Cytotoxic evaluation of natural and synthetic callipeltins: a revision of cytotoxicity of callipeltin B

The cytotoxic evaluation of natural and synthetic callipeltins is described. Cyclic depsipeptide callipeltin B and linear peptides callipeltins E and M synthesized by us showed no cytotoxic activity. In contrast, natural callipeltin B purified from <i>Callipelta</i> sp. showed CC₅₀ = 130 μM against Hela cells. We found that purified callipeltin B included the contamination of callipeltins C and H at a ratio of approximately 15%. These results suggested that the cytotoxicity of natural callipeltin B was derived from callipeltins C and H.

本研究报道了天然与合成型卡皮肽（callipeltins）的细胞毒性评价工作。本课题组合成的环状缩酚肽类卡皮肽B（callipeltin B）与线型肽类卡皮肽E、M均未表现出细胞毒性活性。与之相反，从卡皮塔海绵属（Callipelta sp.）中纯化得到的天然卡皮肽B，对海拉（HeLa）细胞的半数细胞毒性浓度（CC₅₀）为130 μM。我们发现，该纯化产物中以约15%的比例混杂有卡皮肽C与H。上述结果表明，天然卡皮肽B所表现出的细胞毒性，实际来源于混杂的卡皮肽C与H。