基于芯片技术的生物大分子晶体高效数据采集

摘要

X射线晶体学技术目前仍然是解析生物大分子结构的最主要手段,获得尺寸足够大的大分子晶体仍然是晶体学技术的难点.小晶体相对于大晶体较容易获得,而且晶格堆积较好,但小晶体容易受到辐射损伤,即使在低温下进行数据采集也很难从一颗晶体获得完整的结构信息.利用激光光刻技术制作用于多颗晶体上样的芯片,实现高通量的多颗晶体衍射数据收集,将多套数据进行合并,获得无明显辐射损伤的生物大分子结构信息.石英芯片背景散射低,上样效率高.基于芯片的晶体上样技术为晶体学研究者提供了一种利用微聚焦光束线站进行小晶体衍射数据收集并获得无明显辐射损伤高质量衍射数据的高效手段.%[Background] X-ray crystallography is still the most important means of obtaining atomic resolution structure of biological macromolecules. Obtaining protein crystals of sufficient size is the bottleneck of crystallography. Small crystals are easier to obtain than large crystals, and lattice packing is better. But small crystals are susceptible to radiation damage, and it is difficult to obtain complete structural information from a crystal even when data collection is performed at low temperatures. [Purpose] This paper aims to propose a method for acquiring small crystal data based on chip techniques at a microfocus beam line station of synchrotron radiation light source. [Methods] First of all, the chip was fabricated by laser lithography technology, and crystal was able to be deposited in the groove of the chip. Then, high-throughput data collection for diffraction of multi-crystals on the chip was achieved on the chip, and collected multiple chips data sets were emerged to get structure information of biological macromolecules. Finally, the feasibility of chip-based sample delivery method was verified by using the lysozyme crystal at the microfocus beamline (BL18U1) of SSRF. [Results] The quartz chip has low background scattering and high sample delivery efficiency. The structure of lysozyme with high resolution of 0.139 nm was obtained by chip loading and data acquisition. [Conclusions] The chip-based polycrystalline data acquisition method can obtain complete biomacromolecule structural information without obvious radiation damage by merging multiple data sets.