摘要： 限制性内切核酸酶的切割识别序列分为回纹对称和非回纹对称结构两类，由于DNA是互补双链， 所以对于识别序列为回纹对称结构的限制酶，其识别序列在DNA的两条链上是一致的， 可以写为一个， 但对于识别序列为非回纹对称结构的限制酶来说，其识别序列应为两个，而一些工具书、参考书中仅写为一个。本文通过一个酶切实验证明其识别序列为两个。同时希望通过本文，敦促一些工具书、参考书更正其错误。
Abstract:The recognizing sequence of restriction enzyme includes palindrome and nonpalindromic,and DNA is double helix complementary strands.So the recognizing sequences of palindrome enzyme in two strands of DNA were identical,and can be considered of one sequence.But for nonpalindromic restriction enzyme,the recognizing sequences of two strands of DNA were not identical.Therefore the true recognizing sequences are not only one.In this experiment,an enzyme cleavage reaction was carried out which confirmed that the true recognizing sites/sequences of nonpalindromic enzyme are two instead of one.