定义Enterococcus faecalis脂肪酸激酶系统的外源性脂肪酸利用方法
Huijuan Dong1, Qi Zou1, John E Cronan1,2
1Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Molecular microbiology
|August 2, 2025
概括
固态细菌利用独特的酸来合成脂. 这项研究研究了FakB蛋白质的脂肪酸偏好,揭示了它们在链回收中的作用.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 在Firmicutes中脂合成涉及酸,与大肠杆菌路径不同.
- 乙酸对于由PlsY.催化起来的初始乙化步骤至关重要.
- 通过两个途径合成乙酸: de novo通过PlsX和外源性脂肪酸转化通过FakAB.
研究的目的:
- 在Firmicutes中描述多个FakB蛋白质的脂肪酸偏好.
- 研究FakAB途径在脂合成和链循环中的功能.
- 分析删除FakB和FakA基因的表型后果.
主要方法:
- 构建和分析缺乏特定FakB蛋白或其组合的突变菌株.
- 具有fakA和fakB基因缺失的菌株的表型分析.
- 研究涉及FakAB通路的乙基链回收机制.
主要成果:
- 对不同Firmicute物种中各种FakB蛋白质的脂肪酸偏好的详细描述.
- 识别不同FakB对应物在基质呈现FakA中的功能作用.
- 证明 FakAB 途径在乙链的回收过程中发挥作用,特别是在缺少外源性脂肪酸的情况下.
结论:
- 坚固的脂合成依赖于通过不同的途径合成的独特的乙酸中间体.
- 多个FakB蛋白表现出特定的脂肪酸偏好,有助于途径调节.
- 在Firmicutes中,FakAB途径在链代谢和循环中发挥着重要作用.
相关概念视频
Overview of Fatty Acid Metabolism
31.7K
Lipids also are sources of energy that power cellular processes. Like carbohydrates, lipids are composed of carbon, hydrogen, and oxygen, but these atoms are arranged differently. Most lipids are nonpolar and hydrophobic. Major types include fats and oils, waxes, phospholipids, and steroids.
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
31.7K
Lipid Catabolism
167
Triglycerides serve as crucial long-term energy storage molecules in microorganisms, providing a dense source of metabolic energy. Their breakdown is mediated by lipases, which hydrolyze triglycerides into glycerol and free fatty acids. Each of these components follows distinct metabolic pathways, ultimately contributing to ATP synthesis and cellular energy homeostasis.Glycerol MetabolismGlycerol, released from triglyceride hydrolysis, is phosphorylated by glycerol kinase to form...
167
Amino Acid Catabolism
195
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
195
Fats as Energy Storage Molecules
25.7K
Triglycerides are a form of long-term energy storage molecules. They are made of glycerol and three fatty acids. To obtain energy from fat, triglycerides must first be broken down by hydrolysis into their two principal components, fatty acids and glycerol. This process, called lipolysis, takes place in the cytoplasm. The resulting fatty acids are oxidized by β-oxidation into acetyl-CoA, which is used by the Krebs cycle. The glycerol that is released from triglycerides after lipolysis...
25.7K
Other Glycolytic Pathways
220
The pentose phosphate pathway (PPP) operates in parallel with glycolysis, facilitating the metabolism of both pentoses and glucose. This pathway consists of two distinct phases: the oxidative and non-oxidative phases. While it does not directly generate ATP, the intermediates formed during the process can integrate into glycolysis, contributing to cellular energy metabolism when required.Oxidative Phase: NADPH ProductionThe oxidative phase of the pentose phosphate pathway is primarily...
220
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism
8.2K
Carboxylic acids react with alcohols to yield esters via an acid-catalyzed condensation reaction called Fischer esterification. This is a nucleophilic acyl substitution reaction that proceeds via a tetrahedral intermediate, where a water molecule is eliminated as the leaving group.
8.2K


