Ono K, Nakane H
Laboratory of Viral Oncology, Aichi Cancer Center Research Institute.
J Biochem. 1990 Oct;108(4):609-13. doi: 10.1093/oxfordjournals.jbchem.a123251.
Four flavonoids (i.e., baicalein, quercetin, quercetagetin, and myricetin), known to be inhibitors of HIV-reverse transcriptase, have been shown to be more or less inhibitory to the activities of various cellular DNA and RNA polymerases. The degree of the inhibition varied depending on the combination of the flavonoid and the enzyme species: baicalein was moderately inhibitory to DNA polymerase gamma and E. coli DNA polymerase I; quercetin was strongly inhibitory to DNA polymerase beta and E. coli RNA polymerase and moderately inhibitory to DNA polymerase I; quercetagetin was a potent inhibitor for all of DNA polymerases alpha, beta, gamma, and I and RNA polymerase; myricetin was a strong inhibitor of DNA polymerases alpha and I and RNA polymerase. However, terminal deoxynucleotidyltransferase was virtually insensitive to inhibition by these flavonoids. The inhibition by the flavonoids was due to competition with the template.primer in the case of the DNA polymerases, whereas the inhibition was due to competition with the triphosphate substrate (GTP) in the case of RNA polymerase. The Ki values of these flavonoid inhibitors for DNA and RNA polymerases was determined.
四种黄酮类化合物（即黄芩素、槲皮素、金合欢素和杨梅素），已知是HIV逆转录酶的抑制剂，已显示或多或少对各种细胞DNA和RNA聚合酶的活性具有抑制作用。抑制程度因黄酮类化合物和酶种类的组合而异：黄芩素对DNA聚合酶γ和大肠杆菌DNA聚合酶I有中度抑制作用；槲皮素对DNA聚合酶β和大肠杆菌RNA聚合酶有强烈抑制作用，对DNA聚合酶I有中度抑制作用；金合欢素对所有DNA聚合酶α、β、γ和I以及RNA聚合酶都是强效抑制剂；杨梅素是DNA聚合酶α和I以及RNA聚合酶的强抑制剂。然而，末端脱氧核苷酸转移酶实际上对这些黄酮类化合物的抑制不敏感。黄酮类化合物的抑制作用在DNA聚合酶的情况下是由于与模板引物竞争，而在RNA聚合酶的情况下是由于与三磷酸底物（GTP）竞争。测定了这些黄酮类抑制剂对DNA和RNA聚合酶的Ki值。
