摘要目的 观察体外无细胞核糖体表达系统筛选得到的、能与细菌膜结合的多肽的体外抑菌活性变化,初步评价该筛选系统的可行性.方法 采用核糖体展示系统和细胞膜模型筛选可结合于细胞膜的多肽,对筛选的多肽进行结构预测分析.选择形成α-螺旋结构可能性大、溶解性尚可的多肽(C13)进行合成.利用改良的微量肉汤稀释法测定C13和硫酸庆大霉素对G+(金黄色葡萄球菌)和G-(大肠杆菌、伤寒杆菌)细菌的抗菌活性--最小抑菌浓度(MIC)和最小杀菌浓度(MBC).结果 C13对试验细菌的MIC均为400 mg/L,但在现有浓度范围对试验菌的MBC则未测得.结论 体外无细胞核糖体表达系统筛选的抗菌肽C13具有一定的抑菌活性,表明利用人工膜模型和核糖体表达进行抗菌肽筛选的方法是可行的,但有效抗菌肽的筛选需进一步的抑菌试验证实.

abstractsObjective To investigate the activity of the peptids that were screened by cell-free ribosome display system and combined with bacterial membrane against bacterium in vitro, and to evaluate the screening system feasibility. Methods The peptid (C13) was synthesized based on the protein structure prediction results that showed C13 with a alpha-helix and good dissolution. In vitro, susceptibilities of C13 and gentamicin sulphate were evaluated against several Gram-positive (Staphylococcus aureus) and Gram-negative bacterium (Escherichia coli, Bacillus typhi), using modified broth microdilution method. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were measured. Results The MIC of C13 against all test bacterium was 400 mg/L. The MBC of C13 against the test bacterium was not detected within the concentration range. Conclusions The peptids C13 screened by cell-free ribosome display system have aitimicrobial activity in some content. However it is necessary for discovering the effective antibacterial peptides to validate by against bacterium experiments. This method of peptids screening by artificial membrane and ribosome display is successful.