对β-1,3-木聚糖具有亲和力的31家族碳水化合物结合模块的首个晶体结构。

The first crystal structure of a family 31 carbohydrate-binding module with affinity to beta-1,3-xylan.

作者信息

Hashimoto Hiroshi, Tamai Youichi, Okazaki Fumiyoshi, Tamaru Yutaka, Shimizu Toshiyuki, Araki Toshiyoshi, Sato Mamoru

机构信息

International Graduate school of Arts and Sciences, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.

出版信息

FEBS Lett. 2005 Aug 15;579(20):4324-8. doi: 10.1016/j.febslet.2005.06.062.

DOI:10.1016/j.febslet.2005.06.062

PMID:16061225

Abstract

Here, we present the crystal structure of the family 31 carbohydrate-binding module (CBM) of beta-1,3-xylanase from Alcaligenes sp. strain XY-234 (AlcCBM31) determined at a resolution of 1.25A. The AlcCBM31 shows affinity with only beta-1,3-xylan. The AlcCBM31 molecule makes a beta-sandwich structure composed of eight beta-strands with a typical immunoglobulin fold and contains two intra-molecular disulfide bonds. The folding topology of AlcCBM31 differs from that of the large majority of other CBMs, in which eight beta-strands comprise a beta-sandwich structure with a typical jelly-roll fold. AlcCBM31 shows structural similarity with CBM structures of family 34 and family 9, which also adopt structures based on immunoglobulin folds.

摘要

在此，我们展示了嗜碱菌属XY-234菌株（AlcCBM31）的β-1,3-木聚糖酶31家族碳水化合物结合模块（CBM）的晶体结构，其分辨率为1.25埃。AlcCBM31仅与β-1,3-木聚糖具有亲和力。AlcCBM31分子形成了一个由八条β链组成的β折叠结构，具有典型的免疫球蛋白折叠，并且包含两个分子内二硫键。AlcCBM31的折叠拓扑结构与绝大多数其他CBM不同，在其他CBM中，八条β链构成具有典型果冻卷折叠的β折叠结构。AlcCBM31与34家族和9家族的CBM结构显示出结构相似性，这两个家族也采用基于免疫球蛋白折叠的结构。