DNA的维持与脱嘌呤位点的修复。

Maintenance of DNA and repair of Apurinic sites.

作者信息

Verly W G

出版信息

Basic Life Sci. 1975;5A:39-46. doi: 10.1007/978-1-4684-2895-7_6.

PMID:172058

Abstract

Escherichia coli cells contain an enzyme which hydrolyzes a phosphodiester bond near each apurinic site in double-stranded DNA. This endonuclease is specific for apurinic sites; it has no effect on normal DNA, and its action on alkylated DNA is restricted to apurinic sites. In vitro incubation with the endonuclease for apurinic sites, DNA polymerase I, and ligase permits repair of DNA containing apurinic sites. The endonuclease for apurinic sites might thus play a role in cell survival after a treatment with alkylating agents; as DNA spontaneously loses purines, the enzyme might also play a role in the maintance of a normal DNA in every cell. Indeed, an endonuclease for apurinic sites has been found not only in bacteria but also in animal and plant cells; it is very active in thermophilic bacteria.

摘要

大肠杆菌细胞含有一种酶，该酶可水解双链DNA中每个脱嘌呤位点附近的磷酸二酯键。这种内切核酸酶对脱嘌呤位点具有特异性；它对正常DNA没有影响，并且其对烷基化DNA的作用仅限于脱嘌呤位点。用脱嘌呤位点内切核酸酶、DNA聚合酶I和连接酶进行体外孵育可修复含有脱嘌呤位点的DNA。因此，脱嘌呤位点内切核酸酶可能在烷基化剂处理后的细胞存活中发挥作用；由于DNA会自发丢失嘌呤，该酶也可能在维持每个细胞中的正常DNA方面发挥作用。事实上，不仅在细菌中，而且在动植物细胞中都发现了脱嘌呤位点内切核酸酶；它在嗜热细菌中非常活跃。