鈥楴aked鈥?and Hydrated Conformers of the Conserved Core Pentasaccharide of N-linked Glycoproteins and Its Building Blocks

详细信息    查看全文

• 作者：Conor S. Barry ; Emilio J. Cocinero ; Pierre 脟ar莽abal ; David P. Gamblin ; E. Cristina Stanca-Kaposta ; Sarah M. Remmert ; Mar铆a C. Fern谩ndez-Alonso ; Svemir Rudi膰 ; John P. Simons ; Benjamin G. Davis
• 刊名：Journal of the American Chemical Society
• 出版年：2013
• 出版时间：November 13, 2013
• 年：2013
• 卷：135
• 期：45
• 页码：16895-16903
• 全文大小：549K
• 年卷期：v.135,no.45(November 13, 2013)
• ISSN：1520-5126

文摘

N-glycosylation of eukaryotic proteins is widespread and vital to survival. The pentasaccharide unit 鈭扢an₃GlcNAc₂鈥?lies at the protein-junction core of all oligosaccharides attached to asparagine side chains during this process. Although its absolute conservation implies an indispensable role, associated perhaps with its structure, its unbiased conformation and the potential modulating role of solvation are unknown; both have now been explored through a combination of synthesis, laser spectroscopy, and computation. The proximal 鈭扜lcNAc-GlcNAc鈥?unit acts as a rigid rod, while the central, and unusual, 鈭扢an-尾-1,4-GlcNAc鈥?linkage is more flexible and is modulated by the distal Man-伪-1,3鈥?and Man-伪-1,6鈥?branching units. Solvation stiffens the 鈥榬od鈥?but leaves the distal residues flexible, through a 尾-Man pivot, ensuring anchored projection from the protein shell while allowing flexible interaction of the distal portion of N-glycosylation with bulk water and biomolecular assemblies.