de Souza Pereira Helena, Leão-Ferreira Luiz Roberto, Moussatché Nissin, Teixeira Valéria Laneuville, Cavalcanti Diana Negrão, da Costa Luciana Jesus, Diaz Ricardo, Frugulhetti Izabel Christina
Departamento de Biologia Celular e Molecular/Programa de Neuroimunologia, Instituto de Biologia, Universidade Federal Fluminense, Niterói - RJ, Brasil.
Planta Med. 2005 Nov;71(11):1019-24. doi: 10.1055/s-2005-873113.
It has been recently demonstrated that HIV-1 reverse transcriptase is the target of two diterpenes, (6 R)-6-hydroxydichotoma-3,14-diene-1,17-dial (compound 1) and (6 R)-6-acetoxydichotoma-3,14-diene-1,17-dial (compound 2), that inhibit HIV-1 replication in vitro. In this work, the effects of both diterpenes on the kinetic properties of the recombinant HIV-1 reverse transcriptase (RT) enzyme were evaluated. RNA-dependent DNA-polymerase (RDDP) activity assays demonstrated that both diterpenes behave as non-competitive inhibitors with respect to dTTP and uncompetitive inhibitors with respect to poly(rA).oligo(dT) template primers. The K(i) values obtained for compounds 1 and 2 were 10 and 35 microM, respectively. Neither of these diterpenes affected the DNA-dependent DNA-polymerase (DDDP) activity of the HIV-1 RT. The RDDP activities of AMV-RT and MMLV-RT enzymes were also inhibited by compounds 1 and 2. In contrast to the HIV-1 enzyme, the DDDP activities of AMV-RT and MMLV-RT enzymes were significantly reduced by compound 1. Taken together, our results demonstrate that compound 1 is a more effective inhibitor of the viral reverse transcriptases from HIV-1, AMV and MMLV than compound 2. The kinetic behavior analyses of the HIV-1 RT demonstrate that both diterpenes have similar mechanisms of inhibition of RDDP activity.
最近有研究表明，HIV-1逆转录酶是两种二萜类化合物的作用靶点，即(6R)-6-羟基二氯托马-3,14-二烯-1,17-二醛（化合物1）和(6R)-6-乙酰氧基二氯托马-3,14-二烯-1,17-二醛（化合物2），它们在体外可抑制HIV-1复制。在本研究中，评估了这两种二萜类化合物对重组HIV-1逆转录酶（RT）酶动力学特性的影响。RNA依赖性DNA聚合酶（RDDP）活性测定表明，这两种二萜类化合物对dTTP表现为非竞争性抑制剂，对聚(rA)·寡聚(dT)模板引物表现为反竞争性抑制剂。化合物1和2的K(i)值分别为10和35微摩尔。这两种二萜类化合物均未影响HIV-1 RT的DNA依赖性DNA聚合酶（DDDP）活性。化合物1和2也抑制了禽成髓细胞瘤病毒逆转录酶（AMV-RT）和莫洛尼鼠白血病病毒逆转录酶（MMLV-RT）的RDDP活性。与HIV-1酶不同，化合物1显著降低了AMV-RT和MMLV-RT酶的DDDP活性。综上所述，我们的结果表明，与化合物2相比，化合物1是HIV-1、AMV和MMLV病毒逆转录酶更有效的抑制剂。HIV-1 RT的动力学行为分析表明，这两种二萜类化合物对RDDP活性的抑制机制相似。
