PHYS 395 |
| In our studies, we measured the melting temperature of either eight or fourteen base pair- containing deoxyoligonucleotide double helices. Each class of oligonucleotides had identical composition but different sequence. From the dependence of the melting temperatures on the oligonucleotide concentration and using the van't Hoff equation, the thermodynamic parameters (ΔGo, ΔHo, ΔSo) were calculated. The results were compared with data predicted from the nearest-neighbor model for duplex stability. In an additional experiment involving a fourteen base pair oligonucleotide, the GC content was increased and the van't Hoff analysis indicated, in some cases, a lower duplex stability. This result shows that excess hydrogen bonding does not increase the stability of the duplex. Furthermore, we investigated the effect of a series of organic solvents on the stability of the double helix. The reduced stability of the duplexes with increased hydrophobicity of the solvent reinforced the stabilizing effect of the hydrophobic component of base stacking. This work has been developed as part of the Physical Chemistry On-Line (PCOL) Consortium which is a multi-university, multi-faculty effort to carry out physical chemistry projects on-line. |
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PHYS Poster Session - General Experiment
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Division of Physical Chemistry |