This paper describes the design of terminal-mismatch discriminating fluorescent oligonucleotides (TMDFOs). The method is based on the use of sets of oligo-2′-deoxyribonucleotide probes linked via their 5′-ends, and varying-sized flexible polymethylene chains, to thiazole orange, with the linker being attached to the benzothiazole moiety. The sequence of each set of labelled probes was identical and complementary to the sequence to be analyzed on the single-stranded nucleic acid target except at the interrogation position, located at the 5′-end of the probes in a position adjacent to the attachment site of the label, where each of the four nucleic bases were incorporated. This work allowed the selection of probes showing, upon their hybridization with the target sequence, good discrimination between the matched and the mismatched duplexes under non-stringent conditions, with the mismatched duplexes being more fluorescent than the perfectly matched ones.
本文描述了终端不匹配识别荧光寡核苷酸(TMDFOs)的设计。该方法基于使用一组通过其5′末端连接的寡2′-脱氧
核糖核苷探针,以及与
噻唑橙连接的不同大小的柔性聚亚甲基链,连接器则附着在苯
噻唑部分。每组标记探针的序列是相同的,并且与要分析的单链核酸靶序列互补,唯一区别在于探针5′端的查询位置,该位置邻近标签的结合位点,四种核苷基在此处各自被引入。该工作使得能够选择在与靶序列杂交时,能够在非严格条件下良好区分匹配和不匹配的双链结构的探针,其中不匹配的双链比完美匹配的更具荧光性。