摘要
以牛乳铁蛋白肽片段LFcinB18-28为母肽,在保留其高电荷、强疏水性的基础上,依据对称结构设计理念,引入精氨酸和色氨酸替换,设计出新型抗菌肽KWRRWQWRRWK-NH2(KW-WK)。采用圆二色谱法、微量稀释法、噻唑蓝法等方法分析KW-WK的二级结构、抑菌活性、溶血活性、细胞毒性及稳定性。结果表明,KW-WK肽在模拟水环境中呈无规卷曲状,在模拟细胞膜环境中,则呈α-螺旋结构;KW-WK肽的抑菌性强,最小抑菌浓度为4～128μmol/L;溶血率低,当肽浓度为256μmol/L时,其溶血率小于5%;细胞毒性小;治疗指数为9.14,细胞选择性高;热稳定性好,100℃处理1 h后仍保持较强的抑菌活性,酶稳定性较LFcinB18-28母肽有极大的提高。因此,新型抗菌肽KW-WK在食品、医药和畜牧等领域都显示出巨大的应用潜力。
This study designed a new anti-microbial peptide KWRRWQWRRWK-NH2 （KW-WK） with the fragment of bovine lactoferricin LFcinB18-28 as parent peptide. Apart from retaining the high charge and strong hydrophobicity of the parent peptide, arginine （R） and tryptophan （W） replacement was introduced to design this anti-microbial peptide based on the concept of symmetrical structure. The secondary structure, antibacterial activity, hemolysis activity, cell toxicity and stability of KW-WK were determined by circular dichroism spectroscopy, broth microdilution and 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl-2H-tetrazolium bromide （MTT） method. The results showed that KW-WK existed in a random coil structure in aqueous solution. However, it was α-helical in the simulated environment of cell membrane. The minimal inhibitory concentration （MIC） of KW-WK ranged from 4 to 128 μmol/L, suggesting that its bacteriostatic activity was strong. The hemolysis rate was less than 5% when the concentration of KW-WK was 256 μmol/L. This result showed that its hemolysis activity was low. The therapeutic index of KW-WK was 9.14, and its cytotoxicity was relatively low. Thus, its cell selectivity was relatively high. In addition, after heat treatment 100 ℃ for 1 h, KW-WK still possessed rather high antibacterial activity. The enzymatic stability of KW-WK was greatly improved as compared to LFcinB18-28. Therefore, the new anti-microbial peptide KW-WK has shown a great application potential in the fields of food, medicine, livestock etc.
作者
王海梅
李盈盈
侯俊财
姜成刚
李东飞
卢佳音
赵悦含
逄诗玥
WANG Haimei;LI Yingying;HOU Juncai;JIANG Chenggang;LI Dongfei;LU Jiayin;ZHAO Yuehan;PANG Shiyue(College of Food Science,Northeast Agricultural University,Harbin 150030,China;Harbin Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Harbin 150001,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2018年第20期57-62,共6页
Food Science
基金
"十三五"国家重点研发计划重点专项(2016YFD0400605)
关键词
KW-WK肽
抑菌活性
溶血活性
细胞毒性
稳定性
KW-WK peptide
antibacterial activity
hemolytic activity
cytotoxicity
stability
