title: Comparative study on the effects of nystose and fructofuranosyl nystose in the glycation reaction on the antigenicity and conformation of β-lactoglobulin.
abstract: Our previous work indicated that the antigenicity of bovine β-lactoglobulin (β-LG) decreased after conjugation with fructo-oligosaccharides (FOS) which was related to its conformational changes. In attempt to unravel further changes of β-LG antigenicity, nystose (GF3) and 1(F)-β-fructofuranosyl nystose (GF4) of FOS were used to investigate the relationship between conformation and antigenicity. The antigenicity of β-LG after conjugated with GF3 and GF4 decreased from 143.4 to 29.5 and 31.6 μg/mL, respectively. The results of mass spectrometry revealed that the molecular weight of β-LG increased from 18.4 to 19.8 and 19.1 kDa after conjugation with GF3 and GF4, respectively. It was shown that the conformational changes of β-LG after conjugation with GF3 were bigger than that with GF4, including quenching of fluorescence intensity, the red-shift of fluorescence spectra, and the increase in sulfhydryl content. However, there was no significant difference in the antigenicity between β-LG-GF3 and β-LG-GF4 conjugates (P>0.05).
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Junzhen
authors.initials: J
authors.lastname: Zhong
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Tu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China. Electronic address: luoshunjing@aliyun.com.
authors.forename: Shunjing
authors.initials: S
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China. Electronic address: liuchengmei@aliyun.com.
authors.forename: Chengmei
authors.initials: C
authors.lastname: Liu
mesh_terms: D006031:Glycosylation; D007782:Lactoglobulins / Q000737:chemistry*; D013058:Mass Spectrometry; D008968:Molecular Conformation; D009844:Oligosaccharides / Q000737:chemistry*
chemical_list: D007782:Lactoglobulins; D009844:Oligosaccharides; C043600:fungitetraose
keywords: Antigenicity; Conformation; Conjugation; β-Lactoglobulin