一个甲基转移酶启动了teleocidin B生物合成中的烯循环
Takayoshi Awakawa1, Lihan Zhang, Toshiyuki Wakimoto
1Graduate School of Pharmaceutical Sciences, The University of Tokyo , Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|July 4, 2014
概括
研究人员确定了teleocidin B生物合成的基因,这是一种蛋白质激酶C激活剂. 一种新型的甲基转移酶 (tleD) 通过阴离子形成触发了类环的闭合,这是这种途径的首次.
科学领域:
- 自然产品生物合成 自然产品生物合成
- 有机化学 有机化学
- 分子生物学分子生物学
背景情况:
- 来自Streptomyces的Indole terpenoidTeleocidin B,由于其独特的结构和蛋白质激酶C激活,引起了人们的兴趣.
- 了解teleocidin B的生物合成对于其在有机化学和细胞生物学中的潜在应用至关重要.
研究的目的:
- 为了确定负责teleocidin B生物合成的基因.
- 阐明甲基转移酶基因 (tleD) 在形成合环结构中的功能.
主要方法:
- 生物合成基因的识别,包括非核糖体合成酶 (tleA),P-450单氧化酶 (tleB),先转移酶 (tleC) 和甲基转移酶 (tleD).
- 转录分析和异质表达被用来识别和表征tld基因.
- 生物化学测试以确定TleD.的酶活性.
主要成果:
- 鉴定了编码teleocidin B生物合成关键酶的基因.
- 鉴定了TleD基因,该基因与TleABC集群分离,该基因的特征.
- 已经证明,TleD可以甲基化杰拉尼尔基团,并促进基于印的循环化,形成印融合的六个环.
结论:
- 这项研究揭示了参与teleocidin B生物合成的完整基因组.
- 甲基转移酶TleD通过一种新的阴离子介导机制在类环闭合中发挥着关键作用.
- 这是第一个关于甲基化产生的阴离子在天然产品生物合成中引发连续的类环闭合的报告.
相关概念视频
Thermal and Photochemical Electrocyclic Reactions: Overview
2.1K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.1K
Thermal Electrocyclic Reactions: Stereochemistry
1.6K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
1.6K
Cycloaddition Reactions: MO Requirements for Photochemical Activation
1.7K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
1.7K
Photochemical Electrocyclic Reactions: Stereochemistry
1.4K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.4K
Biosynthesis of Lipids
959
Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis...
959
Biosynthesis in Bacteria
1.0K
Biosynthesis in bacteria is a fundamental anabolic process that generates essential macromolecules, including proteins, nucleic acids, lipids, and polysaccharides. These macromolecules are critical for cellular growth, replication, and function. The process is tightly regulated and energetically linked to catabolic pathways to ensure optimal resource utilization.Biosynthetic pathways begin with precursor metabolites such as pyruvate, acetyl-CoA, and glucose-6-phosphate derived from glycolysis,...
1.0K


