Once a 3-D protein is created, there are many ways to characterize its shape. Finally, there's the fact that proteins are not visible, not even in theory. This one is a corker. This leaves scientists using tools like X-rays to try to understand the structure, without being able to observe proteins directly. 1GLN is a a protein that helps create other molecules.
Proteins exist in a world of intricate circularity.
Primary, secondary, and tertiary structure all in one diagram. Image 2 is another view of the same protein, this time with the alpha helices shown as real helices, and directional arrows mapped onto them in a way that adds to molecular layout of the protein. This view makes it easier to see some of the finer aspects of the proteins layout, but at the expense of the concreteness of the overall shape conveyed by Image 1. As every carpenter knows, all tools are bad for something, and each image here heightens the sense of some aspect of protein structure at the expense of another aspect. Primary structure, or a list of the amino acids in order, is an atomized view, while secondary and especially tertiary structures are more holistic views.