中文摘要：

粘细菌作为第三大类次级代谢产物产生菌,是挖掘抗肿瘤新药物的重要资源。将本实验室保藏的粘细菌菌株Myxococcus macrosporus STXZ54进行发酵培养后,通过对发酵液进行硫酸铵沉淀、丙酮沉淀等,分析了该菌株发酵液中抗肿瘤活性物质的性质,采用高效液相色谱技术对发酵液中的抗肿瘤活性物质进行了分离,并对该物质进行了肿瘤细胞毒性的测定,利用激光共聚焦显微镜观察该物质作用B16后的亚细胞结构变化。实验结果表明该物质可能为常温下性质较稳定的蛋白质类化合物,纯化到的单一组分WGF5对B16,Hela,MCF-7,Hep-3B肿瘤细胞均具有较强的抑制作用,其作用48 h的IC_（50）（最低半抑制浓度）分别为2.767μg/ml、2.204μg/ml、3.758μg/ml、3.073μg/ml。MTT实验以及激光共聚焦显微镜下观察分析发现,蛋白WGF5能够明显改变细胞形态并最终导致肿瘤细胞死亡。从粘细菌Myxococcus macrosporus STXZ54分离到的活性物质具有广谱高效的抗肿瘤效果,有开发成抗肿瘤新药物的潜在价值。

英文摘要：

Myxobacteria are known to be the third category of bacteria, which produce metabolites of potential anticancer effects. Here the lab-stored Myxococcus macrosporus STXZ54 was cultured, and components of its supematants were attained by ammonium sulfate or acetone precipitation. Cytotoxic effects of the sediments were evaluated through an in vitro method. Further, the unique protein, WGF5, was successfully separated by high performance liquid chromatography from the myxobacteria. Its inhibitory effects on cancer cells were also analyzed by MTT assay. Simultaneously, confocal microscopy was employed to observe the alterations of B16 subcellular structure after treatment by WGFS. The results demonstrated that WGF5 was a very stable protein under room temperature and could efficiently inhibit the growth of B16, Hela, MCF-7 and Hep-3B cancer cells. The ICs0 of WGF5 after 48 h incubation with the cancer cells was 2. 767 μg/ml, 2. 204 μg/ml, 3. 758 μg/ml and 3. 073 μg/ml, respectively. Moreover, MTT assay and confocal microscopy observation found that WGF5 probably restrains the proliferation of the cancer cells through changing the cell morphology. Briefly, this study indicates that the WGF5 of Myxococcus macrosporus STXZ54 has an broad-spectrum anticancer effects and could be used for cancer therapy in the near future.