Current Protein & Peptide ScienceCurrent Protein & Peptide ScienceCurrent Protein & Peptide Science1389-20371875-5550Bentham Science64543710.2174/0113892037291252240528110516Life SciencesResearch ArticleEvaluation of Novel HLM Peptide Activity and Toxicity against Planktonic and Biofilm Bacteria: Comparison to Standard AntibioticsMasadehMajedinfo@benthamscience.netAlshogranHaneeninfo@benthamscience.netAlsaggarMohammadinfo@benthamscience.netSabiSalsabeelinfo@benthamscience.netAl MomanyEnaaminfo@benthamscience.netMasadehMajdinfo@benthamscience.netAlrabadiNasrinfo@benthamscience.netAlzoubiKareminfo@benthamscience.netDepartment of Pharmaceutical Technology, Faculty of Pharmacy, Jordan University of Science and TechnologyDepartment of Biology, Faculty of Science, The Hashemite UniversityDepartment of Clinical Pharmacy and Pharmacy Practice, Faculty of Pharmaceutical Sciences, The Hashemite UniversityDiscipline of Clinical Pharmacy, School of Pharmaceutical Sciences, University Sains MalaysiaDepartment of Pharmacology, Faculty of Medicine, Jordan University of Science and TechnologyDepartment of Pharmacy Practice and Pharmacotherapeutics, University of Sharjah01102024251082684311012025Copyright ©; 2024, Bentham Science Publishers2024Bentham Science Publishershttps://journals.eco-vector.com/1389-2037/article/view/645437

Background:Antibiotic resistance is one of the main concerns of public health, and the whole world is trying to overcome such a challenge by finding novel therapeutic modalities and approaches. This study has applied the sequence hybridization approach to the original sequence of two cathelicidin natural parent peptides (BMAP-28 and LL-37) to design a novel HLM peptide with broad antimicrobial activity.

Methods:The physicochemical characteristics of the newly designed peptide were determined. As well, the new peptide’s antimicrobial activity (Minimum Inhibitory Concentration (MIC), Minimum Bacterial Eradication Concentration (MBEC), and antibiofilm activity) was tested on two control (Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922) and two resistant (Methicillin-resistant Staphylococcus aureus (MRSA) ATCC BAA41, New Delhi metallo-beta- lactamase-1 Escherichia coli ATCC BAA-2452) bacterial strains. Furthermore, synergistic studies have been applied to HLM-hybridized peptides with five conventional antibiotics by checkerboard assays. Also, the toxicity of HLM-hybridized peptide was studied on Vero cell lines to obtain the IC50 value. Besides the percentage of hemolysis action, the peptide was tested in freshly heparinized blood.

Results:The MIC values for the HLM peptide were obtained as 20, 10, 20, and 20 µM, respectively. Also, the results showed no hemolysis action, with low to slightly moderate toxicity action against mammalian cells, with an IC50 value of 10.06. The Biomatik corporate labs, where HLM was manufactured, determined the stability results of the product by Mass Spectrophotometry (MS) and High-performance Liquid Chromatography (HPLC) methods. The HLM-hybridized peptide exhibited a range of synergistic to additive antimicrobial activities upon combination with five commercially available different antibiotics. It has demonstrated the biofilm-killing effects in the same concentration required to eradicate the control strains.

Conclusion:The results indicated that HLM-hybridized peptide displayed a broad-spectrum activity toward different bacterial strains in planktonic and biofilm forms. It showed synergistic or additive antimicrobial activity upon combining with commercially available different antibiotics.

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