炭病致死因の早期転移に対するプロトネーションの影響:分子動力学シミュレーションとマイルストーニング理論からの動力学
Piao Ma1, Alfredo E Cardenas2, Mangesh I Chaudhari3
1Department of Chemistry, University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|October 12, 2017
まとめ
分子ダイナミクスシミュレーションは,致死因 (LF) のN端段が炭菌経路にどのように浸透するかを明らかにします. プロトネーション状態は,この初期,潜在的に不可逆的なステップを決定的に影響し,チャネルブロックフックを形成します.
科学分野:
- バイオ物理学
- コンピューター生物学
- 生物化学
背景:
- 死因因子 (LF) は炭毒素の重要な成分です.
- 炭菌経路でのLF転移の理解は,対策策の開発に不可欠です.
- LFのN端セグメントが浸透プロセスを開始します.
研究 の 目的:
- 炭菌経路を通してLFのN端段の浸透の分子メカニズムを調査する.
- この過程におけるアミノ酸のプロトネーション状態の役割を解明する.
- 先進的なシミュレーション技術を使用して,浸透に関する運動情報を抽出します.
主な方法:
- 分子ダイナミクスの詳細なシミュレーション
- 明らかに溶媒のモデル
- 複数の時間スケール (ナノ秒からミリ秒) にわたる運動分析のためのマイルストーニング理論.
主要な成果:
- 構造化されていないN端鎖はLFの浸透を誘導する.
- 初期浸透は,アミノ酸の陽子化状態に対して非常に敏感である.
- 高プロトネーション状態は,チャネルとフィ (φ) クランプを通過することを容易にします.
- 最初の浸透は不可逆であり,チャネル口で"フック"を形成する.
結論:
- プロトネーションに依存する初期浸透は,LF転移の重要なボトルネックです.
- このメカニズムは炭毒素の活性を抑制する標的となる可能性があります.
- シミュレーションは,膜経路を通してタンパク質の浸透のダイナミクスについての洞察を提供します.
関連する概念動画
02:55Temperature Dependence on Reaction Rate
77.9K
The Collision Theory
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
77.9K
03:06Reaction Mechanisms
24.5K
Chemical reactions often occur in a stepwise fashion, involving two or more distinct reactions taking place in a sequence. A balanced equation indicates the reacting species and the product species, but it reveals no details about how the reaction occurs at the molecular level. The reaction mechanism (or reaction path) provides details regarding the precise, step-by-step process by which a reaction occurs.
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
24.5K
03:08Rate-Determining Steps
30.5K
Relating Reaction Mechanisms
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
30.5K
01:19Impact Loading
979
Impact loading occurs when a moving object collides with a stationary structure, such as a rod with a uniform cross-sectional area fixed at one end. Under these conditions, the rod absorbs the kinetic energy from the striking object, leading to deformation and subsequent stress development. As the rod returns to its original position and reaches maximum stress, the absorbed energy, initially manifested as kinetic energy, transforms entirely into strain energy.
In cases of elastic deformation,...
In cases of elastic deformation,...
979
01:24The Kinetic Model of Gases
160
The kinetic model of gases explains the properties of a perfect gas using three main assumptions: molecules move in ceaseless random motion, their size is negligible compared to the distances between them, and they do not interact except during perfectly elastic collisions. The total energy of a gas is the sum of the kinetic energies of all its constituent molecules. The pressure exerted by the gas arises from the continual bombardment of the container walls by billions of colliding molecules.
160
01:28Logarithmic Differentiation
181
When a car’s weight and driving forces act on a tire, they impose an external load on the rubber material. This load is resisted internally by forces distributed throughout the tire structure, which are defined as stress. The resulting deformation of the rubber due to this stress is quantified as strain. The relationship between stress and strain governs how the tire deforms under load and is central to understanding its mechanical response during operation.Rubber exhibits a nonlinear...
181