RESISTANCE TO 1-[(2-HYDROXYETHOXY)METHYL]-6-(PHENYLTHIO)THYMINE DERIVATIVES IS GENERATED BY MUTATIONS AT MULTIPLE SITES IN THE HIV-1 REVERSE-TRANSCRIPTASE
RESISTANCE TO 1-[(2-HYDROXYETHOXY)METHYL]-6-(PHENYLTHIO)THYMINE DERIVATIVES IS GENERATED BY MUTATIONS AT MULTIPLE SITES IN THE HIV-1 REVERSE-TRANSCRIPTASE
复制标题
DOI：
10.1006/viro.1995.1330
复制
发表时间：
1995-06-20
期刊：
影响因子：
3.7
通讯作者：
BADER, JP
中科院分区：
文献类型：
--
作者：
BUCKHEIT, RW;FLIAKASBOLTZ, V;BADER, JP
在细胞培养物中选择对1-[（2-羟基乙氧基）甲基]-6-（苯硫基）胸腺嘧啶（HEPT）和高效HEPT衍生物[1-苄氧基甲基-5-乙基-6-（α-吡啶硫基）尿嘧啶]（NSC 648400，E-BPTU）具有抗性的病毒分离株。交叉耐药性评价表明，这两种耐药病毒分离株的表型彼此不同，尽管每种病毒分离株对两种HEPT衍生物均具有耐药性。对NSC 648400耐药的病毒分离株逆转录酶（Y181 C）中有一个氨基酸变化，导致对所有评价的非核苷类逆转录酶抑制剂产生交叉耐药性，但钙铝榴石A除外。NSC 648400-抗性病毒分离株表现出15倍增强的对卡兰布曲酶A的敏感性。在HEPT存在下选择的病毒分离株表现出单一氨基酸变化（P236 L），除了两种HEPT衍生物之外，其对测试的其他非核苷RT抑制剂没有交叉抗性。这种HEPT耐药病毒分离株对噻唑并苯并咪唑的敏感性增强（5- 10倍）。我们使用了RT中具有确定的单个氨基酸变化的病毒分离株和具有定点氨基酸取代的细菌表达的RT，以测试各种突变对NSC 648400活性的影响。在氨基酸101、103、106、181或236处的单突变产生对NSC 648400具有高抗性（> 20倍）的病毒，而在氨基酸98、100或108处的突变中观察到较低水平的抗性。这些结果表明，HIV-1逆转录酶的非核苷抑制剂结合位点的构象的几个变化可以影响HEPT类化合物的抑制活性。(C)1995学术出版社，Inc.
Virus isolates resistant to 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) and a highly potent HEPT derivative, [1-benzyloxymethyl-5-ethyl-6-(alpha-pyridylthio)uracil] (NSC 648400, E-BPTU), were selected in cell culture. Cross-resistance evaluation indicated that the two drug-resistant virus isolates were phenotypically distinct from one another although each of the virus isolates was resistant to both of the HEPT derivatives. The virus isolate resistant to NSC 648400 had a single amino acid change in the reverse transcriptase (Y181C) which resulted in cross-resistance to all of the nonnucleoside reverse transcriptase inhibitors evaluated, with the exception of calanolide A. The NSC 648400-resistant virus isolate exhibited 15-fold enhanced sensitivity to calanolide A. The virus isolate selected in the presence of HEPT exhibited a single amino acid change (P236L) which was not cross-resistant to other nonnucleoside RT inhibitors tested with the exception of the two HEPT derivatives. This HEPT-resistant virus isolate exhibited enhanced sensitivity (5- to 10-fold) to thiazolobenzimidazole. We have used both virus isolates with defined single amino acid changes in the RT and bacterially expressed RTs with site-directed amino acid substitutions to test the effects of a wide variety of mutations on the activity of NSC 648400. Single mutations at amino acids 101, 103, 106, 181, or 236 yielded virus with high resistance (> 20)-fold) to NSC 648400, while lower levels of resistance were seen with mutations at amino acids 98, 100, or 108. These results suggest that several changes in the conformation of the nonnucleoside inhibitor binding site of the HIV-1 reverse transcriptase can affect the inhibitory activity of the HEPT class of compounds. (C) 1995 academic Press, Inc.