Synthesis of undecagold cluster molecules as biochemical labeling reagents. 3. Dimeric cluster with a single reactive amino group.
Synthesis of undecagold cluster molecules as biochemical labeling reagents. 3. Dimeric cluster with a single reactive amino group.
复制标题
作为生化标记试剂的十一金簇分子的合成。
DOI：
10.1021/bi00312a011
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
Frey,PA
中科院分区：
文献类型：
--
作者：
Yang,H;Frey,PA
Heechung Yang和佩里A. Frey * 摘要：本文报道了一个十一金环簇合物Auu（CN）_3 [P-（C_6H_4CH_2NH_2）_3]_7，1的二聚衍生物的合成和表征。二聚体2由1的交联分子组成，其中42个氨基中的41个被酰化，每个二聚体留下单个游离氨基。该氨基具有反应活性，可用于制备2的衍生物，用于标记生物大分子，为电子显微镜分析做准备。在水溶液中用1.3当量柠康酸酐对1进行有限酰化，然后在pH 7 - 7.5下用乙酸酐进行广泛酰化，得到单体和二聚体产物的混合物。在pH 3.2下水解除去N-柠康酰基暴露了一些氨基。阳离子交换色谱法在pH 7分离的产品分为三个主要群体，物种含有一个，两个或三个游离氨基，在33%，28%，和15%，分别总产率。单氨基物质主要由2和单体产物组成，其通过凝胶排阻色谱法分离。2在十二烷基硫酸钠中聚丙烯酰胺凝胶电泳时作为二聚体迁移，并且它含有单个游离氨基，可通过其在pH 7下作为单价阳离子的离子交换行为以及其与[14C]邻苯二甲酸酐的反应性检测。e先前的论文（Reardon和Frey，1984; Yang等人，1984）描述了含有单个反应性羧基、活化羧基、单个反应性氨基或单个烷基化官能团如溴乙酰基或马来酰亚胺基团的十一金属簇络合物的合成。由母体化合物Aun（CN）_3 [P（C_6H_4CH_2NH_2）_3]_7，1，1合成的这些试剂可用于电子显微镜制备中复杂生化结构的蛋白质的共价标记。母体化合物及其衍生物可以通过扫描透射电子显微镜观察（Wall等人，1982; Safer等人，1982年）。一个复杂的较大的尺寸与更大的电子散射电位可能是有用的专门应用或可能为低剂量的常规透射电子显微镜。一个专门的应用程序可能涉及复杂结构中的一个组件的特定标签1和另一个组件的更大的集群。扫描透射电子显微镜可以区分两种标记物，从而提供标记位点之间的结构关系信息。一个更大的结构在低剂量常规透射电子显微镜中也可能是有用的。
Heechung Yang and Perry A. Frey* abstract: The synthesis and characterization of a dimeric derivative of the undecagold cluster complex Auu (CN) 3 [P-(C6H4CH2NH2) 3] 7, 1, are described. The dimer, 2, consists of cross-linked molecules of 1 in which 41 of the 42 amino groups are acylated, leaving a single free amino group per dimer. This amino group is reactive and can be used to prepare derivatives of 2 for use in labeling biological macromolecules in preparation for electron microscopic analysis. Limited acylation of 1 by 1.3 equiv of citraconicanhydride in aqueous solution, followed by extensive acylation with acetic anhydride at pH 7-7.5, leads to a mixture of monomeric and dimeric products. Hydrolytic removal of TV-citraconyl groups at pH 3.2 unmasks a few amino groups. Cation-exchange chromatography at pH 7 separates the products into three main groups, species containing one, two, or three free amino groups, in overall yields of 33%, 28%, and 15%, respectively. The monoamino species consist mainly of 2 and a monomeric product, which are separated by gel exclusion chromatography. 2 migrates as a dimer upon polyacrylamide gel electrophoresis in sodium dodecyl sulfate, and it contains a single free amino group, detectable by its ion-exchange behavior as a monocation at pH 7 and by its reactivity with [14C] phthalic anhydride. e preceding papers (Reardon & Frey, 1984; Yang et al., 1984) describe syntheses of undecagold cluster complexes that contain a single reactive carboxyl group, an activated carboxyl group, a single reactive amino group, or a single alkylating functional groupsuch as the bromoacetyl or maleimide groups. These reagents, synthesized from the parent compound Aun (CN) 3 [P (C6H4CH2NH2) 3] 7, l, 1 can be used for covalently labeling proteins in complex biochemical structures in prep-aration for electron microscopy. The parent compound and its derivatives can be visualized by scanning transmission electron microscopy (Wall et al., 1982; Safer et al., 1982). A complex of larger size with greater electron scattering potential could be useful for specialized applications or possibly for low-dose conventional transmission electron microscopy. A specialized applicationmight involve specific labeling of one component in a complex structurewith 1 and another component with a larger cluster. Scanning transmission electron microscopy could distinguish the two labels and thereby give information aboutthe structural re-lationships between the labeled sites. A larger structure might also be usefulin low-dose conventional transmission electron microscopy.