Question

The detailed tertiary structure of a protein is determined by the ___________ technique.

(a) HPLC

(b) Spectrometry

(c) X-ray

(d) X-ray crystallography

I have been asked this question in unit test.

My question is taken from Biological Molecules Structures and Functions topic in chapter Structures and Functions of Biological Molecules of Cell Biology

Answer 1

The correct answer is (d) X-ray crystallography

Easy explanation: In X-ray crystallography technique, a crystal of the protein is bombarded by a thin beam of X-ray and the radiation that is scattered by the electrons of the protein’s atoms is allowed to strike a radiation sensitive plate or detector, forming an image of spots. When these diffraction patterns are subjected to complex mathematical analysis, an investigator can work backward to derive the structure responsible for producing the pattern.