant Acinetobacter baumannii was tested using common laboratory tests such as minimum inhibitory concentration (MIC). Findings: The minimum inhibitory concentration of LL-37 on Acinetobacter baumannii ATCC19606 was 1.5 µg/ml. In addition, the activity test showed that the recombinant proteins could inhibit the growth and decay the bacteria. Conclusion: The results of this study show that LL-37 protein, in comparison to other peptides and drugs in other studies, is more efficient and in low concentration can cause destruction of bacteria. This can herald a bright future for the treatment of infections caused by multiple-drug-resistant Acinetobacter baumannii.

Keywords

• LL-37 antibacterial peptide
• Antimicrobial drug resistance
• Acinetobacter baumannii