Perrouault L, Chassignol M, Nguyen T T, Hélène C
Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, INSERM U.201, Paris, France.
Nucleic Acids Res. 1987 Nov 11;15(21):8643-59. doi: 10.1093/nar/15.21.8643.
Oligo-heptathymidylates covalently linked to porphyrins bind to complementary sequences and can induce local damages on the target molecule. In dark reactions, iron porphyrin derivatives exhibited various chemical reactivities resulting in base oxidation, crosslinking and chain scission reactions. Reactions induced by reductants, such as ascorbic acid, dithiothreitol or mercapto-propionic acid, led to very localised reactions. A single base was the target for more than 50% of the damages. Oxidising agents such as H2O2 and its alkyl derivatives induced reactions that extended to a wider range of altered bases. The specificity of the chemical modifications observed in these systems is discussed from a mechanistic point of view.
与卟啉共价连接的寡聚七胸腺嘧啶核苷酸与互补序列结合，并可在靶分子上诱导局部损伤。在暗反应中，铁卟啉衍生物表现出各种化学反应活性，导致碱基氧化、交联和链断裂反应。由抗坏血酸、二硫苏糖醇或巯基丙酸等还原剂引发的反应导致非常局部化的反应。超过50%的损伤以单个碱基为靶点。诸如过氧化氢及其烷基衍生物等氧化剂引发的反应扩展到更广泛的碱基改变范围。从机理角度讨论了在这些系统中观察到的化学修饰的特异性。
