5HBF

Crystal structure of human full-length chitotriosidase (CHIT1)

5HBF の概要

• エントリーDOI: 10.2210/pdb5hbf/pdb
• 分子名称: Chitotriosidase-1, GLYCEROL (3 entities in total)
• 機能のキーワード: chitotriosidase, chitin binding domain, cbm14, seeding, hydrolase
• 由来する生物種: Homo sapiens (Human)
• 細胞内の位置: Secreted: Q13231
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 107192.27

構造登録者

Fadel, F.,Zhao, Y.,Cousido-Siah, A.,Ruiz, F.X.,Mitschler, A.,Podjarny, A. (登録日: 2015-12-31, 公開日: 2016-05-04, 最終更新日: 2024-10-23)

主引用文献

Fadel, F.,Zhao, Y.,Cousido-Siah, A.,Ruiz, F.X.,Mitschler, A.,Podjarny, A.
X-Ray Crystal Structure of the Full Length Human Chitotriosidase (CHIT1) Reveals Features of Its Chitin Binding Domain.
Plos One, 11:e0154190-e0154190, 2016

PubMed Abstract: Chitinases are enzymes that catalyze the hydrolysis of chitin. Human chitotriosidase (CHIT1) is one of the two active human chitinases, involved in the innate immune response and highly expressed in a variety of diseases. CHIT1 is composed of a catalytic domain linked by a hinge to its chitin binding domain (ChBD). This latter domain belongs to the carbohydrate-binding module family 14 (CBM14 family) and facilitates binding to chitin. So far, the available crystal structures of the human chitinase CHIT1 and the Acidic Mammalian Chitinase (AMCase) comprise only their catalytic domain. Here, we report a crystallization strategy combining cross-seeding and micro-seeding cycles which allowed us to obtain the first crystal structure of the full length CHIT1 (CHIT1-FL) at 1.95 Å resolution. The CHIT1 chitin binding domain (ChBDCHIT1) structure shows a distorted β-sandwich 3D fold, typical of CBM14 family members. Accordingly, ChBDCHIT1 presents six conserved cysteine residues forming three disulfide bridges and several exposed aromatic residues that probably are involved in chitin binding, including the highly conserved Trp465 in a surface- exposed conformation. Furthermore, ChBDCHIT1 presents a positively charged surface which may be involved in electrostatic interactions. Our data highlight the strong structural conservation of CBM14 family members and uncover the structural similarity between the human ChBDCHIT1, tachycitin and house mite dust allergens. Overall, our new CHIT1-FL structure, determined with an adapted crystallization approach, is one of the few complete bi-modular chitinase structures available and reveals the structural features of a human CBM14 domain.

PubMed: 27111557
DOI: 10.1371/journal.pone.0154190

実験手法

X-RAY DIFFRACTION (1.95 Å)