Three new antimicrobial peptides from the scorpion Pandinus imperator

Area of Science:

• Biochemistry
• Molecular Biology
• Pharmacology

Background:

• Scorpion venom is a rich source of bioactive peptides.
• Antimicrobial peptides (AMPs) are crucial in innate immunity.
• Antibiotic resistance necessitates the discovery of novel antimicrobial agents.

Purpose of the Study:

• To identify and characterize novel cysteine-free venom peptides from Pandinus imperator.
• To evaluate the antimicrobial and hemolytic activities of these novel peptides.
• To explore the potential of these peptides as therapeutic agents against antibiotic-resistant bacteria.

Main Methods:

• cDNA cloning strategy was employed to identify novel peptides.
• Peptide sequences were analyzed for structural features (α-helical, cationic, amphipathic).
• Antimicrobial assays were performed against Gram-positive, Gram-negative bacteria, and fungi.
• Toxicity was assessed via hemolytic activity assays against human red blood cells.

Main Results:

• Three novel cysteine-free peptides, Pantinin-1, Pantinin-2, and Pantinin-3, were identified.
• All three peptides demonstrated significant antimicrobial activity against Gram-positive bacteria and fungi.
• Pantinin-3 exhibited potent inhibition against vancomycin-resistant Enterococcus (VRE).
• Low hemolytic activity was observed for all three peptides against human red blood cells.

Conclusions:

• The identified Pantinin peptides are small, linear, cationic antimicrobial peptides.
• Pantinin-3 shows promise for developing new treatments against VRE infections.
• These findings provide insights into scorpion AMPs and offer templates for novel antimicrobial drug design targeting resistant pathogens.