Antimicrobial peptide ctriporin

Antibiotic-resistant microbes, such as methicillin-resistant Staphylococcus aureus, seriously threaten human health. The outbreak of "superbugs" in recent years emphasizes once again the need for the development of new antimicrobial agents or resources. Antimicrobial peptides have an evident bactericidal effect against multidrug-resistant pathogens. In the present study, a new antimicrobial peptide, ctriporin, was cloned and characterized from the venom of the scorpion Chaerilus tricostatus, an animal which has not yet been explored for toxic peptide resources. The MICs of ctriporin against Staphylococcus aureus, Bacillus thuringiensis, Bacillus subtilis, Micrococcus luteus, and Candida albicans are 5 to 20 μg/ml. Meanwhile, it MIC against clinical antibiotic-resistant bacterial strains is 10 μg/ml. Furthermore, the potential for ctriporin to be used as a topical antibiotic for treating staphylococcal skin infections was investigated. External use of the peptide ctriporin dramatically decreased the bacterial counts and cured skin infections in mice. In addition, ctriporin demonstrates antimicrobial efficacy via the bactericidal mechanism of rapid cell lysis. Together, these results suggest the potential of developing ctriporin as a new topical antibiotic.

Background: Scorpion venom is the most expensive and deadly venom with exciting medical prospects and having a potential as a source of drug candidates. A number of scorpion venom peptides have shown promising site specificity and are involved in the regulation of biological mechanisms. Due to the structural and functional specificity, the scorpion peptides are widely used for the development of specific drugs especially for the cardiovascular and other immune diseases. In this review, we summarize scorpion venom's biological activities such as antimicrobial, antiviral, anti-cancerous and in immune diseases. Evolutionary perspective of peptides derived from different scorpion venoms are also described in this review. The most significant venom peptides are; Ctriporin, Chlorotoxins (cltx), Neopladine I and II, Meucin 24, Meucin 25 and Hp 1090. The most recognized scorpion species with pharmaceutical activities are; Pandinus imperator, Chaerilustricostatus, Buthus martensii, Mesobuthus eupeus, Leiurus quinnquestriatus, Tityus discrepans and Heterometrus bengalensis. Conclusion: The role of peptides in cardiovascular events and in treating osteoporosis signifies their importance. The role of peptides against pathogens, skin infections, pain-relieving effects, anti-malarial and anti-viral effects are discussed in detail. We further, summarized the classification of scorpion peptides among different toxins, their evolutionary process and the pattern of scorpion venom resource analysis.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is becoming a troublesome issue worldwide, and anti-CRAB drug research and development is urgently needed. To identify new anti-CRAB drug leads, we investigated seven scorpion venom-derived α-helical peptides that differ in their sequence composition and length. Three peptides, Hp1404, ctriporin and Im5, showed antimicrobial activities against Acinetobacter baumannii. Further antimicrobial assays revealed that Hp1404 exhibited the best cell selectivity with high anti-CRAB and low hemolytic activities. Fluorescence assays demonstrated that Hp1404 can induce dose-dependent disruptions of the bacterial cell membrane, implying a membrane-lytic mode of action. Taken together, our work sheds light on the potential of the scorpion venom-derived peptide Hp1404 for the development of novel antimicrobial agents against CRAB infections.