Abstract

Scorpion venom is a mixture of bioactive peptides, among which neurotoxins and antimicrobial peptides serve especially vital functions. Scorpion venom peptides in Buthidae species have been well described, but toxic peptides from non-Buthidae species have been under-investigated. Here, an antimicrobial peptide gene, Ctri9594, was cloned and functionally identified from the venom of the scorpion Chaerilus tricostatus. The precursor nucleotide sequence of Ctri9594 is 199 nt in length, including a 43 nt 5′ UTR, 115 nt 3′ UTR and 210 nt ORF. The ORF encodes 69 amino acid residues, containing a 21 aa signal peptide, 14 aa mature peptide, 3 aa C-terminal posttranslational processing signal and 31 aa propeptide. Multiple sequence alignment and evolutionary analyses show that Ctri9594 is an antimicrobial peptide in scorpion venom. The mature peptide of Ctri9594 was chemically synthesized with a purity greater than 95% and a molecular mass of 1484.4 Da. Minimum inhibitory concentrations (MICs) indicate that the synthesized mature peptide of Ctri9594 has inhibitory activity against Gram-positive bacteria (Bacillus thuringensis, Bacillus subtilis, Staphylococcus aureus and Micrococcus luteus) but not Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) or a fungus (Candida albicans). The antimicrobial mechanism of Ctri9594 is inferred to be related to its amphiphilic α-helix structure.

Highlights

  • The venom produced by scorpions to kill prey and defend against natural enemies is rich in bioactive components

  • These antimicrobial peptides are composed of 75–78 amino acid residues, with an N-terminal region similar to cecropins, with an amphiphilic α-helix structure and a C-terminal region containing a CSαβ motif

  • Long non-disulfide antimicrobial peptides are the second class and mainly include parabutoporin, pandinin-1, opistoporins and hadurin [7]. These antimicrobial peptides are composed of 41-44 amino acid residues, and their precursors include signal peptides, mature peptides and C-terminal propeptides

Read more

Summary

Introduction

The venom produced by scorpions to kill prey and defend against natural enemies is rich in bioactive components. This type of peptide has only been found in non-Buthidae scorpion species These antimicrobial peptides are composed of 75–78 amino acid residues, with an N-terminal region similar to cecropins, with an amphiphilic α-helix structure and a C-terminal region containing a CSαβ motif. Long non-disulfide antimicrobial peptides are the second class and mainly include parabutoporin, pandinin-1, opistoporins and hadurin [7] These antimicrobial peptides are composed of 41-44 amino acid residues, and their precursors include signal peptides, mature peptides and C-terminal propeptides. Short non-disulfide antimicrobial peptides are the third group, including BmKn2 and IsCT, among others [8,9] These members generally consist of 13-24 amino acid residues. Their precursor organization and structure (signal peptide, mature peptide and C-terminal propeptide) are the same as those of the second class of AMPs

Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call