Carbonell X, Villaverde A
Institut de Biologia Fonamental, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Biochem Biophys Res Commun. 1998 Mar 17;244(2):428-33. doi: 10.1006/bbrc.1998.8285.
The tailspike protein (TSP) of bacteriophage P22 is a homotrimeric multifunctional protein responsible for recognition and hydrolysis of Salmonella typhimurium host receptors. Once properly folded, TSP shows an unusual stability to temperature and detergent denaturation, prompting the analysis of TSP as a framework for the positioning of heterologous protein segments. We have explored the flexibility of inner sites and both amino and carboxy termini to accommodate foreign peptides for phage display. In the examined inner sites, TSP is extremely sensitive to minor sequence modifications, the folding intermediates being rapidly degraded. However, both the amino and carboxy termini are tolerant to peptide fusions, rendering stable and functional chimeric proteins. Surprisingly, the amino terminus, which connects the tail to the neck structure, can accept large peptide fusions, and the foreign amino acid stretches are solvent-exposed and highly antigenic on assembled, infectious virus particles.
噬菌体P22的尾刺蛋白（TSP）是一种同源三聚体多功能蛋白，负责识别和水解鼠伤寒沙门氏菌宿主受体。一旦正确折叠，TSP对温度和去污剂变性表现出异常的稳定性，促使人们将TSP作为定位异源蛋白片段的框架进行分析。我们已经探索了内部位点以及氨基和羧基末端的灵活性，以容纳用于噬菌体展示的外源肽。在所研究的内部位点中，TSP对微小的序列修饰极其敏感，折叠中间体迅速降解。然而，氨基和羧基末端都能耐受肽融合，产生稳定且有功能的嵌合蛋白。令人惊讶的是，连接尾部和颈部结构的氨基末端可以接受大的肽融合，并且在组装好的感染性病毒颗粒上，外源氨基酸片段暴露于溶剂中且具有高度抗原性。
