Institute of Virology, Charité Universitätsmedizin Berlin, Berlin, Germany.
Antimicrob Agents Chemother. 2009 Dec;53(12):5095-101. doi: 10.1128/AAC.00809-09. Epub 2009 Sep 28.
Recently we characterized two inhibitors targeting the human cytomegalovirus (HCMV) terminase, 2-bromo-4,5,6-trichloro-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl) benzimidazole (BTCRB) and 2,4,5,6-tetrachloro-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl) benzimidazole (Cl(4)RB). The terminase consists of the ATP-hydrolyzing subunit pUL56 and the subunit pUL89 required for duplex nicking. Because mammalian cell DNA replication does not involve cleavage of concatemeric DNA by a terminase, these compounds represent attractive alternative HCMV antivirals. We now have tested these previously identified benzimidazole ribonucleosides in order to determine if they are active against HCMV clinical isolates as well as those of herpes simplex virus type 1, mouse cytomegalovirus, rat cytomegalovirus (RCMV), and varicella-zoster virus (VZV). Antiviral activity was quantified by measurement of viral plaque formation (plaque reduction) and by viral growth kinetics. Interestingly, both BTCRB and Cl(4)RB had an inhibitory effect in ganciclovir (GCV)-sensitive and GCV-resistant clinical isolates, with the best effect produced by Cl(4)RB. Electron microscopy revealed that in cells infected with GCV-sensitive or GCV-resistant isolates, B capsids and dense bodies were formed mainly. Furthermore, pulsed-field gel electrophoresis showed that cleavage of concatenated DNA was inhibited in clinical isolates. In addition, the antiviral effect on other herpesviruses was determined. Interestingly, in plaque reduction assays, BTCRB was active against all tested herpesviruses. The best effects were observed on VZV- and RCMV-infected cells. These results demonstrate that the new compounds are highly active against GCV-resistant and GCV-sensitive clinical isolates and slightly active against other herpesviruses.
最近，我们对两种靶向人类巨细胞病毒（HCMV）末端酶的抑制剂进行了研究，这两种抑制剂分别是 2-溴-4,5,6-三氯-1-(2,3,5-三-O-乙酰基-β-D-核糖呋喃基)苯并咪唑（BTCRB）和 2,4,5,6-四氯-1-(2,3,5-三-O-乙酰基-β-D-核糖呋喃基)苯并咪唑（Cl(4)RB）。末端酶由 ATP 水解亚基 pUL56 和双链断裂所需的亚基 pUL89 组成。由于哺乳动物细胞的 DNA 复制不涉及末端酶对连接酶 DNA 的切割，因此这些化合物是有吸引力的替代 HCMV 抗病毒药物。我们现在已经测试了这些之前鉴定的苯并咪唑核糖核苷，以确定它们是否对 HCMV 临床分离株以及单纯疱疹病毒 1 型、鼠巨细胞病毒、大鼠巨细胞病毒（RCMV）和水痘带状疱疹病毒（VZV）具有活性。抗病毒活性通过测量病毒斑形成（斑减少）和病毒生长动力学来定量。有趣的是，BTCRB 和 Cl(4)RB 对更昔洛韦（GCV）敏感和 GCV 耐药的临床分离株均具有抑制作用，其中 Cl(4)RB 的效果最好。电子显微镜显示，在感染 GCV 敏感或 GCV 耐药分离株的细胞中，主要形成 B 衣壳和致密体。此外，脉冲场凝胶电泳显示，连接酶 DNA 的切割在临床分离株中受到抑制。此外，还确定了对其他疱疹病毒的抗病毒作用。有趣的是，在斑减少测定中，BTCRB 对所有测试的疱疹病毒均具有活性。在感染 VZV 和 RCMV 的细胞中观察到最佳效果。这些结果表明，新化合物对 GCV 敏感和 GCV 耐药的临床分离株具有高度活性，对其他疱疹病毒也有一定活性。
