Septide 多肽

Pyr-FFPLM-NH2

Pyr-Phe-Phe-Pro-Leu-Met-NH2

5

95.82

C₃₉H₅₃N₇O₇S

763.94

79775-19-2

119137

固相合成

Septide is a synthetic peptide with the amino acid sequence [pGlu⁶, Pro⁹]Substance P^9-11. It is known to have tachykinin-like actions despite its apparent lack of binding to any known tachykinin receptor initially. However, later studies have shown that Septide binds to the NK-1 receptor with high affinity.
Binding Affinity to NK-1 Receptor: In homologous binding assays, Septide has a Kd value of 0.55 ± 0.03 nM, indicating high-affinity binding to the NK-1 receptor. In competition against radiolabeled NKA, Septide also appears as a high-affinity ligand on the NK-1 receptor, with a Ki value of 1.90 ± 0.35 nM. Similarly, NKA can compete with high affinity for Septide binding on the NK-1 receptor, with a Ki value of 0.21 ± 0.01 nM.
Role in Tachykinin Receptor Actions: The finding that Septide binds with high affinity to the NK-1 receptor suggests that the NK-1 receptor may function as a general tachykinin receptor, binding subnanomolar concentrations of not only the naturally occurring neuropeptides substance P (SP) and neurokinin A (NKA), but also the synthetic peptide Septide. This observation challenges the previous notion that a special "septide receptor" or an extra NKA binding receptor might exist.
Overall, Septide is an important peptide in the study of tachykinin receptors and their functions, providing insights into the complex interactions between peptides and receptors in the nervous system.

一般情况下， Septide 多肽 粉末应该保存在-20甚至-70摄氏度. Septide 多肽 溶解后应该-70摄氏度分装保存，避免反复冻融. 了解更多细节，请查阅手册:多肽溶解及保存指南

• Hastrup H, Schwartz TW. Septide and neurokinin A are high-affinity ligands on the NK-1 receptor: evidence from homologous versus heterologous binding analysis. FEBS Lett. 1996 Dec 16;399(3):264-6. doi: 10.1016/s0014-5793(96)01337-3. PMID: 8985159.

三氟乙酸（TFA）是一种强酸，常用于从固相树脂中裂解合成的多肽，也可用于提高多肽纯化步骤中的HPLC性能。默认情况下，定制的多肽是以冻干的TFA盐的形式交付的，其中TFA的含量可能高达10-45%。

定制多肽中的TFA可能会导致后续检测数据出现无法解释的差异。例如，nM浓度的TFA已被证明会干扰细胞实验，在某些情况下会抑制细胞增殖，而在其他情况下会增加细胞活力。

TFA去除服务推荐用于:

• 将用于细胞试验的多肽
• 将被用作原料药或制成品的多肽
• 含有大量碱性残基的亲水多肽

干品多肽的重量中不仅仅包含多肽，还包含有一些非肽的组份，如水、被吸收的溶剂、配位离子和盐等。肽的净含量是指肽在其中的重量百分比，这个百分比的数值范围很大，可能从50%到90%，取决于纯度、序列以及合成和纯化的方法，不要将肽的净含量和肽的纯度混为一谈，他们是两个完全不同的概念。纯度通常是通过HPLC测定的。纯度定义的是多肽样品中含正确序列的组分的百分比，而肽的净含量是指样品中肽类物质相对于总物质所占的百分比，肽的净含量通常是氨基酸组分分析或紫外分光法测定的，这个信息主要是在一些对肽的浓度很敏感的实验中，对计算肽的浓度是很重要的。