Eriksson Maja, Westerlund Fredrik, Mehmedovic Merima, Lincoln Per, Westman Gunnar, Larsson Anette, Akerman Björn
Department of Chemical and Biological Engineering, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
Biophys Chem. 2006 Aug 1;122(3):195-205. doi: 10.1016/j.bpc.2006.03.009. Epub 2006 Mar 24.
The unsymmetrical cyanine dyes BOXTO-PRO and BOXTO-MEE were derived from the DNA groove binder BOXTO, by adding a positively charged or a non-ionic hydrophilic tail to BOXTO, respectively. The main objective was to obtain more efficient DNA probes, for instance in electrophoresis and microscopy, by slowing down the dissociation of BOXTO from DNA. The interactions with mixed sequence DNA was studied with fluorescence and absorbance spectroscopy, stopped-flow dissociation and gel electrophoresis. Both the derivatives are groove bound as BOXTO, and have similar fluorescence properties when bound to mixed sequence DNA in free solution. BOXTO-PRO exhibits a slower dissociation than BOXTO from DNA, whereas the dissociation rate for BOXTO-MEE is faster and, unexpectedly independent of the ionic strength. During gel electrophoresis both BOXTO-PRO and BOXTO-MEE exhibit a faster dissociation rate than BOXTO. Still, BOXTO-PRO seems to be a good alternative as DNA probe, especially for applications in free solution where the dissociation is slower than for the corresponding intercalator TOPRO-1.
不对称花青染料BOXTO - PRO和BOXTO - MEE分别是由DNA沟结合剂BOXTO衍生而来，通过向BOXTO分别添加带正电荷的或非离子亲水头尾。主要目的是通过减缓BOXTO从DNA上的解离来获得更高效的DNA探针，例如在电泳和显微镜检查中。通过荧光和吸收光谱、停流解离和凝胶电泳研究了与混合序列DNA的相互作用。两种衍生物都像BOXTO一样结合在沟中，并且在游离溶液中与混合序列DNA结合时具有相似的荧光特性。BOXTO - PRO从DNA上的解离比BOXTO慢，而BOXTO - MEE的解离速率更快，并且出乎意料地与离子强度无关。在凝胶电泳过程中，BOXTO - PRO和BOXTO - MEE的解离速率都比BOXTO快。尽管如此，BOXTO - PRO似乎是一种很好的DNA探针替代品，特别是在游离溶液中的应用，其解离比相应的嵌入剂TOPRO - 1慢。
