7BWC

Bombyx mori GH32 beta-fructofuranosidase BmSUC1 mutant D63A in complex with sucrose

7BWC の概要

• エントリーDOI: 10.2210/pdb7bwc/pdb
• 関連するBIRD辞書のPRD_ID: PRD_900003
• 分子名称: Beta-fructofuranosidase, beta-D-fructofuranose-(2-1)-alpha-D-glucopyranose (3 entities in total)
• 機能のキーワード: glycoside hydrolase, sucrose, beta-propeller, horizontal gene transfer, hydrolase
• 由来する生物種: Bombyx mori (Silk moth)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 56365.56

構造登録者

Miyazaki, T.,Oba, N. (登録日: 2020-04-14, 公開日: 2020-11-04, 最終更新日: 2023-11-29)

主引用文献

Miyazaki, T.,Oba, N.,Park, E.Y.
Structural insight into the substrate specificity of Bombyx mori beta-fructofuranosidase belonging to the glycoside hydrolase family 32.
Insect Biochem.Mol.Biol., 127:103494-103494, 2020

PubMed Abstract: Sucrose-hydrolyzing enzymes are largely divided into β-fructofuranosidase and sucrose α-glucosidase. The domestic silkworm Bombyx mori possesses both enzymes, BmSUC1 and BmSUH, belonging to the glycoside hydrolase family 32 (GH32) and GH13, respectively. BmSUC1 was presumed to be acquired by horizontal gene transfer from bacteria based on phylogenetic analysis and related to tolerance to sugar-mimic alkaloids contained in mulberry latex. Here we investigated the substrate specificity of recombinant BmSUC1 that can hydrolyze not only sucrose but also fructooligosaccharides and fructans, and revealed that the enzyme was competitively inhibited by 1,4-dideoxy-1,4-imino-D-arabinitol, one of the alkaloids. Moreover, the crystal structures of BmSUC1 in apo form and complex with sucrose were determined, and the active site pocket was shallow and suitable for shorter substrates but was related to more relaxed substrate specificity than the strict sucrose α-glucosidase BmSUH. Considering together with the distribution of BmSUC1-orthologous genes in many lepidopterans, our results suggest that BmSUC1 contributes to the digestion of fructooligosaccharides and fructans derived from feed plants.

PubMed: 33132139
DOI: 10.1016/j.ibmb.2020.103494

実験手法

X-RAY DIFFRACTION (1.95 Å)