Structural and biochemical characterization of a multidomain alginate lyase reveals a novel role of CBM32 in CAZymes

被引：49

作者：

Lyu, Qianqian ^{[1
,2
]}

Zhang, Keke ^{[1
]}

Zhu, Qiaoyun ^{[1
]}

Li, Zhijian ^{[1
]}

Liu, Yujie ^{[1
]}

Fitzek, Elisabeth ^{[3
]}

Yohe, Tanner ^{[3
]}

Zhao, Liming ^{[4
]}

Li, Weihua ^{[5
]}

Liu, Tao ^{[1
]}

Yin, Yanbin ^{[3
]}

Liu, Weizhi ^{[1
,2
]}

机构：

[1] Ocean Univ China, Coll Marine Life Sci, MOE Key Lab Marine Genet & Breeding, Qingdao 266003, Peoples R China

[2] Qingdao Natl Lab Marine Sci & Technol, Lab Marine Biol & Biotechnol, Qingdao 266235, Peoples R China

[3] Northern Illinois Univ, Dept Biol Sci, De Kalb, IL 60115 USA

[4] R&D Ctr Separat & Extract Technol Fermentat Ind, Sch Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

[5] East China Univ Sci & Technol, Shanghai Key Lab New Drug Design, Sch Pharm, Shanghai 200237, Peoples R China

来源：

BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS | 2018年 / 1862卷 / 09期

基金：

美国国家卫生研究院; 中国国家自然科学基金; 美国国家科学基金会; 中国博士后科学基金;

关键词：

CBM32; Alginate lyase; Alpha helix linker; X-ray crystallography; Molecular docking; BINDING; IDENTIFICATION; METABOLISM; MODULES; PROTEIN;

D O I：

10.1016/j.bbagen.2018.05.024

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Noncatalytic carbohydrate binding modules (CBMs) have been demonstrated to play various roles with cognate catalytic domains. However, for polysaccharide lyases (PLs), the roles of CBMs remain mostly unknown. AIyB is a multidomain alginate lyase that contains CBM32 and a PL7 catalytic domain. The AIyB structure determined herein reveals a noncanonical alpha helix linker between CBM32 and the catalytic domain. More interestingly, CBM32 and the linker does not significantly enhance the catalytic activity but rather specifies that trisaccharides are predominant in the degradation products. Detailed mutagenesis, biochemical and cocrystallization analyses show "weak but important" CBM32 interactions with alginate oligosaccharides. In combination with molecular modeling, we propose that the CBM32 domain serves as a "pivot point" during the trisaccharide release process. Collectively, this work demonstrates a novel role of CBMs in the activity of the appended PL domain and provides a new avenue for the well-defined generation of alginate oligosaccharides by taking advantage of associated CBMs.

引用

页码：1862 / 1869

页数：8

共 30 条

[21] Structural basis for controlling the enzymatic properties of polymannuronate preferred alginate lyase FlAlyA from the PL-7 family [J].