Structure-activity relationships of the intramolecular disulfide bonds in coprisin, a defensin from the dung beetle

BMB Reports

Hyemin Choi^2¹  Ho Kim^4²  Ha Hyung Kim^3³  Jaeho Lee^1⁴  Daeun Lee^1⁵ 

[1] College of Pharmacy, Chung-Ang University, Seoul 156-756^3;Department of Agricultural Biology, Natural Academy of Agricultural Science, RDA, Suwon 441-707, Korea^5;School of Life Sciences and Biotechnology, College of Natural Science, Daejin University, Pocheon 487-711^4;School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712^1;School of Life Sciences, KNU Creative BioResearch Group (BK21 plus program), College of Natural Sciences, Kyungpook National University, Daegu 702-701^2

关键词: Antimicrobial peptide;   

DOI  :  

学科分类：生物化学/生物物理

来源: Korean Society for Biochemistry and Molecular Biology

【 摘 要 】

Defensins, which are small cationic molecules produced by organisms as part of their innate immune response, share a common structural scaffold that is stabilized by three disulfide bridges. Coprisin is a 43-amino acid defensin-like peptide from Copris tripartitus. Here, we report the intramolecular disulfide connectivity of cysteine-rich coprisin, and show that it is the same as in other insect defensins. The disulfide bond pairings of coprisin were determined by combining the enzymatic cleavage and mass analysis. We found that the loss of any single disulfide bond in coprisin eliminated all antibacterial, but not antifungal, activity. Circular dichroism (CD) analysis showed that two disulfide bonds, Cys20-Cys39 and Cys24- Cys41, stabilize coprisin’s α-helical region. Moreover, a BLAST search against UniProtKB database revealed that coprisin’s α-helical region is highly homologous to those of other insect defensins.

【 授权许可】

Unknown