Great expectations: structural biology, macromolecular machines and moving targets

近年来的技术发展尚无消息，在理解复杂或动态的大分子系统方面取得了巨大进步。但是正如戴维·斯图尔特（David Stuart）在首届阿斯特伯里对话，最近在利兹举行的，巨大的进步导致了相应的巨大期望。这是关于如何满足这些期望的选择性说明，如研讨会的演讲所反映。

病毒，疫苗和药物靶标

David Stuart was speaking on他在Picornaviruses上的工作– causes of much human and animal disease, perhaps most infamously polio and foot and mouth disease – and the goal of delivering vaccines and antivirals based on an understanding of the structural features and requirements of viral pathogens – a long-term aim of his lab.

面对同样的挑战，彼得·斯托克利（Peter Stockley）证明了the impact of cryo-EM on the issue of viral packaging。Virus capsids assemble around viral RNA specifically, and using cryo-EM with a battery of other techniques he has been able to identify the signals that provide this specificity and show how they do this, with a view to novel drug targets.

在一起更好

Peter Stockley’s work was just one example of a major theme of the meeting – how combining datasets from the panoply of biophysical methods – NMR, crystallography, mass spectrometry, molecular dynamics and both light and electron microscopy – which do not quite tell the full story on their own can enable data that are incomplete and may be conflicting to become informative.

三伴侣蛋白中亚基的排序是一个空旷的问题，例如，分辨率相对较低的质谱数据和晶体结构给出了不同的答案，直到the work described by Plenery speaker Michael Levitt.

三伴侣蛋白中亚基的排序是一个空旷的问题，例如，分辨率相对较低的质谱数据和晶体结构给出了不同的答案，直到the work described by Plenery speaker Michael Levitt。

He used these data to inform molecular dynamics simulations which showed that the ordering of the subunits differ from what these lower resolution data had indicated, and provide a better resolution of the structure.

他和他的同事通过他们的工作发现的结构不对称性也有助于阐明蛋白质的机制，表明类似的亚基可以扮演不同的角色：有些人“略微破裂”以绑定底物以折叠，有些则在ATPases中起作用。。

In a more obviously translational application,Erin Cutts谈到了显微镜和分子动力学方法的结合如何使提出一种分子机制，以实现疟疾寄生虫的主要感染危害之一。

The knob-associated protein KAHRP is required for the formation of ‘knobs’ on red blood cells in malaria. These ‘knobs’ result in endothelial adhesions that prevent infected red blood cells from being swept into the spleen for clearance along with their passengers, and involve interactions of KAHRP with other parasite proteins and the red blood cell protein spectrin.

通过应用计算和显微镜检查ERIN CUTT和同事，已经能够证明蛋白质的K2域表面上的正电荷将其连接到Spectrin和细胞骨架上，以及这如何导致这些粘附的中心的螺旋结构- 引起突起。

移动目标

One of the properties of the proteins in the knob complex that makes them such a challenge is their large content of structurally disordered regions, a focus of much current interest and which have traditionally been difficult to analyze.

这些具有类似难以捉摸的特性（例如折叠中间体）的蛋白质物种已与包括分子动力学模拟的技术组合以及NMR光谱中的技术发展变得容易实现。

阿斯特伯里中心主任谢娜·拉德福德（Sheena Radford）描述了她关于淀粉样蛋白形成机制及其细胞毒性的一些调查。

例如，阿斯特伯里中心的导演谢娜·拉德福德（Sheena Radford）描述了她的一些investigations on the mechanisms of amyloid formation and its cellular toxicity。她展示了如何捕获B2微球蛋白的瞬时折叠中间体的新NMR技术可以解释为什么某些蛋白质的变体形式具有淀粉样蛋白的形式，并且六聚体聚集体可以形成和破坏细胞膜。

NMR光谱学历史上受到蛋白质大小的限制，大型复合物不提供信息光谱，but Lewis Kay showed a way round thisin how he demonstrated allostery in the regulation of the massive, and hence ‘nearly invisible’ to NMR, proteasome complex.

By specific labelling of a subset of the amino acids in the complex, NMR spectra could be generated to show how the chemical environment of these residues in one subunit of the complex changed depending on the presence of other subunits, indicating a degree of allosteric regulation and helping to understand the mechanisms of this vital cellular machinery.

NMR is more readily used to target proteins at the other end of the size spectrum, and their dynamics over time, and Anais Cassaignau used these strengths effectively in anovel strategy to study the folding process新生的搞笑域直接从核糖体with small, isotopically labelled fragments.

She showed that chemical signatures of folding of the Ig domain of FLN5 appear after significant amounts of the protein emerge from the ribosome, suggesting that folding is suppressed during translation to avoid mis-folding, and also identified some interactions between nascent chains and the surface of the ribosome which may be partly responsible for this.

‘The lazy option’

Michael Levitt claimed in his plenary talk that he chose physics as the ‘lazy option’, requiring only an understanding of principles and applying mathematics rather than memorising of pathways, chemicals and facts.

生物物理学可以看作是两全其美的最糟糕的，因为它既需要对热力学和动力学原理的理解，又要深入了解蛋白质及其领域的相互作用，然后是其与生理学的关系。但是奖励是巨大的。