Miki Senda
High Energy Accelerator Research Organization (KEK), Japan
Title: Crystallization strategy when no crystals are obtained in the initial screening
Biography
Biography: Miki Senda
Abstract
Protein crystallography is an indispensable tool in the pharmaceutical and biochemical sciences. Refi nements of the protein
crystallography beam lines and their integrated programs for crystal structure analysis allow us to perform automatic or
semi-automatic structural determinations using well-diff racted crystals. However, the production of well-diff racted crystals
is still a bottleneck, even when using crystallization robots and common screening kits. Th e process of protein crystallization
does not follow a standardized, routine protocol, except in the case that good crystals are obtained at an initial crystallization
screening. In the more frequent case that no crystals or only poor crystals appear at the initial screening, there is no general
consensus regarding the next step. Nonetheless, even in the absence of well-diff racted crystals at an initial screening, it is still
possible to optimize the crystallization conditions based on the accumulated data from a wide range of protein-crystallization
attempts. Th e more such crystallization data are available, the more appropriate and effi cient optimization will be possible,
since the crystallization conditions diff er for each protein. Th erefore, at our laboratories, we are currently trying to accumulate
many experiences of protein crystallization and crystal quality improvement of poor crystals through collaboration with not
only academia but also with pharmaceutical companies. Here, we present our strategy for the effi cient generation of good
quality crystals and the successful application of our crystal quality improvement method to histone chaperone TAF-Ibeta,
the CagA oncoprotein from Helicobacter pylori and GTP sensor PI5P4Kbeta. We believe that our strategy will be applicable to
other proteins as well.