Furuno T, Sasabe H
Frontier Research Program, Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
Biophys J. 1993 Oct;65(4):1714-7. doi: 10.1016/S0006-3495(93)81225-6.
A two-dimensional (2D) crystal of streptavidin has been obtained by a nonspecific binding method. The protein molecules were bound and formed a dense packing on the film of poly(1-benzyl-L-histidine) spread at the surface of protein solution. The surface film was moderately heated to stimulate crystallization of bound streptavidin. A potential of this method for obtaining 2D crystals of soluble proteins is demonstrated. The present 2D crystal structure of streptavidin resembles that previously obtained by specific binding to biotinylated lipid. We show in addition that the 2D array of protein with usual size approximately 50 A can be imaged using a high resolution scanning electron microscope (HR-SEM) and subject to structural analysis at low resolution. Various limitations in HR-SEM degrade considerably the image quality. However, the usability of a bulk plate as specimen support would make HR-SEM a convenient tool, when such a substrate must be considered in application of protein arrays, and if an intrinsic low resolution is acceptable.
通过非特异性结合方法获得了链霉亲和素的二维（2D）晶体。蛋白质分子在铺展于蛋白质溶液表面的聚（1-苄基-L-组氨酸）薄膜上结合并形成致密堆积。对表面薄膜进行适度加热以促进结合的链霉亲和素结晶。证明了该方法在获得可溶性蛋白质二维晶体方面的潜力。目前链霉亲和素的二维晶体结构类似于先前通过与生物素化脂质特异性结合获得的结构。此外，我们还表明，使用高分辨率扫描电子显微镜（HR-SEM）可以对尺寸通常约为50埃的蛋白质二维阵列进行成像，并进行低分辨率结构分析。HR-SEM中的各种限制会显著降低图像质量。然而，当在蛋白质阵列应用中必须考虑使用块状平板作为样品支撑时，并且如果内在低分辨率是可接受的，那么块状平板作为样品支撑的可用性将使HR-SEM成为一种方便的工具。
