【摘要】 为设计研发新型天蚕素类抗菌肽(Cecropin-like antibacterial peptide,CLP),本研究参照抗菌肽Cecropin P1的作用机理和氨基酸组成,通过人工方法设计合成CLP,并分别测定其体外和体内抗菌活性。体外抑菌试验结果显示,新型CLP对金黄色葡萄球菌(ATCC29213)、禽多杀性巴氏杆菌(CVCC474)、鸡白痢沙门氏菌(ATCC10398)、鸡致病性大肠杆菌O1均具有良好的抑菌活性,对这4种细菌的最小抑菌浓度(MIC)分别为6.25μg/mL、1.56μg/mL、3.12μg/mL和6.25μg/mL。酸稳定性试验显示,新型CLP在pH值为6~8时活性最高,热稳定性试验显示新型CLP于100℃加热2 h后仍具有抑菌活性。在对鸡白痢沙门氏菌感染雏鸡的体内疗效试验中,新型CLP显示了良好的治疗效果。本研究为临床上设计有效的天蚕素类抗菌肽提供了参考数据。更多还原

【Abstract】 The purpose of this study is to design and evaluate the antibacterial activity of a novel Cecropin-like antibacterial peptide(CLP). In this study, based on antibacterial mechanism and amino acid composition of antibacterial peptide Cecropin P1,we describe the design and synthesis of the CLP, and report its biological characteristic. Antibacterial activity assay in vitro showed that the CLP had higher antibacterial activity against Staphylococcus aureus(ATCC29213), Pasteurella multocida(CVCC474),Salmonella pullorum(ATCC10398) and enteropathogenic Escherichia coli O1. The minimal inhibitory concentrations(MICs) of the CLP against the four bacterial strains were 6.25 μg/mL, 1.56 μg/mL, 3.12 μg/mL and 6.25 μg /mL, respectively. Moreover,the CLP was able to keep antibacterial activity after being boiled at least 120 minutes and had higher stability in pH6 to 8. The results of therapeutic tests showed that the survival rate was significant higher(p<0.05) in chicks of the CLP treated group compared to the chicks in S.pullorum infection control group, which displayed the CLP had preferable curative effect for treatment against S.pullorum infection in vivo. These data indicate that the CLP is a potential new type of antibacterial biological agent. This study provides valuable support for further development of antibacterial peptides.更多还原