Which is evidence that structures for proteins determined by X-ray crystallography represent the structures in solution?
A)Their similarity to structures determined by NMR.
B)The protein crystals are soluble in water.
C)The proteins must align in a regular pattern to form a crystal.
D)Only one conformation is ever possible for a protein so it is irrelevant whether the protein is in a crystal or in solution.

Question

Quizplus · Accepted Answer

The similarity between structures determined by X-ray crystallography and NMR suggests that the structures determined by X-ray crystallography are representative of structures in solution. NMR also provides information about the structure of proteins in solution. The solubility of protein crystals in water (B) is not relevant to the accuracy of the structures determined by X-ray crystallography, as the crystal is a solid state and not a solution. The alignment of proteins in a regular pattern to form a crystal (C) is necessary for the determination of the X-ray crystallography structure but does not necessarily indicate that the structure is representative of the protein in solution. (D) is also incorrect as proteins can exist in different conformations in solution depending on factors such as pH, temperature, and binding to ligands.

Which Is Evidence That Structures for Proteins Determined by X-Ray