Isolation and Characterization of Antimicrobial Peptides with Unusual Disulfide Connectivity from the Colonial Ascidian Synoicum turgens

Marine Drugs

Johan Isaksson¹  DavidJ. Craik²  AaronG. Poth²  KineØ. Hansen³  CélineS. M. Richard⁴  Klara Stensvåg⁴  IdaK. Ø. Hansen⁴  Tor Haug⁴  AaronJ. C. Andersen⁴  Hans-Matti Blencke⁴ 

[1] Department of Chemistry, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway;Institute for Molecular Bioscience, The University of Queensland, Brisbane 4072, Queensland, Australia;Marbio, UiT The Arctic University of Norway, Breivika, N-9037, Tromsø, Norway;Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway;

关键词: marine;    ascidian;    peptide;    antimicrobial;    methionine oxidation;   

DOI  :  10.3390/md18010051

来源: DOAJ

【 摘 要 】

This study reports the isolation of two novel cysteine-rich antibacterial peptides, turgencin A and turgencin B, along with their oxidized derivatives, from the Arctic marine colonial ascidian Synoicum turgens. The peptides are post-translationally modified, containing six cysteines with an unusual disulfide connectivity of Cys¹-Cys⁶, Cys²-Cys⁵, and Cys³-Cys⁴ and an amidated C-terminus. Furthermore, the peptides contain methionine residues resulting in the isolation of peptides with different degrees of oxidation. The most potent peptide, turgencin A_Mox1 with one oxidized methionine, displayed antimicrobial activity against both Gram-negative and Gram-positive bacteria with a minimum inhibitory concentration (MIC) as low as 0.4 µM against selected bacterial strains. In addition, the peptide inhibited the growth of the melanoma cancer cell line A2058 (IC₅₀ = 1.4 µM) and the human fibroblast cell line MRC-5 (IC₅₀ = 4.8 µM). The results from this study show that natural peptides isolated from marine tunicates have the potential to be promising drug leads.

【 授权许可】

Unknown