蛋白质三级结构

利用BP神经网络预测蛋白质三级结构

Prediction of Protein Structural Class by BP Neural Network

BP神经网络在蛋白质三级结构预测中能大大提高预测准确率。

BP neural network in prediction of protein tertiary structure can greatly improve predicting accuracy .

为了寻找一种更优的网络结构，本文首次将灵活神经树（FNT）应用在蛋白质三级结构预测中，PSO对网络参数进行优化，概率增强式程序进化（PIPE）对网络结构进行优化。

In order to find a better network structure , this article first uses a flexible neural tree ( FNT ) in protein tertiary structure prediction , PSO optimizes the network parameters , probabilistic incremental program evolution ( PIPE ) optimizes the network structure .

首先研究了beta-trefoil家族，该家族蛋白质三级结构都具有三重对称性。对蛋白质编码序列的研究发现，蛋白质编码序列有和蛋白质三级结构几乎一致的三重对称性。

Firstly , for beta-trefoil family , tertiary structures of this family protein are triple symmetry and through analysis of their coding sequences , the triple symmetry discovered in the coding sequence was almost as identical as the symmetry of tertiary structure of protein .

这样的结构对于维持多肽和蛋白质三级结构的稳定有重要的作用。

Such bridges are important in stabilizing the tertiary structure of peptides and proteins .

病毒蛋白质三级结构预测比较成功的是日本脑炎病毒包膜糖蛋白的三级结构。

The prediction of space structure of envelope glycoprotein of Japanese encepalitis virus was a successful sample .

很多蛋白质三级结构具有对称性，表现为蛋白质内部拥有相似的子结构片段。

Tertiary structures of many proteins are symmetrical , namely , there are similar motifs in protein .

结构域是蛋白质三级结构下面的结构层次，大多数的蛋白质都可分为若干个结构域，结构域的不同组合使蛋白质具有不同的三级结构并具有不同的功能。

Domain is a protein architecture under proteins ' tertiary structure , which can be identified in most of proteins .

针对蛋白质三级结构预测这种多分类问题，本文提出将多类问题转换成多个二分类问题的集成。

For the multi-classification problem of protein tertiary structure prediction , this paper presents transforming the multi-class problem to integration of several two classification problems .

对于蛋白质三级结构预测这种信息维数高，计算量大的问题，借助神经网络是非常有效地。

For the problem of protein structure class prediction which has the high dimensionality information and amount compute , using neural network is very effective .

一些决定蛋白质三级结构的主要的弱分子作用力为共价键，离子键，氢键，疏水键和亲水键。

Several weak molecular interactions responsible for the maintenance of tertiary structure of proteins are covalent , ionic , hydrogen , and hydrophobic or hydrophilic bonds .

蛋白质三级结构预测实际上是根据提取出的有用信息，通过学习分析这些信息，总结出规律，实现对未知结构氨基酸序列的结构预测。

Protein structure class prediction actually is based on useful information extracting from the amino acid , by studying and analyzing the information , summed up the rule , and realize the structure of the amino acid sequence of unknown structure prediction .

蛋白质的三级结构是以实验方式确定（求解）的，主要采用名为X-rayDiffraction或X-rayCrystallography的方法。

The tertiary structure of a protein is experimentally determined ( solved ), predominantly by a method called X-ray Diffraction or X-ray Crystallography .

基于RNA水解酶的实验，Anfinsen提出：蛋白质的三级结构唯一地由其氨基酸序列决定。

On the basis of studies on ribonuclease , in the mid 1950 's Anfinsen proposed that the tertiary structure of a protein is encoded in its amino acid sequence .

详细了解蛋白质的三级结构信息有助于理解其生物学功能。随着植物基因组研究的进展，已发现了50多个植物类金属硫蛋白（MetallothioneinLike，MTL）基因。

With the progress of plant genome research , more than 50 plant metallothionein_like ( MT_L ) genes have been found , but only several MT_L proteins have been detected and no experimental structural information for MT_L proteins has been reported so far .

RdRp蛋白中可变氨基酸主要位于可及性较好的蛋白分子表面，氨基酸的突变一般不影响蛋白质的三级结构和酶活性中心。

Most amino acid mutations in RdRp protein localized on protein surface with good accessibility , which could not affect the RdRp protein tertiary structure and active center .

其中在pH6.0以下，蛋白质的三级结构变得松散，荧光强度下降，pH5.0时尤为显著，以后随pH值升高其三级结构得到恢复。

It was founded that the tertiary structure loose and the intensity of fluorescence decreased below pH 6.0 . The intensity of fluorescence is lowest at pH 5.0 and the tertiary structure is reconstructed as the solution pH is increased .

蛋白质三级拓扑结构对热稳定性贡献的初步探讨

Preliminary Study on the Contribution of Protein Structure Topology to Thermostability

蛋白质的三级结构与其功能紧密耦合。

The tertiary structure of a protein is closely coupled to its function .

此外，高浓度的盐可降低酶蛋白的溶解性，盐也能破坏蛋白质的三级结构而使酶蛋白变性，而蛋白质的三级结构是酶的活动性所必需的。

In addition , high salt concentrations tend to reduce the solubility and denature enzyme proteins through disruption of the tertiary protein structure which is essential for enzymatic activity .

然而从一级序列预测蛋白质分子的三级结构并进一步预测其功能，是一项极富挑战性的工作。

However how to predict its three-dimensional conformation from its primary sequence and so to predict its function is a challenging work .

由于这些变化，NMR可系统地决定多个实例（模型）来代表同一蛋白质略有变化的三级结构。

Due to these variations , NMR methodically determines multiple instances ( models ) that represent slightly shifted tertiary structures for the same protein .

小波筛选蛋白质二/三级复合结构中的三级结构

Separation of tertiary structure from protein secondary / tertiary structural complex by wavelet analysis

所以我们能认为蛋白质中对称的三级结构是因为它们的氨基酸序列具有对称性，也就是说蛋白质的三级结构的对称性是由它的序列编码的。

So we can consider that the symmetrical tertiary structure of these proteins is the result of the amino acid sequences ' symmetry , in another word , the symmetry of the tertiary structure is encoded by the sequence .

指出了螺旋多肽链的扭曲变形结构比其均匀螺旋结构更稳定，和由螺旋多肽链的扭曲变形而产生的附加电荷间的静电吸引有助于蛋白质链折叠为三级结构。

It is shown that the twisting deformed structure of helix polypeptide chain is more stable than the uniform helix structure and the static attraction between the extra charges arising from deformation of helix polypeptide chain is advantageous to fold protein chain into the tertiary structure .

蛋白质结构预测的基本假设是蛋白质三级结构由其氨基酸序列唯一决定。

The basic assumption of protein structure prediction is amino acid sequence sole determines protein structure class .

两个家族蛋白质编码序列的对称性和蛋白质三级结构的对称性几乎一致。

Symmetry discovered in the protein-coding sequences of two families is almost identical to that of protein tertiary structures of two families .

本文主要研究内容是给定一个蛋白质序列，通过采用同源建模的方法最终预测出该蛋白质的三级结构。

This paper mainly concentrates on an aspect that we can predict three-dimensional structure of a protein which is given originally through homologous modeling .

自从安芬森的蛋白质变性-复性试验以后，越来越多的人接受了蛋白质的一级结构决定了这个蛋白质的三级结构的假定。

Since Anfinsen experiment , more and more people accepted the assumption that the primary structure of protein determines the tertiary structure of this protein .