Nanometer-resolution structural analysis of eukaryotic cells by coherent X-ray diffraction microscopy

2014 Fiscal Year Final Research Report

• Project/Area Number: 25891033
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Cell biology
• Research Institution: The Institute of Physical and Chemical Research
• Principal Investigator: TAKAYAMA Yuki 独立行政法人理化学研究所, 放射光科学総合研究センター, 基礎科学特別研究員 (40710132)
• Project Period (FY): 2013-08-30 – 2015-03-31
• Keywords: X線回折イメージング / 凍結水和試料 / 細胞・オルガネラ / 構造解析 / X線自由電子レーザー

Outline of Final Research Achievements

Biological cells and organelles are essential for lives. An understanding of their physicochemical functions requires visualization of internal structures of whole cells and/or organelles as close to the native state as possible at high resolution. In this study, we conducted structural study of chloroplasts with a size of 1 micron by cryogenic coherent X-ray diffraction microscopy using X-ray free electron laser. Development of a sample preparation method and a measurement scheme allows efficient diffraction data collection, and we have succeeded in visualization of internal structures of chloroplasts at a resolution of 70 nm. We have also proposed a method to enhance weak diffraction signals from biological samples and to achieve robust phasing, and demonstrated that resolution can be improved by a factor of two or more from a set of calculation based on current experiments.

Free Research Field

生物物理学