Advances and problems in protein
crystallography
P. Řezáčová1,2
1Institute
of Molecular Genetics AS CR, Vídeňská 6,
2Institute
of Organic Chemistry and Biochemistry AS CR, Structural Biology, Flemingovo
nam.2, Prague 6,
rezacova@img.cas.cz
Since the first protein structure was
determined in 1958, the protein crystallography field has undergone enormous
progress and development. In this paper, the current state and future
development of protein crystallography is reviewed and discussed.
The rate of structure determination has accelerated mainly due to the
introduction of new algorithms and computer programs for diffraction data
collection, structure solution, refinement, and presentation. The data collection
process with current X-ray sources, detectors and computer software is one of
the easiest and most automated steps in protein crystallography. Using
cryocooled protein crystals reduces the problem of radiation damage, and high
intensity synchrotron radiation allows data collection from smaller protein
crystals which were previously unusable. Also, phasing procedures have evolved
dramatically in recent years. With accurately measured diffraction data, use of
anomalous signal for phase estimation is possible. The availability of many
different protein fold models allows use of molecular replacement for about half of
all structures currently deposited in the Protein Data Bank (PDB). Advances in
computer software for model building and refinement as well as computer
graphics allow for user-friendly and even automatic model building and
refinement.
The achievements of protein crystallography
would be very limited without advances in molecular biology techniques of
protein preparation and characterization. Many techniques of protein
crystallization are now available and used for performing crystallization
trials in small volumes and automatic extensive screening of multitudes of
initial crystallization conditions. Still, a major bottleneck remains in the preparation
of well diffracting protein crystals.
Author’s research was supported by project
no. AV0Z50520514 and AV0Z40550506 awarded by the Academy of Sciences of the
Czech Republic. The author thanks Devon Maloy for critical proofreading.