MalS是大肠杆菌中的周等离子α-氨酶,具有与糖原的结合亲和力,具有独特的基质特异性
Phuong Lan Tran1,2,3, Minjee Yoo1, Sung-Gun Kim4
1Department of Food Science and Technology, Chungnam National University, 99 Daehak-Ro, Yuseong-Gu, Daejeon, 34134, Republic of Korea.
Applied microbiology and biotechnology
|February 14, 2025
概括
MalS是一种大肠杆菌酶,强烈地与糖原结合,增强其热稳定性,并表明它在细菌适应中的作用. 与其他氨基酶相比,这种酶表现出独特的动力特性.
科学领域:
- 酶学 是一种酶学.
- 微生物学 微生物学
- 结构生物学 结构生物学
背景情况:
- MalS是一种来自大肠杆菌K12的周等离子α酶,具有独特的多糖利用特性.
- 它在Enterobacteria中共享了一个保存的甘氨酸酸酶家族13催化域.
- MalS在高温 (65°C) 和独特的基质结合特性下表现出最佳活性.
研究的目的:
- 研究MalS在多糖利用中的生物化学特性和功能作用.
- 了解多糖结合对MalS热稳定性的影响.
- 阐明MalS的基质特异性和催化效率,特别是关于糖原的.
主要方法:
- 生物化学描述MalS酶活性和动力学.
- 分析MalS与各种葡萄糖聚合物的结合 afinity,如β-cyclodextrin和糖原.
- 使用AlphaFold2进行结构预测,以识别潜在的碳水化合物结合域.
- 动力学研究比较MalS活性在糖原和氨基素.
主要成果:
- MalS具有很高的热稳定性,通过与葡萄糖聚合物结合而显著增强.
- 这种酶对糖原和β-环氧德克斯特林具有强烈的亲和力.
- 动力学分析显示,相比于烯,Km较低,并改变了糖原的催化效率.
- 在初始阶段,MalS优先将糖原降解为马尔托糖 (G5).
结论:
- MalS具有独特的酶特性,包括在聚糖结时增强的热稳定性.
- 它与糖原的特定相互作用表明它在新环境中的细菌适应和生存中起着作用.
- 了解MalS-糖原相互作用可能会为致病性细菌的生存和感染机制提供见解.
相关概念视频
Allosteric Proteins-ATCase
5.6K
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...
5.6K
Ligand Binding and Linkage
4.7K
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...
4.7K
Oligosaccharide Assembly
2.8K
Protein glycosylation starts in the ER lumen and continues in the Golgi apparatus. Glycosyltransferases catalyze the addition of sugar molecules or glycosylation of proteins. Usually, these enzymes add sugars to the hydroxyl groups of selected serine or threonine residues to form O-linked glycans or the amino groups of asparagine residues to form N-linked glycans. Different positions on the same polypeptide chain can contain differently linked glycans.
Multiple sugar molecules that may or may...
Multiple sugar molecules that may or may...
2.8K
Protein Folding Quality Check in the RER
3.7K
ER is the primary site for the maturation and folding of soluble and transmembrane secretory proteins. The calnexin cycle is a specific chaperone system that folds and assesses the confirmation of N-glycosylated proteins before they can exit the ER lumen. The primary players of this quality check pipeline are the lectins, ER-resident chaperones, and a glucosyl transferase enzyme. In case the calnexin system in the lumen fails to salvage a misfolded protein, it is transported to the cytoplasm...
3.7K


