Structural based fruit softening mechanism; the model of tomato fruit softening during maturation

基于结构的水果软化机制；

• 批准号: 23580054
• 负责人: ISHIMARU Megumi
• 金额: $ 2.83万
• 依托单位: Kinki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011 至 2013
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23580054/
• 关键词: 果実軟化; 細胞壁; トマト果実; β-ガラクトシダーゼ; 細胞壁分解酵素; 基質特異性; 構造解析

In tomato fruit, beta-galactosidase 4 (TBG4) is an enzyme responsible for fruit softening through the degradation of beta-(1,4)-galactan in the pericarp cell wall. To gain structural insight into the substrate specificity, we determined the crystal structures of TBG4 and its complex with beta-D-galactose. TBG4 was composed of a catalytic TIM barrel domain followed by three beta-sandwich domains. This structure is similar to other beta-galactosidase belong to GH35 families.In addition, we determined the enzymatic properties and substrate specificities of TBG1. TBG4 has substrate recognition to beta-(1,4)-linkage, however, TBG1 has beta-(1,3) and beta-(1,6)-likage substrate.In these results, TBG's act on the tomato cell wall during fruits development and maturation, and seberal stage of tomato fruits cell walls construct/reconstruct to some components sugar as a substrate against TBG's.

在番茄果实中，β-半乳糖苷酶4（TBG 4）是一种负责通过降解果皮细胞壁中的β-（1，4）-半乳聚糖来软化果实的酶。为了获得对底物特异性的结构洞察，我们确定了TBG 4及其与β-D-半乳糖的复合物的晶体结构。TBG 4由催化TIM桶结构域和随后的三个β-夹心结构域组成。此外，我们还对TBG 1的酶学性质和底物特异性进行了研究。TBG 4对β-（1，4）-连接有底物识别作用，而TBG 1对β-（1，3）和β-（1，6）-连接有底物识别作用，说明TBG在番茄果实发育成熟过程中作用于细胞壁，成熟期番茄果实细胞壁以糖为底物进行构建/重构。

项目成果

トマトβ-ガラクトシダーゼ4の結晶構造解析

番茄β-半乳糖苷酶4的晶体结构分析

• 发表时间: 2013
• 作者: Fujii;H.;T. Shimada;K. Nonaka;M. Kita;T. Kuniga;T. Endo;Y. Ikoma;M. Omura;石丸恵,枝真広,多田俊治
• 通讯作者: 石丸恵,枝真広,多田俊治

Crystal structures of a glycoside hydrolase family 35 β-galactosidase from

糖苷水解酶家族 35 β-半乳糖苷酶的晶体结构

• 发表时间: 2013
• 作者: M. Tsuro;A. Sakuma and M. Mino;高田修治;Megumi Ishimaru
• 通讯作者: Megumi Ishimaru

トマトβ-ガラクトシダーゼ(TBG)4の結晶化

番茄 β-半乳糖苷酶 (TBG)4 的结晶

• 发表时间: 2011
• 作者: 小島仁志;大澤啓志;勝野武彦;カーンM. M. R.・ハスヌンナハルM.・岩吉真輝・一色司郎;石丸恵,枝真広,多田俊治
• 通讯作者: 石丸恵,枝真広,多田俊治

Crystal structures of a glycoside hydrolase family 35β-galactosidase from Solanum lycopersicum

番茄糖苷水解酶家族 35β-半乳糖苷酶的晶体结构

• 发表时间: 2013
• 作者: Megumi Ishimaru;Masahiro Eda;Toshiji Tada
• 通讯作者: Toshiji Tada

Crystallization and preliminary X-ray diffraction analysis of tomatoβ-galactosidase 4

番茄β-半乳糖苷酶4的结晶和初步X射线衍射分析

• 发表时间: 2011
• 作者: EGUMI ISHIMARU;MASAHIRO EDA;HIDEMI IZUMI
• 通讯作者: HIDEMI IZUMI