Spontaneous formation of liquid crystalline phases and phase transitions in highly concentrated plasmid DNA
| العنوان: | Spontaneous formation of liquid crystalline phases and phase transitions in highly concentrated plasmid DNA |
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| المؤلفون: | Hanczyc, Piotr, 1985, Matczyszyn, K., Pawlik, K., Olesiak, J., Leh, H., Buckle, M. |
| المصدر: | Liquid Crystals. 38(4):461-468 |
| مصطلحات موضوعية: | nucleic acids, fingerprint-like texture, supercoiled dna, cholesteric phase, shock, plasmid DNA, hyperchromic effect, supercoiling, thermal-denaturation, phase transition, DNA, circular dichroism, escherichia-coli, growth temperature, microscopy, bacteria, liquid crystal, linking, dimensions, isolation techniques |
| الوصف: | The liquid crystalline (LC) properties of two supercoiled plasmid DNA samples, pBSK (2958 bp) and pGEM (3000 bp), have been studied using polarised light microscopy (PLM), circular dichroism (CD) and UV-Vis spectroscopy. The influence of methods of isolation on plasmid LC behaviour is described, and using PLM we have demonstrated the spontaneous formation of cholesteric fingerprint-like textures. Preliminary studies of LC phase transitions in pGEM show the irreversibility of LC phase formation, as a consequence of changes in the tertiary structure of supercoiled plasmids. Using UV-Vis spectroscopy a hyperchromic effect was observed with increasing temperature. The CD spectra clearly showed structural changes, and probably mismatching of DNA bases, during cooling. Finally, we have observed an irreversible phase transition in plasmid DNA which is very different from that previously reported in linear DNA. |
| وصف الملف: | electronic |
| URL الوصول: | https://research.chalmers.se/publication/140604 http://publications.lib.chalmers.se/records/fulltext/local_140604.pdf |
| قاعدة البيانات: | SwePub |
PDF full text from Publisher | تدمد: | 13665855 02678292 |
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| DOI: | 10.1080/02678292.2011.552740 |