报告题目：Quantitatively Studying the Effects of Cellulase Glycosylation

　　报 告 人：Assistant Prof. Zhongping TAN（谭忠平）

　　工作单位：University of Colorado

　　报告时间：2015年6月16日（星期二）10:00-11:00

　　报告地点：行政楼205报告厅

　　报告人简介：

　　Education Experiences:

　　2000-2005, Master and doctor degree, Chemicobiology, Columbia University

　　Supervisor: Prof. Virginia W. Cornish

　　1992-2000, bachelor and master degree, Organic Chemistry, Peking University

　　Supervisor: Prof. Jianbo Wang

　　

　　Research Experiences:

　　2011-now, Assistant Professor, Chemical Glycobiology, University of Colorado

　　2005-2011, Postdoctoral Fellow, Bioorganic Chemistry, Memorial Sloan-Kettering Cancer Center

　　Supervisor: Prof. Samuel J. Danishefsky

　　

　　Tan’s Research Group: http://chem.colorado.edu/tangroup/

　　

　　Research Focuses:

　　Tan’s lab studies the effects of glycosylation on protein structure and activity. Protein glycosylation is an important post-translational modification. It enhances the functional diversity of proteins and alters their conformation, stability and biological activity. However, because of the complexity of glycoproteins and glycan structures, establishing connections between glycan structures and their functions is difficult. Recently, we demonstrate that chemical glycobiology can be employed as a useful tool to determine the effects of protein glycosylation and the molecular mechanisms of these effects. The more precise understanding of protein glycosylation would aid in the development of enzymes and protein-based therapeutics with improved properties.

　　

　　Selected Publications:

　　(1) “New methods for chemical protein synthesis”, X. Guan, P.K. Chaffey, C. Zeng, Z. Tan,* Top Curr Chem, 2015, 363, 155-192.

　　(2) “Specificity of O-glycosylation in enhancing the stability and cellulose binding affinity of Family 1 carbohydrate-binding modules”, L. Chen, M.R. Drake, M.G. Resch, E.R. Greene, M.E. Himmel, P.K. Chaffey, G.T. Beckham,* Z. Tan*, Proc Natl Acad Sci USA, 2014, 111, 7612-7617.

　　(3) “Glycosylated linkers in multi-modular lignocellulose degrading enzymes dynamically bind to cellulose”, C.M. Payne, M.G. Resch, L. Chen, M.F. Crowley, M.E. Himmel, L.E. Taylor, M. Sandgren, J. St?hlberg, I. Stals,* Z. Tan,* G.T. Beckham,* Proc Natl Acad Sci USA, 2013, 110, 14646-14651.

　　(4) “Total synthesis of human galanin-like peptide through an aspartic acid ligation”, X. Guan, M.R. Drake, Z. Tan*, Org Lett, 2013, 15, 6128-6131.

　　(5) “A convenient and efficient synthetic approach to mono-, di-, and tri-O-mannosylated Fmoc amino acids”, L. Chen, Z. Tan*, Tetrahedron Lett, 2013, 54, 2190-2193.

　　报告摘要：

　　糖基化是纤维素酶最重要的修饰之一。基于以前的研究，人们认为糖基化能极大地提高纤维素酶的功能多样性。这可能主要是通过改变酶的构象、溶解性、稳定性、底物结合力，以及底物专一性得以实现的。然而，由于糖基化与生俱来的复杂性，关于糖基化作用的定量知识极度匮乏。最近，我们证明了化学合成可以作为一个有效的工具来定量分析糖基化的作用和定义这些作用的分子决定因素。我们的发现突出了氨基酸环境和糖的大小、类型，以及链接的共同重要性。根据我们的结论，在今后，可能可以通过改变糖结构和糖基化位点附近的氨基酸序列来同时提高纤维素酶的多种性能。