相关实验视频
Updated: Jul 17, 2026

15:52
Postproduction Processing of Electrospun Fibres for Tissue Engineering
Published on: August 9, 2012
的循环和发针类复合物
Michael M Rosenblatt1, David L Huffman, Xiaotang Wang
1School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|October 17, 2002
概括
研究人员开发了新的循环,它比单独的histidine强化结合heme的500万倍. 这些工程化-复合体表现出增强的稳定性和独特的合作结合特性.
科学领域:
- 生物化学 生物化学
- 超分子化学 超分子化学
- 酸科学 酸科学
背景情况:
- 血红复合体在生物系统中至关重要.
- 设计稳定和功能性的合成类似物仍然是一个挑战.
- 极简主义体设计为复杂的形成提供了简化的方法.
研究的目的:
- 通过循环和针头来合成和表征新型血红复合物.
- 为了比较这些循环/针头类的结合亲缘关系和特性与它们的线性类似物.
- 研究血结合的机制和由此产生的复合物的结构特征.
主要方法:
- 线性,针头和循环两性的合成,其中中心为heme结合的histidine.
- 二硫化物键形成以创建循环和发针结构.
- 循环二极化 (CD) 光谱法用于确定螺旋性.
- 核磁共振 (NMR) 光谱用于结构和结合机制分析.
- 电化学测量以确定氧化还原潜力.
主要成果:
- 循环和针头表现出显著增强的血结合亲和力 (高达5×106倍强于histidine).
- CD研究证实了循环胺血复合体中完全的α-helicity.
- 核磁共振揭示了线性中的顺序结合,形成高旋转中间体,与循环中的合作性,低旋转复合体形成形成形成对比.
- 电化学分析显示FeIII (((coproporphyrin-I) +复合物的低氧化还原潜力.
结论:
- 与二硫化物结合的循环为血红素结合提供了强大而高效的支架.
- 工程循环结构使得合作性血结合成为可能,从而产生独特的电子性质.
- 这些发现推进了可调节功能的合成血红蛋白仿真生物的设计原则.
相关概念视频
PCR
Overview
Radical Chain-Growth Polymerization: Overview
Chain-growth or addition polymerization is successive addition reactions of monomers with a polymer chain. In radical chain-growth polymerization, the reaction proceeds via a free-radical intermediate. The free radical is formed from radical initiators, which spontaneously generate free radicals by homolytic fission. Organic peroxides (such as dibenzoyl peroxide, as shown in Figure 1) or azo compounds are popular radical initiators. A low concentration ratio of radical initiator to monomer is...
Radical Chain-Growth Polymerization: Mechanism
The radical chain-growth polymerization mechanism consists of three steps: initiation, propagation, and termination of polymerization. The polymerization initiates when a free radical generated from the radical initiator adds to the unsaturated bond in the monomer. The unpaired electron of the free radical and one π electron in the unsaturated bond creates a σ bond between the free radical and the monomer. As a result, the other π electron in the unsaturated bond converts this species into the...
Radical Chain-Growth Polymerization: Chain Branching
The skeletal structure of polymers synthesized via radical polymerization is always branched. For example, the polymerization of ethylene by radical polymerization results in a low-density grade of polyethylene with a heavily branched skeletal structure. Here, the radical site abstracts hydrogen from the growing chain, and the radical site shifts from the end (a primary carbon center) to anywhere within the growing chain (a secondary carbon center). Consequently, the part of the chain from the...
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...
Pericyclic Reactions: Introduction
Pericyclic reactions are organic reactions that occur via a concerted mechanism without generating any intermediates. The reactions proceed through the movement of electrons in a closed loop to form a cyclic transition state, where rearrangement of the σ and π bonds yields specific products.
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic rearrangements are...
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic rearrangements are...

