The emergence of antibiotic resistance makes the development of a new generation of powerful antimicrobials able to kill super bugs more essential than ever. Linear scorpion venom peptides are a small group of venom peptides that display antimicrobial, anticancer, and anti-inflammatory activities, although, in many cases, they exhibit strong hemolytic activity hindering their further development. Here, we present an improved synthesis of Mucroporin, a linear scorpion peptide of 17 amino acids, isolated from the Chinese Scorpion Lychas Mucronatus. The synthesis was conducted on a Microwave Peptide Synthesizer (Biotage Initiator+) by using an ultra-fast method at elevated temperature, 90 °C, avoiding some common steps in the conventional methods and reducing the total synthesis time by 40% and the total waste by 50% without affecting the purity of the crude peptide, which was calculated to 90%, making the final purification easier than ever. The synthesis was performed by using N-butyl-2-pyrrolidone (NBP), a green alternative to DMF solvent, which is under restriction for use in therapeutic peptides as of December 2023 in EU. Mucroporin was tested for its antimicrobial activity against gram-positive and gram-negative bacterial strains (Escherichia coli, Staphylococcus epidermidis, Neisseria subflava and Streptococcus pneumoniae Strain) by the serial dilution method in liquid cultures of bacteria with a cell density of ~2 × 105 CFU/mL in different concentrations and incubated for 24 h, and then the optical density was measured at 600 nm. Ampicillin was used as a positive control at a concentration of 100 μg/mL. The peptide completely inhibited the growth of Staphylococcus epidermidis and Streptococcus pneumoniae, as expected from earlier studies. Of particular interest is the inhibitory activity of Neisseria subflava at a final concentration of 120 μg/mL. This is the first time that mucroporin has ever been reported to be effective against gram-negative strains; therefore, its activity against Neisseria subflava is of particular interest.
Author Contributions
Conceptualization, Y.S. and C.P.; methodology, Y.S. and T.P.; investigation, A.M. and T.P.; resources, Y.S. and C.P.; data curation, Y.S. and C.P.; writing—original draft preparation, A.M. and T.P.; writing—review and editing, Y.S. and T.P.; supervision, Y.S.; project administration, Y.S.; funding acquisition, Y.S. and C.P. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Not applicable.
Conflicts of Interest
The authors declare no conflict of interest.
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