GPAnt-2 多肽

Pyr-QwFwwM-NH2, w=D-Trp

pGlu-Gln-D-Trp-Phe-D-Trp-D-Trp-Met-NH2

7

95.22

C₅₇H₆₄N₁₂O₉S

1093.25

143675-79-0

71308571

固相合成

GPAnt-2, has the amino acid sequence pGlu-Gln-D-Trp-Phe-D-Trp-D-Trp-Met-NH2, is a G-Protein antagonist peptide.
GPAnt-2 inhibited the activation of G proteins (Gi or Go) by M2 muscarinic cholinergic receptor (M2 mAChR) or of Gs by β-adrenergic receptor in the reconstituted phospholipid vesicles, as measured by receptor-promoted GTP hydrolysis.
The inhibition by GPAnt-2 was apparently reversible and competitive with respect to receptor binding to G proteins. The inhibition could be overcome by increasing the concentration of receptor in the vesicles and was not altered by changes in the concentration of G protein, suggesting that the peptide competes with the receptor for interaction with G proteins.
GPAnt-2 did not interfere with the binding of ligands to the receptor or the interaction of G protein and guanine nucleotide.
GPAnt-2 can be used as a tool to study the receptor-G protein interaction. For example, it was used to analyze the effect of an agonist on receptor-G protein coupling, and the results suggested that an agonist enhances the productive interaction between receptor and G protein by increasing the efficacy of coupling, not by increasing the affinity between receptor and G protein.

一般情况下， GPAnt-2 多肽 粉末应该保存在-20甚至-70摄氏度. GPAnt-2 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

• Mukai H, Munekata E, Higashijima T. G protein antagonists. A novel hydrophobic peptide competes with receptor for G protein binding. J Biol Chem. 1992 Aug 15;267(23):16237-43. PMID: 1379592.

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。