Gebhardt K, Lauvrak V, Babaie E, Eijsink V, Lindqvist B H
Biotechnology Centre of Oslo, University of Oslo, Norway.
Pept Res. 1996 Nov-Dec;9(6):269-78.
Phase clones with affinity for polystyrene/polyurethane magnetic particles were isolated from a 10-men peptide display library. Sequence analysis revealed that 40 out of 80 clones contained the consensus WXXWXXXW. Some of the selected phages showed high surface activity and adsorbed to plastic surfaces even in the presence of blocking agents or surfactants. Covalent attachment of a synthetic peptide (KG), carrying one of the selected sequences to alkaline phosphatase (AP) or bovine serum albumin (BSA) enhanced binding of AP to a wide range of materials and improved the ability of BSA to prevent binding of antibodies and phages to polystyrene. Interestingly, the WXXW/XXXW motif occurs in the beta- and gamma-chains of the natural "adhesive" protein fibrinogen, and a synthetic peptide carrying the gamma-chain 369-376 sequence turned out to have essentially the same binding properties as the KG peptide. Furthermore, adsorption in different types of polystyrene was similar for AP carrying either the KG or gamma-chain peptide intact fibrinogen and plasmin-generated fragment D1. The latter fragment contains two copies of the WXXWXXXW motif but lacks the alpha-chain: protuberances previously implicated in fibrinogen adsorption. Thus, our study may have revealed a hitherto unknown structural determinant for fibrinogen's adsorptivity, located in the 13-kDa C terminal region of the gamma-chain.
从一个包含10种肽的展示文库中分离出了对聚苯乙烯/聚氨酯磁性颗粒具有亲和力的噬菌体克隆。序列分析表明，80个克隆中有40个包含一致序列WXXWXXXW。一些筛选出的噬菌体表现出高表面活性，即使在存在封闭剂或表面活性剂的情况下也能吸附到塑料表面。将携带所选序列之一的合成肽（KG）共价连接到碱性磷酸酶（AP）或牛血清白蛋白（BSA）上，增强了AP与多种材料的结合，并提高了BSA防止抗体和噬菌体与聚苯乙烯结合的能力。有趣的是，WXXW/XXXW基序出现在天然“粘附”蛋白纤维蛋白原的β链和γ链中，并且携带γ链369 - 376序列的合成肽与KG肽具有基本相同的结合特性。此外，携带KG或γ链肽的完整纤维蛋白原和纤溶酶生成的片段D1的AP在不同类型聚苯乙烯上的吸附情况相似。后一个片段包含两个WXXWXXXW基序拷贝，但缺少α链：先前认为与纤维蛋白原吸附有关的突出部分。因此，我们的研究可能揭示了纤维蛋白原吸附性的一个迄今未知的结构决定因素，位于γ链的13 kDa C末端区域。
