Sastry S S, Spielmann H P, Dwyer T J, Wemmer D E, Hearst J E
Department of Chemistry, University of California, Berkeley.
J Photochem Photobiol B. 1992 Jun 30;14(1-2):65-79. doi: 10.1016/1011-1344(92)85083-7.
We have developed novel methods for the preparation of multimicromole quantities of extremely pure, uniquely photoadducted psoralen-DNA cross-links, furan-side monoadducted DNA and pyrone-side monoadducts. Psoralen cross-linked and furan-side monoadducted DNA were produced by employing high intensity argon ion and krypton ion lasers as light sources. Pyrone-side monoadducts were prepared by base-catalyzed photoreversal of psoralen cross-links. The various psoralen-adducted DNA oligomers were efficiently purified by high performance liquid chromatography. These methods have permitted us to synthesize 4 mumol each of a self-complementary 8-mer d(GCGTACGC) 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen (HMT) furan-side monoadduct and HMT cross-link. Preliminary nuclear magnetic resonance (NMR) data on the HMT cross-linked 8-mer d(GCGTACGC) have been obtained which confirmed the presence of the diadducted psoralen at the unique 5'TpA3' site. NMR data obtained from the 8-mer furan-side monoadduct revealed that the psoralen molecule is intercalated into the DNA double helix. Preliminary crystals of 8-mer cross-linked DNA molecule have been grown. Conditions for the growth of X-ray diffraction-quality crystals and the further analysis of these crystals are now in progress.
我们已经开发出了新方法，可制备多微摩尔量的极其纯净、具有独特光加合作用的补骨脂素 - DNA交联物、呋喃侧单加合DNA和吡喃酮侧单加合物。补骨脂素交联的和呋喃侧单加合的DNA是通过使用高强度氩离子激光和氪离子激光作为光源产生的。吡喃酮侧单加合物是通过补骨脂素交联物的碱催化光逆转制备的。各种补骨脂素加合的DNA寡聚物通过高效液相色谱法得到了有效纯化。这些方法使我们能够合成4 μmol的自互补8聚体d(GCGTACGC) 4'-(羟甲基)-4,5',8-三甲基补骨脂素（HMT）呋喃侧单加合物和HMT交联物各4 μmol。已获得关于HMT交联的8聚体d(GCGTACGC)的初步核磁共振（NMR）数据，证实了在独特的5'TpA3'位点存在双加合补骨脂素。从8聚体呋喃侧单加合物获得的NMR数据表明补骨脂素分子插入到了DNA双螺旋中。已培养出8聚体交联DNA分子的初步晶体。目前正在进行用于生长X射线衍射质量晶体的条件以及对这些晶体的进一步分析。
