Taylor J M, Jacob-Mosier G G, Lawton R G, Neubig R R
Department of Pharmacology, University of Michigan, Ann Arbor 48109.
Peptides. 1994;15(5):829-34. doi: 10.1016/0196-9781(94)90038-8.
A photoreactive derivative of a tetradecapeptide G-protein activator (peptide Q) derived from the alpha 2-adrenergic receptor was designed and used to label purified G-protein (Go/Gi). N-bromoacetyl-N'-(3-diazopyruvoyl)-m-phenylene-diamine (Br-DAP) was conjugated to the C-terminal cysteine of peptide Q. The DAP-modified peptide Q (DAP-Q) specifically incorporated into the a subunit of Go. The incorporation of DAP-Q into alpha o was blocked by unmodified Q peptide (IC50 = 15 +/- 6 microM; n = 4). Photolysis of sixfold higher concentrations of DAP-Q with ovalbumin or bovine albumin failed to produce cross-linked products. Br-DAP should prove useful in detecting mutual contact sites between peptides and their binding proteins.
设计并使用了一种源自α2-肾上腺素能受体的十四肽G蛋白激活剂（肽Q）的光反应性衍生物来标记纯化的G蛋白（Go/Gi）。N-溴乙酰基-N'-（3-重氮丙酮酰基）-间苯二胺（Br-DAP）与肽Q的C端半胱氨酸偶联。DAP修饰的肽Q（DAP-Q）特异性地掺入Go的α亚基中。未修饰的Q肽可阻断DAP-Q掺入αo（IC50 = 15 +/- 6 microM；n = 4）。用卵清蛋白或牛血清白蛋白对浓度高六倍的DAP-Q进行光解未能产生交联产物。Br-DAP在检测肽与其结合蛋白之间的相互接触位点方面应会很有用。
