02106nas a2200241 4500008004100000022001400041245014100055210006900196260008600265300001200351490000700363520118300370653001601553653002401569653001901593653001401612100001801626700001901644700002501663700002001688700002501708856013101733 2007 eng d a1521-654300aBile salt hydrolase, the member of Ntn-hydrolase family: differential modes of structural and functional transitions during denaturation0 aBile salt hydrolase the member of Ntnhydrolase family differenti a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcFEB a118-1250 v593 a
Conformational transitions and functional stability of the bile salt hydrolase (BSH; cholylglycine EC: 3.5.1.24) from Bifidobacterium longum (BlBSH) cloned and expressed in E. coli were studied under thermal, chemical and pH-mediated denaturation conditions using fluorescence and CD spectroscopy. Thermal and Gdn-HCl-mediated denaturation of BlBSH is a multistep process of inactivation and unfolding. The inactivation and unfolding of the enzyme was found to be irreversible. Enzyme activity seems sensitive to even minor conformational changes at the active site. Thermal denaturation as such did not result in any insoluble protein aggregates. However, on treating with 0.25-1 M Gdn-HCl the enzyme showed increasing aggregation at temperatures of 40-55 degrees C indicating more complex structural changes taking place in the presence of chemical denaturants. The enzyme secondary structure was still intact at acidic pH (pH 1-3). The perturbation in the tertiary structure at the acidic pH was detected through freshly formed solvent exposed hydrophobic patches on the enzyme. These changes could be due to the formation of an acid-induced molten globule-like state.
10aAggregation10aBile salt hydrolase10amolten-globule10aUnfolding1 aKumar, Suresh1 aSuresh, C., G.1 aBrannigan, James, A.1 aDodson, Guy, G.1 aGaikwad, Sushama, M. uhttp://library.ncl.res.in/content/bile-salt-hydrolase-member-ntn-hydrolase-family-differential-modes-structural-and-functional