Visualizing the Molecular Interactions of a Nucleotide Analog, GS-9148, with HIV-1 Reverse Transcriptase-DNA Complex
Visualizing the Molecular Interactions of a Nucleotide Analog, GS-9148, with HIV-1 Reverse Transcriptase-DNA Complex
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DOI：
10.1016/j.jmb.2010.02.019
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发表时间：
2010-04-09
影响因子：
5.6
通讯作者：
Swaminathan, S.
中科院分区：
文献类型：
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作者：
Lansdon, Eric B.;Samuel, Dharmaraj;Swaminathan, S.
GS-9148HIV酸)是一种潮湿的(2‘-脱氧腺苷一磷酸)类似物，可保持其对抗药性([5-(6-amino-purin-9-yl)-4-fluoro-2，5-dihydro-furan-2-yloxy-methyl]phosphonic的抗病毒活性。获得了HIV-1逆转录酶(RT)与双链DNA结合的晶体结构，与GS-9148-二磷酸或2‘-脱氧三磷酸(DATP)的三元络合物，以及与GS-9148移位到启动位点的掺入后结构，以深入了解RT抑制的机制。GS-9148-二磷酸或dATP与二元RT DNA复合体的结合导致FING亚域关闭在传入底物周围。当手指亚域向手掌和拇指亚域关闭时，这产生了高达9A的移位。GS-9148-二磷酸在核苷酸结合部位表现出与dATP相似的结合模式。突变导致对核苷酸/核苷RT抑制剂(如M184、Y115、L74和K65)产生抗药性的残基，无论是GS-9148-二磷酸还是dATP结合，其取向都几乎没有改变。结合中观察到的一个不同之处是中心环的位置。GS-9148-二磷酸的二氢呋喃环与Y115的芳香族侧链的相互作用大于dATP的核糖环，可能获得了有利的相互作用。GS-9148-二磷酸模拟dATP活性部位接触的能力可能解释了它对RT的有效抑制和对耐药突变的保持活性。有趣的是，GS-9148-二磷酸的2‘-氟部分被发现在Q151侧链附近，这可能解释了Q151M突变导致GS-9148中等程度降低的原因。(C)2010爱思唯尔有限公司。保留所有权利。
GS-9148 ([5-(6-amino-purin-9-yl)-4-fluoro-2,5-dihydro-furan-2-yloxy-methyl]phosphonic acid) is a dAMP (2'-deoxyadenosine monophosphate) analog that maintains its antiviral activity against drug-resistant HIV. Crystal structures for HIV-1 reverse transcriptase (RT) bound to double-stranded DNA, ternary complexes with either GS-9148-diphosphate or 2'-deoxyadenosine triphosphate (dATP), and a post-incorporation structure with GS-9148 translocated to the priming site were obtained to gain insight into the mechanism of RT inhibition. The binding of either GS-9148-diphosphate or dATP to the binary RT DNA complex resulted in the fingers subdomain closing around the incoming substrate. This produced up to a 9 A shift in the tips of the fingers subdomain as it closed toward the palm and thumb subdomains. GS-9148-diphosphate shows a similar binding mode as dATP in the nucleotide-binding site. Residues whose mutations confer resistance to nucleotide/nucleoside RT inhibitors, such as M184, Y115, L74, and K65, show little to no shift in orientation whether GS-9148-diphosphate or dATP is bound. One difference observed in binding is the position of the central ring. The dihydrofuran ring of GS-9148-diphosphate interacts with the aromatic side chain of Y115 more than does the ribose ring of dATP, possibly picking up a favorable it it interaction. The ability of GS-9148-diphosphate to mimic the active-site contacts of dATP may explain its effective inhibition of RT and maintained activity against resistance mutations. Interestingly, the 2'-fluoro moiety of GS-9148-diphosphate was found in close proximity to the Q151 side chain, potentially explaining the observed moderately reduced susceptibly to GS-9148 conferred by Q151M mutation. (C) 2010 Elsevier Ltd. All rights reserved.