从组合化学肽库中筛选亲和配基

在亲和色谱研究中 ,建立适合于某种分离对象的亲和色谱体系的关键是寻找适合的亲和配基 .小肽亲和配基具有性质稳定、合成简单、价格低及生物相容性好等特点1] ,但这类配基也存在着亲和力弱或选择性低的缺点 .因此 ,如何寻找小肽配基以及如何提高小肽配基的亲和力和选择性的问题引起了人们的关注与重视 1～ 3 ] .组合化学法是一种快速制备大量相关或同类化合物的革新性的方法 4 ] ,组合肽库包括噬菌体展示肽库和合成肽库 ,这两类肽库均可用于小肽配基的筛选与优化 1,5] .组合化学法尽管有效 ,但以小肽为目的物进行筛选时 ,往往因肽 -肽…

Screening of Affinity Peptide Ligands from Combinatorial Peptide Libraries

A new method for the rapid and efficient screening of affinity ligands to biological targets is reported. The fusion peptide of influenza virus A was used as the model target and immobilized on the PGMA beads. Antisense peptide YRSKQA of fusion peptide was chosen as the lead compound. The special positional scanning peptide libraries were designed based on YRSKQA and synthesized by utilizing solid phase peptide synthesis manually. The libraries were YRSKQX, YRSKXA, YRSXQA, YRXKQA, YXSKQA and XRSKQA, where X represented 18 L-amino acids(except for Cys and Trp). Each library was screened by affinity chromatography. The eluates from the fusion peptide affinity column were collected and analyzed by RP-HPLC and MS, respectively, in order to determine the kind of X at each position. After the preferred residues of six positions were decided, the two preferred peptide sequences, GRGKHK and TRGKHK, were obtained. The dissociation constants of GRGKHK, TRGKHK and YRSKQA, were 3.35×10-6, 5.24×10-6and 1.15×10-5 mol·L-1, respectively. The preferred peptides showed the higher affinity binding to immobilized fusion peptide than the lead peptide.