Effects of deficient of the Hoogsteen base-pairs on the G-quadruplex stabilization and binding mode of a cationic porphyrin
| العنوان: | Effects of deficient of the Hoogsteen base-pairs on the G-quadruplex stabilization and binding mode of a cationic porphyrin |
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| المؤلفون: | Da Young Kim, Jihye Moon, Seog K. Kim, Ji Hoon Han, Maeng-Joon Jung |
| المصدر: | Biochemistry and Biophysics Reports |
| بيانات النشر: | Elsevier BV, 2015. |
| سنة النشر: | 2015 |
| مصطلحات موضوعية: | Circular dichroism, G-quadruplex, Chemistry, Hydrogen bond, Guanine, Stereochemistry, Cationic porphyrin, Hoogsteen base pair, Biophysics, Hoogsteen base pairing, Triple-stranded DNA, DNA, Biochemistry, Porphyrin, chemistry.chemical_compound, Thermal stability, Thermal melting curve, Research Article |
| الوصف: | Background In stabilization of the G-quadruplex, formation of a Hoogsteen base-pair between the guanine (G) bases is essential. However, the contribution of each Hoogsteen base-pair at different positions to whole stability of the G-quadruplex has not been known. In this study, the effect of a deficiency of the Hoogsteen type hydrogen bond in the G-quadruplex stability was investigated. Spectral properties of meso-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP) associated with various G-quadruplexes were also examined. Methods The thermal stability of the thrombin-binding DNA aptamer 5′G1G2TTG5G6TG8TG10G11TTG14G15 G-quadruplex, in which the guanine (G) base at 1, 2, 5, 6 and 8th positions was replaced with an inosine (I) base, one at a time, was investigated by circular dichroism (CD). The absorption, CD and fluorescence decay curve for the G-quadruplex associated TMPyP were also measured. Results The transition from the G-quadruplex to a single stranded form was endothermic and induced by an increase in entropy. The order in stability was 0>8>6>2>5>1, where the numbers denote the position of the replacement and 0 represents no replacements of the G base, suggesting the significant contribution of the G1 base in the stability of the G-quadruplex. Alteration in the spectral property of TMPyP briefly followed the order in thermal stability. Conclusions Replacement of a G base with an I base resulted in destabilization of the G-quadruplex. The missing hydrogen bond at position 1 destabilized the G-quadruplex most efficiently. TMPyP binds near the I base-replaced location namely, the side of the G-quadruplex. General significance The Hoogsteen base-pairing is confirmed to be essential in stabilization of G-quadruplex. When G is replaced with I, the latter base is mobile to interact with cationic porphyrin. Graphical abstract Highlights • Thermal stability of a quadruplex, 5´G1G2TTG5G6TG8TG9G10TTG11G12 was investigated. • Replacement of G by I base decreases melting temperature. • The stability decreased 0>8>6>2>5>1, where numbers denotes the position replaced. • Replaced I base interacts with a cationic porphyrin, TMPyP. |
| تدمد: | 2405-5808 |
| DOI: | 10.1016/j.bbrep.2015.03.012 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::21379dc61668102cb076d432186695fb |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....21379dc61668102cb076d432186695fb |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 24055808 |
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| DOI: | 10.1016/j.bbrep.2015.03.012 |