A novel artificial nucleic acid base pair which is obtained by forming a selective base pair by introducing a group having steric hindrance (preferably a group having steric hindrance and static repulsion and a stacking effect) and can be recognized by a polymerase such as DNA polymerase; a novel artificial gene; and a method of designing nucleic acid bases so as to form a selective base pair with the use of steric hindrance, static repulsion and stacking effect at the base moiety of the nucleic acid. An artificial nucleic acid comprising these bases; a process for producing the same; a codon containing the same; a nucleic acid molecule containing the same; a process for producing a non-natural gene by using the same; a process for producing a novel protein by using the above nucleic acid molecule or non-natural gene, and the like.
一种新型人工核酸碱基对,通过引入具有立体位阻(优选为具有立体位阻和静电斥力以及堆积效应)的基团形成选择性碱基对,并且可以被聚合酶如
DNA聚合酶识别;一种新型人工
基因;以及一种设计核酸碱基的方法,以便在核酸的碱基部分利用立体位阻、静电斥力和堆积效应形成选择性碱基对。包含这些碱基的人工核酸;制备该人工核酸的方法;包含该人工核酸的密码子;包含该人工核酸的核酸分子;使用该人工核酸制备非天然
基因的方法;使用上述核酸分子或非天然
基因制备新型蛋白质的方法等。