A conformational analysis of the (+) anti BPDE adduct to the guanine amino group of dCpdG.
A conformational analysis of the (+) anti BPDE adduct to the guanine amino group of dCpdG.
复制标题
() 抗 BPDE 加合物与 dCpdG 鸟嘌呤氨基的构象分析。
DOI：
10.1080/07391102.1983.10507492
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发表时间：
1983
影响因子：
4.4
通讯作者：
Broyde,S
中科院分区：
文献类型：
--
作者：
Hingerty,B;Broyde,S
苯并[a]芘二醇环氧化物、7-β、8-a-二羟基-9-α、10-α-环氧基-7，8，9，10-四氢苯并[a]芘的(+)对映异构体是哺乳动物体内可能的致癌物质。它与DNA在鸟嘌呤的N2处形成主要的加合物。为了在原子分辨细节上阐明其构象，对与dCpdG的加合物进行了最小构象势能计算。进行了涉及约1000个试验的全球构象搜索。最低能量构象在碳氢化合物和邻位胞苷之间有堆积，这与对改性GPU和UPG的CD研究相一致。这种构象不同于B型，最显著的是鸟嘌呤糖苷的扭转，它是高抗的。次低能量形式的扭转角类似于B形式，具有鸟嘌呤-胞苷的堆积。这两种构象的能量相差只有2.1千卡/摩尔，这表明它们的相对稳定性在较大的聚合物中或在特定的环境条件下很容易逆转。还发现了其他构象，具有碱-烃或碱-碱堆积，能量稍高。Z形在7.8千卡/摩尔。因此，该加合物稳定B型，而不是N2连接的AAF加合物，后者稳定Z构象。
The (+) anti isomer of benz[a]pyrene diol epoxide (BPDE), 7β, 8a-dihydroxy-9α,10α-epoxy- 7,8,9,10-tetrahydrobenz[a]pyrene has been identified as the probable tumorigenic lesion in mammalian systems. It forms a predominant adduct with DNA at N2of guanine. In order to elucidate its conformation in atomic resolution detail, minimized conformational potential energy calculations were performed for the adduct with dCpdG. A global conformation search involving about 1000 trials was made. The lowest energy conformation had stacking between the hydrocarbon and the adjacent cytidine, in agreement with CD studies on modified GpU and UpG. This conformer differed from the B form most notably in the guanine glycosidic torsion, which is high anti. The next lowest energy form had torsion angles like the B form, with guanine-cytidine stacking. These two conformers differ in energy by only 2.1 kcal./mole, suggesting that their relative stability could easily be reversed in larger polymers, or under specific environmental conditions. Other conformations, with base-hydrocarbon or base-base stacking are also found, at somewhat higher energies. The Z form is at 7.8 kcal./mole. Thus, this adduct stabilizes the B form, in contrast with the N2linked AAF adduct, which stabilizes the Z conformation.
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影响因子：
15
作者：
J. Kao;N. L. Allinger
通讯作者：
N. L. Allinger
通过圆二色性测量用苯并[a]芘-7,8-二氢二醇9,10-氧化物修饰的二核苷单磷酸的构象。
影响因子：
2.9
作者：
K. Frenkel;D. Grunberger;M. Boublik;I. Weinstein
通讯作者：
I. Weinstein
通过X射线晶体学测定(I-)-7,8,9,10-四羟基-7,8,9,10-四氢苯并(a)芘的分子结构。
影响因子：
11.2
作者：
S. Neidle;A. Subbiah;R. Kuroda;C. S. Cooper
通讯作者：
C. S. Cooper
用 2-(乙酰氨基)芴修饰鸟嘌呤碳 8 的脱氧二核苷单磷酸 dCpdG 的构象。
影响因子：
2.9
作者：
Hingerty,B;Broyde,S
通讯作者：
Broyde,S
影响因子：
5.1
作者：
KADLUBAR, FF
通讯作者：
KADLUBAR, FF