Wrighton N C, Balasubramanian P, Barbone F P, Kashyap A K, Farrell F X, Jolliffe L K, Barrett R W, Dower W J
Affymax Research Institute, Palo Alto, CA 94304, USA.
Nat Biotechnol. 1997 Nov;15(12):1261-5. doi: 10.1038/nbt1197-1261.
We have synthesized a chemically defined, dimeric form of an erythropoietin mimetic peptide (EMP) that displays 100-fold increased affinity for the erythropoietin receptor (EPOR) and correspondingly elevated potency in cell-based assays and in mice. The dimeric EMP1 was synthesized using a C-terminal lysine residue as a branch point. A beta-alanine residue was coupled to the main-chain (alpha) amino group of the lysine residue in order to provide a pseudosymmetrical scaffold where both the side-chain and main-chain were of approximately equal length. Using an orthogonal protection system, independently disulphide-cylized EMP1 moieties were synthesized upon this scaffold. The proposed mechanism of increased potency of the dimer over the parental compound EMP1 is consistent with the structure of a cocrystal of EMP1 and the extracellular domain of the EPOR in which a noncovalent peptide dimer is seen spanning the cleft between two molecules of the EPOR extracellular domain.
我们合成了一种化学结构明确的促红细胞生成素模拟肽（EMP）二聚体形式，其对促红细胞生成素受体（EPOR）的亲和力提高了100倍，在基于细胞的试验和小鼠实验中相应地增强了效力。二聚体EMP1是利用C末端赖氨酸残基作为分支点合成的。将一个β-丙氨酸残基连接到赖氨酸残基的主链（α）氨基上，以提供一个假对称支架，其中侧链和主链长度大致相等。使用正交保护系统，在此支架上合成了独立的二硫键环化的EMP1部分。所提出的二聚体相对于亲本化合物EMP1效力增强的机制与EMP1和EPOR细胞外结构域的共晶体结构一致，在该共晶体中可以看到一个非共价肽二聚体跨越EPOR细胞外结构域两个分子之间的裂隙。
