Abstract:

In this paper, we compared the existing marine animal origin antibacterial peptides reported (Toxin except) with the holothurian proteome, combined with bioinformatics software to design, screen holothurian antibacterial peptides, and to investigate their physicochemical properties, antibacterial activity, mechanism, biocompatibility and cellular activity. It was found that through software simulation and antibacterial activity prediction, 7 holothurian bacteriostatic peptides (H1~H7) were finally screened and solid-phase synthesized. Among them, H4 (RVHRFLRR) could inhibit the growth of Staphylococcus aureus, Pseudomonas aeruginosa, Vibrio vulnificus through bacterial membrane potential depolarisation or membrane permeabilisation. At a lower concentration (31.25 µg·mL^-1), it reduced the total bacterial count of S. aureus to 84.93%±4.21%(p<0.01), P. aeruginosa to 95.92%±0.52%(p<0.01) and V. vulnificus to 77.14%±1.37%(p<0.01). It was also found that H4 was biocompatible and did not exhibit haemolytic or cytotoxic properties at < 1000 µg·mL^-1. In addition, H4 may interact with cell membrane receptors (EGFR, VEGFR2, FGFR1, etc.) to promote cell migration. H4 significantly promoted the migration of L929 cells at both 62.50 µg·mL^-1 and 250 µg·mL^-1 (p<0.05). The above experimental results indicate that holothurian antibacterial peptide H4 is biocompatible, has both antibacterial and pro-healing effects, and can be used as a potential functional active substance for the repair and regeneration of infected wounds.

Key words: Holothuroidea, antibacterial peptide, bioinformatics, cell migration