枝分かれしたポリマープレヌクレーション・アセンブリは,カルシウム・リン酸の降雨を開始する

Ertan Turhan^1,2, Ieva Goldberga³, Christopher Pötzl^1,2

¹Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 38, Vienna 1090, Austria.

Journal of the American Chemical Society

|September 4, 2024

まとめ

カルシウムリン酸 (CaP) の結晶化は,古典的な核化ではなく,溶解性前核化種で始まります. 枝分かれしたポリマー組は,イオン比によって制御可能な無形カルシウムリン酸球に変形します.

科学分野:

バイオミネラル化
材料科学
結晶化

背景:

カルシウムリン酸 (CaP) の形成は,伝統的な核形成成長モデルから逸脱する.
溶解性プレヌクレーション種は役割がありますが,その性質は十分に理解されていません.

研究の目的:

核形成前の段階からCaP結晶化を包括的に特徴づける.
溶液状態の前駆体の構造的特徴,安定性,変換を明らかにする.

主な方法:

統合された時間解像度 NMR,タービドメトリー,SAXS,冷凍TEM,およびカルシウム電位計.
プレヌクレーションクラスター (PNC) とポリマーアセンブリの役割を調査した.

主要な成果:

枝分かれしたポリマー組を無形カルシウムリン酸 (ACP) 球に変換することによって開始されるCaP核化.
枝分かれした種は,しばしば検出できませんが,SAXSによって証明され,ACP形成に先行しています.
鉱化経路はCa2+/Pi比によって制御され,一時的な種の寿命が延長されます.

結論:

CaP結晶化には,枝分かれしたポリマー組成を含む複雑な中間物質が含まれています.
特定の領域の解消と濃縮によって形成される.
鉱化経路の運動制御は,イオン比率の操作によって達成可能である.

さらに関連する動画

11:42

Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers

Published on: June 20, 2019

7.8K

10:12

Flash NanoPrecipitation for the Encapsulation of Hydrophobic and Hydrophilic Compounds in Polymeric Nanoparticles

Published on: January 7, 2019

22.0K

関連する概念動画

00:57

Cationic Chain-Growth Polymerization: Mechanism

2.3K

The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...

2.3K

01:04

Anionic Chain-Growth Polymerization: Mechanism

2.0K

The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...

2.0K

01:20

Anionic Chain-Growth Polymerization: Overview

2.1K

The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...

2.1K

01:09

Radical Chain-Growth Polymerization: Mechanism

2.5K

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...

2.5K

01:42

Actin Polymerization

6.4K

Actin polymerization occurs through the head-to-tail association of binding sites on monomeric actin or G-actin to form filamentous or F-actin. The polymerization can be divided into three phases ̶ nucleation, elongation, and steady-state phase.
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight...

6.4K

01:14

Generation of Straight or Branched Actin Filaments

2.9K

The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...