7EHT

Levansucrase from Brenneria sp. EniD 312

7EHT の概要

• エントリーDOI: 10.2210/pdb7eht/pdb
• 分子名称: Levansucrase, SULFATE ION, GLYCEROL, ... (6 entities in total)
• 機能のキーワード: levansucrase, fructosyltransferase, levan synthesis, transferase
• 由来する生物種: Brenneria sp. EniD312
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 51801.31

構造登録者

Xu, W.,Hou, X.D.,Rao, Y.J.,Pijning, T.,Guskov, A.,Mu, W.M. (登録日: 2021-03-30, 公開日: 2022-04-20, 最終更新日: 2023-11-29)

主引用文献

Xu, W.,Ni, D.,Hou, X.,Pijning, T.,Guskov, A.,Rao, Y.,Mu, W.
Crystal Structure of Levansucrase from the Gram-Negative Bacterium Brenneria Provides Insights into Its Product Size Specificity.
J.Agric.Food Chem., 70:5095-5105, 2022

PubMed Abstract: Microbial levansucrases (LSs, EC 2.4.1.10) have been widely studied for the synthesis of β-(2,6)-fructans (levan) from sucrose. LSs synthesize levan-type fructo-oligosaccharides, high-molecular-mass levan polymer or combinations of both. Here, we report crystal structures of LS from the G-bacterium sp. EniD 312 (-LS) in its form, as well as of two mutants (A154S, H327A) targeting positions known to affect LS reaction specificity. In addition, we report a structure of -LS complexed with sucrose, the first crystal structure of a G-LS with a bound substrate. The overall structure of -LS is similar to that of G- and G-LSs, with the nucleophile (D68), transition stabilizer (D225), and a general acid/base (E309) in its active site. The H327A mutant lacks an essential interaction with glucosyl moieties of bound substrates in subsite +1, explaining the observed smaller products synthesized by this mutant. The A154S mutation affects the hydrogen-bond network around the transition stabilizing residue (D225) and the nucleophile (D68), and may affect the affinity of the enzyme for sucrose such that it becomes less effective in transfructosylation. Taken together, this study provides novel insights into the roles of structural elements and residues in the product specificity of LSs.

PubMed: 35388691
DOI: 10.1021/acs.jafc.2c01225

実験手法

X-RAY DIFFRACTION (1.45 Å)