摘要
为解析不同类型氨基酸残基对天然胶原热稳定性的影响,以更贴近天然胶原序列中低亚氨基的异源三聚体abc为研究主体,设计不同的突变胶原序列,以圆二色谱法测定不同氨基酸对胶原热稳定性的影响,即倾向性。同时统计了天然胶原序列中各氨基酸的出现频率,并基于氨基酸倾向性计算预测了天然Ⅰ型胶原蛋白的局部热稳定性值。结果显示:X位的Ala、Leu和Glu、以及Y位的Gln、Thr、Ala和Arg既具有较高的倾向性,又具有较高的出现频率;天然Ⅰ型胶原蛋白序列可分为2种类型的区域:一种是可促进二级结构形成的高稳定性区域:另一种是对某些生命过程起到关键作用的低稳定性区域;同时具备高热稳定性和高出现频率的氨基酸,对天然胶原蛋白的稳定性起到关键作用。
In order to analyze the effect of different amino acid residues on the thermal stability of natural collagen.The heterotrimer abc,which better mimics the low-imino content of natural collagen,was used as the research host.Different mutant collagen sequences were designed,propensities of different amino acids were considered as their thermal stability measured with circular dichroism.At the same time,the frequency of amino acids in natural collagen sequence was calculated.Based on the propensities,local stability of typeⅠcollagen was predicted computationally.The results show that Ala,Leu and Glu at X-position and Gln,Thr,Ala and Arg at Y-position have both high propensities and high frequently occurring frequencies.The predicted local stability suggested that typeⅠcollagen may be divided into two types of regions.One type is high-stability regions for folding of the secondary structure and the other type is low-stability ones,which may play an important role in dynamics of biological processes.The study shows that amino acids with high thermal stability and high frequency play a key role in the stability of natural collagen.
作者
刘晗
郑虹宁
张瑞雪
许菲
LIU Han;ZHENG Hongning;ZHANG Ruixue;XU Fei(Ministry of Education Key Laboratory of Carbohydrate Chemistry and Biotechnology/School of Biotechnology,Jiangnan University,Wuxi 214122, China)
出处
《华中农业大学学报》
CAS
CSCD
北大核心
2020年第3期105-112,共8页
Journal of Huazhong Agricultural University
基金
国家自然科学基金项目(51603089,21603088)。
