4C60

Crystal structure of A. niger ochratoxinase

4C60 の概要

• エントリーDOI: 10.2210/pdb4c60/pdb
• 関連するPDBエントリー: 4C5Y 4C5Z 4C65
• 分子名称: OCHRATOXINASE (2 entities in total)
• 機能のキーワード: hydrolase, metal-dependent amidohydrolase, ochratoxin a hydrolysis, amidohydrolase superfamily
• 由来する生物種: ASPERGILLUS NIGER
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 373174.62

構造登録者

Dobritzsch, D.,Wang, H.,Schneider, G.,Yu, S. (登録日: 2013-09-17, 公開日: 2014-07-02, 最終更新日: 2023-12-20)

主引用文献

Dobritzsch, D.,Wang, H.,Schneider, G.,Yu, S.
Structural and Functional Characterization of Ochratoxinase, a Novel Mycotoxin Degrading Enzyme.
Biochem.J., 462:441-, 2014

PubMed Abstract: Ochratoxin, with ochratoxin A as the dominant form, is one of the five major mycotoxins most harmful to humans and animals. It is produced by Aspergillus and Penicillium species and occurs in a wide range of agricultural products. Detoxification of contaminated food is a challenging health issue. In the present paper we report the identification, characterization and crystal structure (at 2.2 Å) of a novel microbial ochratoxinase from Aspergillus niger. A putative amidase gene encoding a 480 amino acid polypeptide was cloned and homologously expressed in A. niger. The recombinant protein is N-terminally truncated, thermostable, has optimal activity at pH ~6 and 66°C, and is more efficient in ochratoxin A hydrolysis than carboxypeptidase A and Y, the two previously known enzymes capable of degrading this mycotoxin. The subunit of the homo-octameric enzyme folds into a two-domain structure characteristic of a metal dependent amidohydrolase, with a twisted TIM (triosephosphateisomerase)-barrel and a smaller β-sandwich domain. The active site contains an aspartate residue for acid-base catalysis, and a carboxylated lysine and four histidine residues for binding of a binuclear metal centre.

PubMed: 24947135
DOI: 10.1042/BJ20140382

実験手法

X-RAY DIFFRACTION (2.5 Å)