6JR7

Flavobacterium johnsoniae GH31 dextranase, FjDex31A, complexed with glucose

6JR7 の概要

• エントリーDOI: 10.2210/pdb6jr7/pdb
• 関連するPDBエントリー: 6JR6 6JR8
• 分子名称: Candidate alpha-glycosidase Glycoside hydrolase family 31, alpha-D-glucopyranose-(1-6)-alpha-D-glucopyranose, ACETATE ION, ... (5 entities in total)
• 機能のキーワード: dextranase, flavobacterium johnsoniae, dextran, isomaltose, gh31, hydrolase
• 由来する生物種: Flavobacterium johnsoniae (strain ATCC 17061 / DSM 2064 / UW101) (Cytophaga johnsonae)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 387339.71

構造登録者

Tonozuka, T. (登録日: 2019-04-02, 公開日: 2019-04-24, 最終更新日: 2024-10-16)

主引用文献

Tsutsumi, K.,Gozu, Y.,Nishikawa, A.,Tonozuka, T.
Structural insights into polysaccharide recognition by Flavobacterium johnsoniae dextranase, a member of glycoside hydrolase family 31.
Febs J., 287:1195-1207, 2020

PubMed Abstract: Glycoside hydrolase family (GH) 31 contains a large variety of enzymes, but the major members are enzymes that act on relatively small oligosaccharides such as α-glucosidase. Here, we determined the crystal structure of Flavobacterium johnsoniae dextranase (FjDex31A), an enzyme from F. johnsoniae that hydrolyzes a polysaccharide, dextran. FjDex31A is composed of four domains: an N-terminal domain, a catalytic domain, a proximal C-terminal domain, and a distal C-terminal domain, as observed in typical GH31 enzymes. However, the architecture of active site residues in FjDex31A, other than subsite -1, is markedly different from that of other GH31 enzymes. The FjDex31A structure in complex with isomaltotriose shows that Gly273 and Tyr524, both of which interact with an α-glucose residue at subsite -2, as well as Trp376 and Leu308-cisGln309, are especially unique to FjDex31A. Site-directed mutagenesis of Gly273 and Tyr524 resulted in a decrease in the hydrolysis of polysaccharides dextran and pullulan, as well as that of the disaccharide isomaltose. These results suggest that, regardless of the length of sugar chains of the substrates, binding of FjDex31A to the substrates at subsite -2 is likely to be important for its activity. DATABASE: Structural data are available in the Protein Data Bank under the accession numbers 6JR6, 6JR7, and 6JR8.

PubMed: 31552702
DOI: 10.1111/febs.15074

実験手法

X-RAY DIFFRACTION (1.75 Å)