 |
 |
I have this question. For exmaple, a protein could be crystallized in two crystal forms. Two crystal form have same space group, and 1 molecule/asymm. One crystal form diffracts to 3A with 50% solvent; and the other diffracts to 3.6A with 80% solvent. The cell volume of 3.6A crystal must be 5/2=2.5 times larger because of higher solvent content. If both data collecte to same completeness (say 100%), 3.6A data actually have higher data/parameter ratio, 5/2/(3.6/3)**3= 1.45 times to 3A data. For refinement, better data/parameter should give more accurate structure, ie. 3.6A data is better. But higher resolution should give a better resolved electron density map. So which crystal form really give a better (more reliable and accurate) protein structure?