The Effects of Trimethylamine-N-Oxide and Guanidinium Chloride on Aqueous Hydrophobic Contact-Pair Interactions
| dc.contributor.author | Macdonald, Ryan | |
| dc.contributor.examiningcommittee | O'Neil, Joe (Chemistry) Stout, Jake (Biological Science) | en_US |
| dc.contributor.supervisor | Khajehpour, Mazdak (Chemistry) | en_US |
| dc.date.accessioned | 2015-01-07T21:04:23Z | |
| dc.date.available | 2015-01-07T21:04:23Z | |
| dc.date.issued | 2013 | en_US |
| dc.date.issued | 2015 | en_US |
| dc.degree.discipline | Chemistry | en_US |
| dc.degree.level | Master of Science (M.Sc.) | en_US |
| dc.description.abstract | Trimethylamine-N-oxide (TMAO) and guanidinium chloride (GdmCl) are both highly studied molecules in the field of protein folding/unfolding. Thermodynamic studies have shown that TMAO, an organic osmolyte, is a strong stabilizer of the protein folded state, while GdmCl is known to be one of the most effective protein denaturants. Although TMAO and GdmCl are well studied the mechanism by which they stabilize and denature proteins, respectively, is not well understood. In fact there are few studies looking at their effects on hydrophobic interactions. In this work we determine the effect of TMAO and GdmCl on hydrophobic interactions, by looking at the model system of phenyl and alkyl hydrophobic contact pairs. Contact pair formation is monitored through the use of fluorescence spectroscopy, i.e., measuring the intrinsic phenol fluorescence being quenched by carboxylate ions. Hydrophobic interactions are isolated from other interactions through a developed methodology. The results show that TMAO addition to the aqueous solvent destabilizes hydrophobic contact-pairs formed between phenol and carboxylate ions. The TMAO acts as a “denaturant” for hydrophobic interactions. For GdmCl the data shows that for small alkyl groups, acetate and propionate, hydrophobic contact-pairs are slightly stabilized or are not affected, respectively. For the larger alkyl groups GdmCl disrupts contact pair formation and destabilizes them. GdmCl’s effect on hydrophobic interactions shows a size dependence on carboxylate ion size, i.e., as carboxylate ion tail length increases the contact pair formed with phenol is destabilized to a greater degree. | en_US |
| dc.description.note | February 2015 | en_US |
| dc.identifier.citation | R.D. Macdonald, M. Khajehpour, Effects of the osmolyte TMAO (Trimethylamine-N-oxide) on aqueous hydrophobic contact-pair interactions, Biophysical Chemistry, 184 (2013) 101-107. | en_US |
| dc.identifier.citation | R.D. Macdonald, M. Khajehpour, Effects of the protein denaturant guanidinium chloride on aqueous hydrophobic contact-pair interactions, Biophysical Chemistry, 196 (2015) 25-32. | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/30162 | |
| dc.language.iso | eng | en_US |
| dc.publisher | Elsevier - Biophysical Chemistry | en_US |
| dc.publisher | Elsevier - Biophysical Chemistry | en_US |
| dc.rights | open access | en_US |
| dc.subject | Hydrophobic | en_US |
| dc.subject | Interactions | en_US |
| dc.title | The Effects of Trimethylamine-N-Oxide and Guanidinium Chloride on Aqueous Hydrophobic Contact-Pair Interactions | en_US |
| dc.type | master thesis | en_US |