A Single N-Acetylgalactosamine Residue at Threonine 106 Modifies the Dynamics and Structure of Interferon alpha 2a around the Glycosylation Site

作者：Ghasriani Houman; Belcourt Pascal J F; Sauve Simon; Hodgson Derek J; Brochu Denis; Gilbert Michel; Aubin Yves^*

来源：Journal of Biological Chemistry, 2013, 288(1): 247-254.

DOI：10.1074/jbc.M112.413252

Enzymatic addition of GalNAc to isotopically labeled IFN alpha 2a produced in Escherichia coli yielded the O-linked glycoprotein GalNAc alpha-[C-13,N-15]IFN alpha 2a. The three-dimensional structure of GalNAc alpha-IFN alpha 2a has been determined in solution by NMR spectroscopy at high resolution. Proton-nitrogen heteronuclear Overhauser enhancement measurements revealed that the addition of a single monosaccharide unit at Thr-106 significantly slowed motions of the glycosylation loop on the nanosecond time scale. Subsequent addition of a Gal unit produced Gal(beta 1,3) GalNAc alpha-[C-13,N-15]IFN alpha 2a. This extension resulted in a further decrease in the dynamics of this loop. The methodology used here allowed the first such description of the structure and dynamics of an O-glycoprotein and opens the way to the study of this class of proteins.

• 出版日期2013-1-4