思文霉素抑制核酸合成机理初探

Preliminary Mechanism Studies of Siwenmycin on the Inhibition of Nucleic Acid Syntheses

本文以光谱法,DNA琼脂糖电泳及酶学方法等技术观察思文霉素(Siwenmycin)与DNA的相互作用和对核酸合成相关酶的影响。结果表明,思文霉素对DNA可产生直接嵌合作用,但它对DNA多聚酶Ⅰ和T_7RNA多聚酶均无明显抑制作用,说明思文霉素对核酸合成的抑制作用并非由于直接损伤了DNA模板所致。

Siwenmycin, isolated from astreptomyces culture, is a new member ofaclacinomycin analogues. It exhibited aremarkable inhibitory effect on the bio-synthesis of DNA and RNA in vivo. Inorder to recognize the mechanism of theinhibitions, the reactions of siwenmycinto DNA template, DNA polymerase I andRNA polymerase were studied. Experi-mental results showed that siwenmycincould intercalate DNA, but it did notinhibit DNA polymerase I-mediated DNArepair replication and T_7 RNA polymerase-mediated DNA transcription. This indi-cates that siwenmycin is not a damage tothe DNA template function, nor will itinhibit DNA polymerase I and T_7RNApolymerase, though it can intercalateDNA.