对Arabidopsis thaliana谷氨酸脱酶异型2的结构和功能研究表明了酶动态,并确定了它的结合位
Marta Grzechowiak1, Joanna Sliwiak2, Mariusz Jaskolski3
1Department of Structural Biology of Eukaryotes, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, 61-704, Poland.
Plant physiology and biochemistry : PPB
|July 21, 2023
概括
酸盐脱酶 (GDH) 在Arabidopsis thaliana,特别是AtGDH2,在一个非催化部位结合. 尽管如此,AtGDH2是最常见的异型,这表明的结构作用.
科学领域:
- 植物生物化学 植物生物化学
- 酶学 是一种酶学.
- 分子生物学分子生物学
背景情况:
- 谷氨酸脱酶 (GDH) 是植物和碳代谢中的一个关键酶,催化了2-氧谷氨酸和谷氨酸的相互转化.
- 阿拉比多普西斯塔利亚纳具有三种GDH异型:AtGDH1,AtGDH2和AtGDH3,AtGDH2是本研究的重点.
- 之前的研究表明,GDH同类在联合酶结合域内具有结合的EF手动图案.
研究的目的:
- 为了研究阿拉比多普西斯塔利亚纳GDH2 (AtGDH2) 的结合特性.
- 描述结合对AtGDH2活动的结构和功能影响.
- 为了比较AtGDH1和AtGDH2的动力性质,并分析它们的基因表达特征.
主要方法:
- 频谱学方法 频谱学方法
- 异热量定位热量计 异热量定位热量计
- 基因表达特征分析
主要成果:
- 在GDH2结合,但不是在预测的EF手动图案;结合部位距离活性部位超过20 Å,表明结构性作用.
- 比较动力学分析显示,AtGDH1和AtGDH2的行为大致相似,而的影响很小.
- 空间和时间基因表达分析表明AtGDH2是Arabidopsis thaliana中最常见的GDH异型.
结论:
- 在AtGDH2中的结合部位在结构上重要,而不是具有催化意义.
- AtGDH1和AtGDH2具有相似的酶特性,的调节最小.
- 在GDH2被确定为占主导地位的GDH异型,尽管其结合位点的非催化作用.
相关概念视频
00:49Ligand Binding and Linkage
4.8K
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence...
4.8K
01:19Allosteric Proteins-ATCase
5.8K
Binding sites linkages can regulate a protein's function. For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
5.8K
01:16Calmodulin-dependent Signaling
5.2K
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
5.2K