title: Beneficial effect of sugar osmolytes on the refolding of guanidine hydrochloride-denatured trehalose-6-phosphate hydrolase from Bacillus licheniformis.
abstract: The influence of three sugar osmolytes on the refolding of guanidine hydrochloride- (GdnHCl-) denatured trehalose-6-phosphate hydrolase of Bacillus licheniformis (BlTreA) was studied by circular dichroism (CD) spectra, fluorescence emission spectra, and the recovery of enzymatic activity. These experimental results clearly indicated that sorbitol, sucrose, and trehalose at a concentration of 0.75 M improved the refolding yields of GdnHCl-denatured  BlTreA, probably due to the fact that these sugars favored the formation of tertiary architectures. Far-UV CD measurements demonstrated the ability of sugar osmolytes to shift the secondary structure of GdnHCl-denatured enzyme towards near-native conformations. ANS fluorescence intensity measurements revealed a reduction of exposed hydrophobic surfaces upon the treatment of denatured enzyme with sugar osmolytes. These observations suggest that sugar osmolytes possibly play a chaperone role in the refolding of chemically denatured BlTreA.
authors: Department of Food Science and Technology, Chia-Nan University of Pharmacy and Science, Tainan City 71710, Taiwan.
authors: Jiau-Hua
authors: JH
authors: Chen
authors: Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan.
authors: Meng-Chun
authors: MC
authors: Chi
authors: Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan.
authors: Min-Guan
authors: MG
authors: Lin
authors: Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan.
authors: Long-Liu
authors: LL
authors: Lin
authors: Department of Chemistry, National Cheng Kung University, Tainan City 701, Taiwan.
authors: Tzu-Fan
authors: TF
authors: Wang
mesh_terms: D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D004186:Disaccharidases / Q000737:chemistry* / Q000378:metabolism; D004187:Disaccharides / Q000737:chemistry*; D019791:Guanidine / Q000737:chemistry*; D011489:Protein Denaturation; D058849:Protein Refolding; D013012:Sorbitol / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D004187:Disaccharides; D013012:Sorbitol; D004186:Disaccharidases; C040631:alpha, alpha-phosphotrehalase; D019791:Guanidine