I have found a protein that I might use for my protein portrait. It is 1B5L an ovine protein. I have also attached the image of myoglobin from the home page of the site. It is this kind of representation of the structure that I will most likely be using. As you can see the alpha helices of the protein are represented as large tubes and areas without the defined secondary structure are smaller tubes.
Protein artists
Protein science
Studio tricks and materials