多肽dhvar4的抗细菌活性和细胞毒性研究

Antibacterial Activity and Cytotoxicity of Polypeptide dhvar4

目的 研究多肽dhvar4的抗细菌活性及其细胞毒性。方法 人工合成多肽dhvar4 ,测定不同质量浓度dhvar4作用后的细菌生长曲线,检测dhvar4抗细菌活性;用MTT法检测不同质量浓度dhvar4对L- 0 2、ECV- 30 4、2 93和3T3细胞的细胞毒性;用溶血性实验检测不同质量浓度dhvar4对血红细胞的溶血性。结果 dhvar4在4μg/m l质量浓度以上对金黄色葡萄球菌BAA4 2和肠球菌EF36 4 18的生长有明显的抑制作用。在15 0 μg/m l高质量浓度条件下,哺乳动物正常细胞存活率为6 8%～92 % ,其L D50 大于15 0 μg/m l。最大检测质量浓度(180 μg/ml)下,dhvar4对血红细胞几乎没有溶血作用。结论 dhvar4具有抗细菌作用,无明显细胞毒性和溶血性,具有开发成为安全高效抗细菌药物的潜在价值。

Objective To investigate the antibacterial activity and the cytotoxicity of polypeptide dhvar4. Methods Solid-phase synthesized dhvar4 was manufactured by MeiLian Biotech Co.Ltd.; we evaluated its antibacterial effect, using the growth curve of bacteria after the bacteria being treated with different concentration of dhvar4. The cytotoxicity of dhvar4 on L-02, ECV-304, 293, 3T3 cells was investigated by MTT assay, and human erythrocytes were subimitted to hemolytic assay. Results dhvar4 inhibited the growth of Enterococcus faecium 36418 and Staphylococcus aureus BAA42 only at the concentration of 4 μg/ml. The viability of mammalian cells remained 68%-92% even when the concentration of dhvar4 reached 150 μg/ml. The LD_ 50 (median lethal dose) was determined to be higher than 150 μg/ml. And very low hemolytic activity of dhvar4 was detected even at the highest protein concentration tested (180 μg/ml). Conclusion dhvar4 possesses antibacterial activity and has little cytotoxicity to mammalian cells. These results suggest that dhvar4 has great potential in the development of effective and safe antimicrobial agent.