Processes are disclosed that use 3′-reversibly terminated nucleoside triphosphates to analyze DNA for purposes other than sequencing using cyclic reversible termination. These processes are based on the unexpected ability of terminal transferase to accept these triphosphates as substrates, the unexpected ability of polymerases to add reversibly and irreversibly terminated triphosphates in competition with each other, the development of cleavage conditions to remove the terminating group rapidly, in high yield, and without substantial damage to the terminated oligonucleotide product, and the ability of reversibly terminated primer extension products to capture groups. The presently preferred embodiments of the disclosed processes use a triphosphate having its 3′-OH group blocked as a 3′-ONH2 group, which can be removed in buffered NaNO2 and use variants of Taq DNA polymerase, including one that has a replacement (L616A).
披露了使用3'-可逆终止核苷酸
三磷酸盐来分析DNA的过程,用于除了使用循环可逆终止以外的目的。这些过程基于末端转移酶接受这些
三磷酸盐作为底物的意外能力,聚合酶与可逆和不可逆终止的
三磷酸盐相互竞争添加的意外能力,开发了裂解条件以快速去除终止基团,在高产率下且不会对终止寡核苷酸产物造成重大损害,以及可逆终止引物延伸产物捕获基团的能力。目前披露的过程的首选实施方式使用一个其3'-OH基团被阻断为3'-ONH2基团的
三磷酸盐,在缓冲NaNO2中可以被去除,并使用Taq
DNA聚合酶的变体,包括一个具有替换(L616A)的变体。