National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R35 GM128867
米国
引用
ジャーナル: IUCrJ / 年: 2020 タイトル: Atomic structures determined from digitally defined nanocrystalline regions. 著者: Marcus Gallagher-Jones / Karen C Bustillo / Colin Ophus / Logan S Richards / Jim Ciston / Sangho Lee / Andrew M Minor / Jose A Rodriguez / 要旨: Nanocrystallography has transformed our ability to interrogate the atomic structures of proteins, peptides, organic molecules and materials. By probing atomic level details in ordered sub-10 nm ...Nanocrystallography has transformed our ability to interrogate the atomic structures of proteins, peptides, organic molecules and materials. By probing atomic level details in ordered sub-10 nm regions of nanocrystals, scanning nanobeam electron diffraction extends the reach of nanocrystallography and in principle obviates the need for diffraction from large portions of one or more crystals. Scanning nanobeam electron diffraction is now applied to determine atomic structures from digitally defined regions of beam-sensitive peptide nanocrystals. Using a direct electron detector, thousands of sparse diffraction patterns over multiple orientations of a given crystal are recorded. Each pattern is assigned to a specific location on a single nanocrystal with axial, lateral and angular coordinates. This approach yields a collection of patterns that represent a tilt series across an angular wedge of reciprocal space: a scanning nanobeam diffraction tomogram. Using this diffraction tomogram, intensities can be digitally extracted from any desired region of a scan in real or diffraction space, exclusive of all other scanned points. Intensities from multiple regions of a crystal or from multiple crystals can be merged to increase data completeness and mitigate missing wedges. It is demonstrated that merged intensities from digitally defined regions of two crystals of a segment from the OsPYL/RCAR5 protein produce fragment-based solutions that can be refined to atomic resolution, analogous to structures determined by selected-area electron diffraction. In allowing atomic structures to now be determined from digitally outlined regions of a nanocrystal, scanning nanobeam diffraction tomography breaks new ground in nanocrystallography.
凍結剤: NITROGEN / 試料ホルダーモデル: OTHER / 最高温度: 110 K / 最低温度: 100 K
撮影
平均露光時間: 0.025 sec. / 電子線照射量: 1 e/Å2 / フィルム・検出器のモデル: GATAN K2 IS (4k x 4k) / Num. of diffraction images: 2496 / 撮影したグリッド数: 1 / 実像数: 2496 詳細: Images were collected in diffraction mode at 400 frames per second.
電子光学装置
球面収差補正装置: The TEAM1 microscope is double aberration-corrected.