相关实验视频

Updated: May 4, 2026

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

Published on: January 26, 2012

在循环氨基酸生物合成过程中,由非海姆铁酶进行神秘化

Frédéric H Vaillancourt¹, Ellen Yeh, David A Vosburg

¹Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.

|August 27, 2005

概括

研究人员发现了新的酶,CmaB和CmaC,生物化和循环化合物. 这一发现揭示了在天然产品生物合成中形成环环的新机制.

科学领域:

生物化学生物化学
酶学是一种酶学.
自然产品生物合成自然产品生物合成

背景情况:

在生物合成过程中,超过4000种天然产品包含素 (,,).
化显著影响这些天然产品的生物活性.
催化未激活的阿里法基的化酶仍然没有表征.

研究的目的:

描述参与冠胺酸 (CMA) 生物合成的新型酶.
在CMA合成中阐明环环形成的机制.
确定第一个已知的原酶酶,它对未被激活的阿利法基产生作用.

主要方法:

研究了来自Pseudomonas注射器的五种蛋白质 (CmaA,CmaB,CmaC,CmaD,CmaE) 的活性.
利用生物化学分析来确定CMA构造中的酶功能.
描述了CmaB作为非海姆Fe2+),阿尔法-甲酸依赖酶和CmaC作为环烯形成酶.

主要成果:

确定了CmaB作为其类中第一个表现出酶活性的酶,特别是在玛位置化l-allo-isoleucine.
证明CmaC可催化马化中间体从马化中间体形成环烯基环.
确定CmaB和CmaC的作用是连续的:马化,然后是分子内马消除.

结论:

CmaB和CmaC的联合作用代表了一种新的生物策略,通过化和消除来形成环的环.
这项研究描述了以前未知的酶,并扩大了对酶多样性和功能的理解.
这些发现提供了关于植物毒素如冠状腺素的生物合成的见解.

更多相关视频

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron

Published on: August 12, 2019

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

相关概念视频

Protein Transport to the Stroma

Protein Transport to the Stroma

Chloroplasts are triple membrane structures with an outer membrane, an inner membrane, and a thylakoid membrane, each containing distinct metabolite transporters, membrane translocons, and enzymes. Appropriate sorting and translocating these proteins to their correct membrane systems is essential for chloroplast function.
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...

Allosteric Proteins-ATCase

Allosteric Proteins-ATCase

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...

Acid Halides to Amides: Aminolysis

Acid Halides to Amides: Aminolysis

Aminolysis is a nucleophilic acyl substitution reaction, where ammonia or amines act as nucleophiles to give the substitution product. Acid halides react with ammonia, primary amines, and secondary amines to yield primary, secondary, and tertiary amides, respectively.
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...

Amino Acid Catabolism

Amino Acid Catabolism

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...

Carbon-dioxide Fixation

Carbon-dioxide Fixation

Carbon dioxide fixation in prokaryotes enables the assimilation of inorganic carbon into organic molecules, supporting biosynthetic pathways, sustaining ecosystems, and contributing to the global carbon cycle. It also has industrial applications in carbon capture and bioproduct synthesis. Autotrophic organisms rely on this process to utilize CO₂ as a carbon source in diverse environments.The Calvin CycleThe Calvin cycle is the most widespread carbon fixation mechanism, primarily used by...

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...