DNA abasic site-selective enhancement of sanguinarine fluorescence with a large emission shift.
DNA abasic site-selective enhancement of sanguinarine fluorescence with a large emission shift.
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DOI：
10.1371/journal.pone.0048251
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Liu L
中科院分区：
文献类型：
--
作者：
Wu F;Sun Y;Shao Y;Xu S;Liu G;Peng J;Liu L
能够特异性结合DNA碱基位点（AP位点）的小分子由于其在DNA损伤鉴定、药物发现和传感器设计中的重要性而受到广泛关注。本文研究了天然生物碱sanguinarine （SG）的AP位点结合行为。在水溶液中，SG具有短波长的烷醇胺发射带和长波长的亚胺发射带。在pH 8.3下，SG与没有AP位点的完全匹配的dna结合时，两条条带都经历了荧光猝灭，而AP位点的存在诱导了强烈的SG结合，并且观察到的荧光增强高度依赖于AP位点两侧的核碱基，而烷醇胺条带总是猝灭。与AP位点相对的碱基对SG的排放行为也有一定的影响。研究发现，在AP位点两侧有Gs和Cs的dna的猝灭很可能是由AP位点结合的激发态SG和附近Gs之间的电子转移引起的。然而，不容易被氧化的侧翼As和Ts有利于增强发射。这种AP位点选择性的SG荧光增强伴随着从烷醇胺为主发射波段到铝波段的波段转换，因此具有约170 nm的大发射位移。吸收光谱、稳态和瞬态荧光、DNA熔化和电解质实验证实，SG的AP位点结合发生，并且与附近碱基对的堆叠相互作用可能阻止转化的SG的铝形式与水接触，因此当AP位点邻近的碱基不是鸟嘌呤时，水就会发射。我们期望该荧光团作为一种具有较大发射位移的有前途的AP位点粘合剂。
Small molecules that can specifically bind to a DNA abasic site (AP site) have received much attention due to their importance in DNA lesion identification, drug discovery, and sensor design. Herein, the AP site binding behavior of sanguinarine (SG), a natural alkaloid, was investigated. In aqueous solution, SG has a short-wavelength alkanolamine emission band and a long-wavelength iminium emission band. At pH 8.3, SG experiences a fluorescence quenching for both bands upon binding to fully matched DNAs without the AP site, while the presence of the AP site induces a strong SG binding and the observed fluorescence enhancement for the iminium band are highly dependent on the nucleobases flanking the AP site, while the alkanolamine band is always quenched. The bases opposite the AP site also exert some modifications on the SG's emission behavior. It was found that the observed quenching for DNAs with Gs and Cs flanking the AP site is most likely caused by electron transfer between the AP site-bound excited-state SG and the nearby Gs. However, the flanking As and Ts that are not easily oxidized favor the enhanced emission. This AP site-selective enhancement of SG fluorescence accompanies a band conversion in the dominate emission from the alkanolamine to iminium band thus with a large emission shift of about 170 nm. Absorption spectra, steady-state and transient-state fluorescence, DNA melting, and electrolyte experiments confirm that the AP site binding of SG occurs and the stacking interaction with the nearby base pairs is likely to prevent the converted SG iminium form from contacting with water that is thus emissive when the AP site neighbors are bases other than guanines. We expect that this fluorophore would be developed as a promising AP site binder having a large emission shift.
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影响因子：
2.6
作者：
Hossain, Maidul;Khan, Asma Yasmeen;Kumar, Gopinatha Suresh
通讯作者：
Kumar, Gopinatha Suresh
影响因子：
4.7
作者：
Buzzeo, Marisa C.;Barton, Jacqueline K.
通讯作者：
Barton, Jacqueline K.
DOI：
10.1002/jmr.300030106
发表时间：
1990-02-01
期刊：
Journal of molecular recognition : JMR
影响因子：
--
作者：
Bajaj, N P;McLean, M J;Smekal, E
通讯作者：
Smekal, E
影响因子：
5.8
作者：
Ding, ZH;Tang, SC;Liepins, A
通讯作者：
Liepins, A
影响因子：
15
作者：
Jakobsen, Ulla;Shelke, Sandip A.;Sigurdsson, Snorri Th.
通讯作者：
Sigurdsson, Snorri Th.