铁基酸盐依赖氧基酶TqaL的立体选择性和基质特异性
Hui Tao1, Richiro Ushimaru1,2,3, Takayoshi Awakawa1,2,4
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan.
像TqaL这样的非血红铁酶通过一种复杂的立体化学过程从氨基酸中形成亚齐里丁. 突变生成揭示了控制反应结果和基质特异性的关键残留物.
科学领域:
- 生物化学
- 有机化学
- 酵素学
背景情况:
- 非血红素铁酶是合成复杂分子的重要生物催化剂.
- 含有Fe (II) /α-甲酸的氧化酶可以进行具有挑战性的化学转换.
- TqaL酶从L-Val中形成亚齐里丁,但其机制和合成效用尚不清楚.
研究的目的:
- 阐明TqaL催化阿齐里迪纳的机制.
- 调查TqaL的立体化学过程和基质范围.
- 确定控制酶活性和选择性的残留物.
主要方法:
- 来自L-Val的亚齐里丁产品的立体化学分析.
- 用L-Ile和L-Allo-Ile进行酶检测.
- TqaL (Ile343,Phe345) 的位点定向突变发生.
主要成果:
- 通过TqaL催化L-Val的亚齐里丁化表现出混合的立体化学反应 (保留和反转).
- 通过立体融合反应,TqaL从L-Ile和L-Allo-Ile产生相同的二聚体亚齐里丁.
- Ile343和Phe345的突变改变了反应类型 (亚齐里迪纳与化) 和立体化学结果.
- 突变的TqaL显示了对α-氨基酸氧化的增强活性.
结论:
- 获得了TqaL的立体选择性和基质特异性的机制见解.
- 对于调节TqaL的催化功能来说,Ile343和Phe345非常重要.
- TqaL及其变种在有机化学中具有合成应用的潜力.
更多相关视频
08:02Benchtop Immobilized Metal Affinity Chromatography, Reconstitution and Assay of a Polyhistidine Tagged Metalloenzyme for the Undergraduate Laboratory
Published on: August 23, 2018
12:08Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
Published on: March 18, 2012
相关概念视频
Reactions of Aldehydes and Ketones: Baeyer–Villiger Oxidation
The carbonyl center is...
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Allosteric Proteins-ATCase
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...
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
E2 Reaction: Stereochemistry and Regiochemistry
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major...
Cooperative Allosteric Transitions
