相关实验视频

Updated: Sep 14, 2025

Glutamine Flux Imaging Using Genetically Encoded Sensors

Glutamine Flux Imaging Using Genetically Encoded Sensors

Published on: July 31, 2014

通过的可用性来调节谷氨胺合成酶腺化,使单步净化能够在不同的翻译后状态中进行

Larissa Fonseca Tomazini¹, Eduardo Sabatine Lopes¹, Bárbara Barizão Nogueira¹

¹Department of Biochemistry, Maringa State University, Maringa, Brazil.

Protein expression and purification

|July 18, 2025

概括

研究人员开发了一种简单的方法来净化细菌谷氨酸合成酶 (GS) 在不同的基化状态. 这种技术通过改变细胞生长过程中的可用性,有助于研究GS调节和功能.

科学领域:

生物化学生物化学
分子生物学分子生物学
微生物的新陈代谢

背景情况:

谷氨酸合成酶 (GS) 对于细菌氨同化和氨基酸平衡至关重要.
细菌的GS活性由可逆腺化调节,由GlnE酶控制,以响应水平.
腺基化改变了GS的催化活性,辅因子偏好和反抑制敏感性,使得纯化的酶状态对研究有价值.

研究的目的:

建立一种简单的方法,以在不同的腺化状态下净化细菌GS.
为了研究在表达过程中的可用性如何影响GS腺化状态.
描述不同GS异型体的调节性质和基质结合.

主要方法:

在M9介质中,来自Herbaspirillum seropedicae和Azospirillum brasilense的GS酶的异质表达.
用不同的源 (氨或谷氨) 进行培养,以诱导不同的腺化状态.
使用Ni2+-亲和力染色法对GS进行单步净化.

主要成果:

通过简单地在表达过程中改变源,GS酶在基化和未修改状态中成功净化.
电泳运动移动性转移证实了纯化GS异型体的不同腺化状态.
独特的GS异型对双价 (Mg2+,Mn2+) 和氨基酸的反抑制表现出独特的反应;未经修改的GS需要ATP来结合谷氨酸.

结论:

在细胞生长过程中调节的可用性提供了一种简单而有效的策略,以在各种腺化状态下获得细菌GS.
这种单步净化方法有助于详细描述GS调节性质和酶机制.
这些发现为未来对这种必不可少的代谢酶的研究提供了宝贵的工具.

关键词:

亚基化是亚基化的一种方法.谷氨胺合成酶的使用的新陈代谢的新陈代谢蛋白质净化蛋白质的净化蛋白质 - 配体相互作用

更多相关视频

Evaluation of Amino Acid Consumption in Cultured Bone Cells and Isolated Bone Shafts

Evaluation of Amino Acid Consumption in Cultured Bone Cells and Isolated Bone Shafts

Published on: April 13, 2022

Assessment of Glutamine as a Fuel Source for Alveolar Macrophages Exposed to Chronic Ethanol Using an Extracellular Flux Bioanalyzer

Assessment of Glutamine as a Fuel Source for Alveolar Macrophages Exposed to Chronic Ethanol Using an Extracellular Flux Bioanalyzer

Published on: November 15, 2024

相关概念视频

Inorganic Nitrogen Assimilation

Inorganic Nitrogen Assimilation

Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme...

Stringent Response in E. coli

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...

Biosynthesis of Nucleic Acids

Biosynthesis of Nucleic Acids

Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...

Amino Acid Biosynthetic Pathways

Amino Acid Biosynthetic Pathways

Amino acid biosynthesis is essential for cell growth, protein synthesis, and metabolic regulation. Cells generate essential and non-essential amino acids from metabolic intermediates to sustain vital biological functions. These intermediates originate from key metabolic pathways: glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway. Important precursors include α-ketoglutarate, pyruvate, oxaloacetate, phosphoenolpyruvate, and erythrose-4-phosphate, which...

Overview of Metabolism

Overview of Metabolism

Living cells constantly carry out various chemical reactions which are necessary for their proper functioning. These reactions are interlinked to one another via multiple pathways. The collection of these chemical reactions is known as metabolism.
Plant Metabolism
Sunlight, the primary source of energy in plants, is first absorbed by the chlorophyll pigments present in their leaves. Plants then use this energy to carry out photosynthesis, where water is oxidized into oxygen and carbon dioxide...

Regulation of Metabolism

Regulation of Metabolism

Cellular needs and conditions vary from cell to cell and change within individual cells over time. For example, the required enzymes and energetic demands of stomach cells are different from those of fat storage cells, skin cells, blood cells, and nerve cells. Furthermore, a digestive cell works much harder to process and break down nutrients during the time that closely follows a meal compared with many hours after a meal. As these cellular demands and conditions vary, so do the amounts and...