Membrane proteins remain a somewhat enigmatic group of biomolecules. On the one hand they mediate some of the most important processes in biology with molecular mechanisms that are often elegantly complex. On the other hand they are exceptionally challenging to produce, making studies of membrane protein structure and function among the most difficult projects undertaken by biochemists. The central issue with studies of a membrane protein has been the need to extract them from their native lipid environment before purification and production of a homogenous sample. Historical approaches have utilized detergent solubilisation but these often lead to a sample with low activity and stability. In the past 15 years a new approach that focuses on preserving the local lipid environment surrounding the membrane proteins has been developed. The latest, and perhaps most complete, incarnation of this method has been the use of polymers based on styrene maleic acid (SMA) to stabilise nanoscale discs of lipid that contain membrane proteins. In this review we examine the range of SMA-related polymers that have now been shown to have utility in the production of membrane proteins. We discuss the differences between the polymers and attempt to discover rules and trends that explain their behavior.

中文翻译：

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纯化不含传统洗涤剂的膜蛋白：SMA、新聚合物、新机遇和新见解

膜蛋白仍然是一组有点神秘的生物分子。一方面，它们通过通常非常复杂的分子机制来调节生物学中一些最重要的过程。另一方面，它们的生产极具挑战性，使膜蛋白结构和功能的研究成为生物化学家承担的最困难的项目之一。膜蛋白研究的核心问题是在纯化和生产同质样品之前需要从它们的天然脂质环境中提取它们。历史方法使用洗涤剂增溶，但这些方法通常会导致样品活性和稳定性低。在过去的 15 年中，已经开发出一种新方法，其重点是保护膜蛋白周围的局部脂质环境。最新的，也许最完整的方法是使用基于苯乙烯马来酸 (SMA) 的聚合物来稳定含有膜蛋白的纳米级脂质盘。在这篇综述中，我们研究了 SMA 相关聚合物的范围，这些聚合物现已被证明可用于生产膜蛋白。我们讨论聚合物之间的差异，并试图发现解释它们行为的规则和趋势。