Calorimetric and dielectrpspectroscopic studies of energy-transfer mechanism of within a protein molecule

蛋白质分子内能量转移机制的量热和介电光谱研究

• 批准号: 13680744
• 负责人: KODAMA Takao
• 金额: $ 2.24万
• 依托单位: Kyushu Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680744/
• 关键词: Calorimetry; Dielectric spectroscony; Glucosyltransferase; Domain-domain interaction; Enthalpy; Entropy; Hydroahobic interaction; ΔH; ΔS compensation

The I-type of glucosyltransferase of Streptococcus sobrinus was used to study the of energy-transfer mechanism of within a protein molecule. Protein samples of whole GTF molecule(GTF), its catalytic domain (GS) and glucanbinding domain (DXB) were subjected to differential scanning calorimetry and dielectric and CD spectroscopies. DSC results indicated the enthalpy change of thermal denaturation of GTF{ΔH(GTF)} <ΔH(GS)+ ΔH(DXB). In addition, the T_m (mid-temperature of thermal denaturatin) of GS fused with DXB (within GTF) was lower than that of un-fused GS, whereas T_m of DXB fused with GS (within GTF) was higher than that of un-fused DXB. These results indicate that fusion of GS and DXB may destabilize the former and stabilize the latter. However, CD-spectroscopy indicated that the fusion did not affect the secondary and higher-order structures of either domains. In accordance with this result, dielectroscopy did not show any significant hydration change accompanying the domain fusion.

利用远缘链球菌I型葡萄糖基转移酶研究蛋白质分子内的能量传递机制。对整个GTF分子（GTF）、其催化结构域（GS）和葡聚糖结合结构域（DXB）的蛋白样品进行差示扫描量热法、介电谱和CD谱。DSC结果表明，GTF的热变性焓变{ΔH（GTF）} <ΔH（GS）+ ΔH（DXB）。此外，与DXB融合的GS（GTF内）的T_m（热变性中间温度）低于未融合的GS，而与DXB融合的GS（GTF内）的T_m高于未融合的DXB。这些结果表明，GS和DXB的融合可以使前者不稳定而使后者稳定。然而，CD光谱表明融合并不影响两个结构域的二级和高级结构。根据这个结果，介电没有显示出任何显著的水合变化伴随着域融合。

项目成果

亀井 敬, 児玉 孝雄, 稲積 広平, 鈴木 誠: "グルコシルトランスフェラーゼにおけるドメイン間相互作用の水和量測定による解析"生物物理. 42・Supplement2. S19 (2002)

Takashi Kamei、Takao Kodama、Kohei Inazumi、Makoto Suzuki：“通过测量水合作用分析葡萄糖基转移酶中的域间相互作用”生物物理学 42·补充 S19。

NaziaUmmeSalma, Kabir Syed Rashel, 降旗佳男, 児玉孝雄, 鈴木誠: "Dielectric property of Alkali-Halide salts with hydration shells in water"生物物理. 43・S1. S26 (2003)

NaziaUmmeSalma、Kabir Syed Rashel、Yoshio Furuhata、Takao Kodama、Makoto Suzuki：“水中具有水合壳的碱卤化物盐的介电性能” 43・S1。

小松 英幸, 児玉 孝雄: "口腔連鎖球菌由来グルコシルトランスフェラーゼの自発的フォールディング"生物物理. 42・Supplement2. S189 (2002)

Hideyuki Komatsu，Takao Kodama：“口腔链球菌的葡萄糖基转移酶的自发折叠”生物物理学42·补充2。