Gruber H J, Marek M, Schindler H, Kaiser K
Institute of Biophysics, J. Kepler University, Linz, Austria.
Bioconjug Chem. 1997 Jul-Aug;8(4):552-9. doi: 10.1021/bc970087m.
Conventional biotin-fluorophore conjugates with approximately 14 atom spacers lose most of their fluorescence when binding to avidin or streptavidin, as is demonstrated in the present study. This explains the unusual fact that only biotinylated marker enzymes, but not fluorescent biotins, are regularly used in bioanalytic assays. Novel biotin-spacer-fluorophore conjugates are presented that retain intense fluorescence when binding to avidin or streptavidin. Preservation of fluorescence depends upon the use of poly(ethylene glycol) (PEG) spacers, which are shown not to interfere with biotin function. The observed absence of nonspecific interactions may also be attributed to the PEG chain. These novel fluorescent biotins are expected to be excellent new tools in fluorescence microscopy and related techniques.
如本研究所示，具有约14个原子间隔臂的传统生物素-荧光团缀合物在与抗生物素蛋白或链霉抗生物素蛋白结合时会失去大部分荧光。这就解释了一个不同寻常的事实，即在生物分析测定中通常只使用生物素化的标记酶，而不使用荧光生物素。本文介绍了新型生物素-间隔臂-荧光团缀合物，它们在与抗生物素蛋白或链霉抗生物素蛋白结合时仍保留强烈荧光。荧光的保留取决于聚乙二醇（PEG）间隔臂的使用，已证明其不会干扰生物素的功能。观察到的非特异性相互作用的缺失也可能归因于PEG链。这些新型荧光生物素有望成为荧光显微镜及相关技术中出色的新工具。
