Flow enhanced protein crystallization at the air/water interface

CBET-0755968 Hirsa描述和使用蛋白质结构的能力使新药和药理学试剂的合理设计成为可能。通过对蛋白质和核酸的详细结构研究，在分子水平上对生物系统的理解取得了许多进展。然而，蛋白质必须首先结晶，以使用产生其结构的精确描述的技术。与大量生长蛋白质晶体相比，2D蛋白质结晶大大简化了蛋白质研究的理论和实验方面。例如，2D系统不受重力的影响，这个问题困扰着晶体学家，没有负担得起的补救措施。在空气/水界面处的二维蛋白质结晶需要蛋白质与含有配体的脂质单层的特异性结合。蛋白链霉亲和素，在溶液中，已成功地结晶在空气/水界面，其中含有配体，生物素的脂质单层，已蔓延。链霉亲和素和生物素之间的强亲和力在合适的条件下在界面处引发晶体形成。PI将研究由地板恒定旋转驱动的固定开口圆柱体组成的系统中的流动效应，在广泛的雷诺数范围内的轴对称流态。PI最近发现，在不会发生结晶的条件下，被流动剪切的界面可以诱导结晶。研究人员发现，流动也可以产生一种新的晶体形式，其中蛋白质分子似乎以线性阵列排列，类似于纳米线，但更长，更直。PI计划研究与这些新晶体相关的宏观流动现象。 PI期望改变雷诺数将分别调节成核速率和生长，这对晶体学家来说是一个挑战。有大量的蛋白质还没有通过常规方法成功地结晶，如果流动诱导结晶可以提高产量，那么这里的努力将是一个巨大的成功。多学科的高级团队（来自机械工程和应用数学），以其强大的生产合作记录，将提供一个极好的机会，教育研究生和本科生在一个令人兴奋的新兴领域耦合流体力学和蛋白质研究。

CBET-0755968HirsaThe ability to describe and use protein structure has enabled the rational design of new drugs and pharmacological agents. Many advances in understanding of biological systems at the molecular level have been made possible through detailed structural studies of proteins and nucleic acids. However, proteins must first be crystallized to use techniques that yield a precise description of their structure. In contrast to growing protein crystals in the bulk, 2D protein crystallization greatly simplifies both the theoretical and experimental aspects of protein studies. For example, 2D systems are not affected by gravity, an issue that plagues crystallographers with no affordable remedy. Two-dimensional protein crystallization at the air/water interface entails the specific binding of a protein to a lipid monolayer containing a ligand. The protein streptavidin, in solution, has been successfully crystallized at the air/water interface where a lipid monolayer containing a ligand, biotin, has been spread. The strong affinity between streptavidin and biotin initiates crystal formation at the interface under suitable conditions. The PIs will investigate the effects of flow in a system consisting of a stationary open cylinder driven by the constant rotation of the floor, in the axisymmetric flow regime over a wide range of Reynolds numbers. The PIs have recently discovered interface s sheared by flow can induce crystallization under conditions where none would otherwise occur. The PIs have discovered that flow can also produce a new form of crystal where the protein molecules appear to pack in a linear array, analogous to nano-wires, but much longer and perfectly straight. The PIs plan to investigate the macroscale flow phenomena associated with these new crystals. The PIs expect that varying the Reynolds number will regulate the nucleation rate and growth separately, which is a challenge for crystallographers. There are a vast number of proteins that have not been successfully crystallized by conventional means, and if flow-induced crystallization can improve the yield, then the effort here would be a resounding success. The multidisciplinary senior team (from mechanical engineering and applied mathematics), with its strong record of productive collaboration, will provide an excellent opportunity to educate graduate and undergraduate students in an exciting emerging field coupling hydrodynamics and protein studies.