II型抗冻蛋白的溶液结构揭示了凝集素家族的一个新成员。

The solution structure of type II antifreeze protein reveals a new member of the lectin family.

作者信息

Gronwald W, Loewen M C, Lix B, Daugulis A J, Sönnichsen F D, Davies P L, Sykes B D

机构信息

Protein Engineering Network of Centres of Excellence, University of Alberta, Edmonton, Alberta T6G 2S2, Canada.

出版信息

Biochemistry. 1998 Apr 7;37(14):4712-21. doi: 10.1021/bi972788c.

DOI:10.1021/bi972788c

PMID:9537986

Abstract

A recombinant form of the sea raven type II antifreeze protein (SRAFP) has been produced using the Pichia pastoris expression system. The antifreeze activity of recombinant SRAFP is indistinguishable from that of the wild-type protein. The global fold of SRAFP has been determined by two-dimensional 1H homonuclear and three-dimensional 1H-¿15N¿ heteronuclear NMR spectroscopy using 785 NOE distance restraints and 47 angular restraints. The molecule folds into one globular domain that consists of two helices and nine beta-strands in two beta-sheets. The structure confirms the proposed existence of five disulfide bonds. The global fold of SRAFP is homologous to C-type lectins and pancreatic stone proteins, even though the sequence identity is only approximately 20%.

摘要

利用毕赤酵母表达系统制备了重组形式的海鸦II型抗冻蛋白（SRAFP）。重组SRAFP的抗冻活性与野生型蛋白的抗冻活性无明显差异。通过二维1H同核和三维1H-15N异核核磁共振光谱，利用785个NOE距离约束和47个角度约束确定了SRAFP的整体折叠结构。该分子折叠成一个球状结构域，由两条螺旋和两个β-折叠中的九条β-链组成。该结构证实了所提出的五个二硫键的存在。尽管序列同一性仅约为20%，但SRAFP的整体折叠与C型凝集素和胰腺结石蛋白同源。