Searches for structures in the specified resolution range. A histogram icon next to the search box links to a histogram that shows the distribution of resolution in the PDB.
Searches for structures in the specified R factor range. R factor is the measure of the agreement between the structural model and the experimental diffraction data.
When solving the structure of a protein, the researcher first builds an atomic model and then calculates a simulated diffraction pattern based on that model.
The R factor measures how well the simulated diffraction pattern matches the experimentally-observed diffraction pattern. A totally random set of atoms will give an R factor
of about 0.63, whereas a perfect fit would have a value of 0. Typical values are about 0.20.
See the "Looking at Structures: Resolution" page (here) for more details.
Note: non-diffraction methods such as NMR do not have a resolution specified.
The R factor search supports four types of metrics:
Search for structures with an R free values between 0.18 and 0.24
"R free": Enter "Between: 0.18 and 0.24
Search for structures with an R free value of up to and including 0.22.
"R free": Leave the left box empty and enter 0.22 into the right box
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