小鼠基托赫索基因酶异型C的迈凯利斯样复合体
William C Gasper1, Sarah Gardner2, Adam Ross2
1Program in Biochemistry and Molecular Biology, Boston University, Boston, MA 02215, USA.
概括
果糖代谢和相关疾病中,基酶 (KHK) 是至关重要的. 这项研究呈现了小鼠KHK-C与果糖和ADP结合的高分辨率结构,揭示了对催化和潜在治疗向重要的构造变化.
科学领域:
- 生物化学和结构生物学
- 代谢疾病研究研究
背景情况:
- 在过去的40年里,与果糖相关的疾病如肥胖,心脏病和糖尿病的发病率不断上升.
- 凯托赫索酶 (KHK) 是肝脏果糖解中的一个关键酶,催化果糖酸化.
- 了解KHK的结构功能关系对于开发治疗抑制剂至关重要.
研究的目的:
- 通过高分辨率的结构分析,阐明Ketohexokinase (KHK) 的分子机制.
- 为了研究KHK在带结合和催化中的结构功能关系.
- 评估小鼠模型对于研究与 KHK 相关的疾病和治疗策略的适用性.
主要方法:
- 鼠标KHK-C (mKHK-C) 的高分辨率X射线晶体学,分辨率为1.79 Å.
- 用基质 (果糖) 和产物 (ADP) 组成的复合体中确定酶的结构.
- 结构数据与未结合的形式进行比较,以了解形状变化.
主要成果:
- 确定了mKHK-C的高分辨率晶体结构,与果糖和ADP的迈克利斯式复合物.
- 基质的结合诱导了显著的构造变化,其中β-sheet域旋转,在活性位点上形成一个盖子.
- 鼠类和人类的KHK酶表现出类似的动力参数,验证了小鼠作为KHK相关疾病研究的相关模型.
结论:
- 确定的结构为KHK-C的催化机制提供了洞察力,突出了形状变化的作用.
- 小鼠和人类KHK之间的结构和运动相似性支持在临床前研究中使用小鼠模型.
- 这种分子理解是设计向KHK抑制剂的基础,以对抗果糖相关的代谢疾病.
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