The binding of small volatile molecules by bovine [beta]-lactoglobulin : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry at Massey University

Hsu, Yu-Ting

The binding of small volatile molecules by bovine [beta]-lactoglobulin : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry at Massey University

dc.contributor.author	Hsu, Yu-Ting
dc.date.accessioned	2009-04-28T23:29:23Z
dc.date.available	NO_RESTRICTION	en_US
dc.date.available	2009-04-28T23:29:23Z
dc.date.issued	2008
dc.description.abstract	Bovine ß-lactoglobulin (ß-Lg) has been studied extensively but there is no clear identification of its biological function. Hydrophobic molecules have been observed binding into the hydrophobic calyx of ß-Lg. By comparison with other members of lipocalin family, it is probable that ß-Lg plays a role of transport of ligands, as ligands also bind into the central cavity of lipocalins. The structurally similar MUP is a pheromone-binding protein; therefore, it is possible that ß-Lg may also fulfil a similar role. This study has begun to test this hypothesis by investigating the interactions between bovine ß-Lg and several small volatile molecules (2-sec-4,5-dihydrothiazole, 3-methyl-2-butenal, 3-methyl-2-buten-1-ol and phenylacetic acid). The interactions between the volatile molecules and ß-Lg were studied by both two-dimensional NMR spectroscopy and X-ray crystallographic methods. TOCSY spectra were recorded for ß-Lg and the complex between ß-Lg and the ligands. The observed chemical shifts in the HN-Ha region are sensitive to the proximity of ligands, and hence chemical shift changes on ligand binding provide information on possible binding sites. It appears that several amino acids with hydrophobic sidechains are affected by interaction with volatile molecules at pH 2.0. The X-ray crystallographic study at pH 8.5 showed that the potential ligand, 2-sec-4,5-dihydrothiazole, may have decomposed into a linear 2-methyl-butanol. The refined structure (R=0.281, Rfree=0.354 for reflections to 2.6 Å resolution) reveals that the potential ligand may bind to the central cavity in a manner similar to the binding of 12-bromodecanoic acid to ß-Lg.	en_US
dc.identifier.uri	http://hdl.handle.net/10179/771
dc.language.iso	en	en_US
dc.publisher	Massey University	en_US
dc.rights	The Author	en_US
dc.subject	Bovine [beta]-lactoglobulin	en_US
dc.subject	Molecular biology	en_US
dc.subject.other	Fields of Research::250000 Chemical Sciences::250300 Organic Chemistry	en_US
dc.title	The binding of small volatile molecules by bovine [beta]-lactoglobulin : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry at Massey University	en_US
dc.type	Thesis	en_US
massey.contributor.author	Hsu, Yu-Ting
thesis.degree.discipline	Chemistry	en_US
thesis.degree.level	Masters	en_US
thesis.degree.name	Master of Science (M.Sc.)	en_US