The Protein Wrangler  Exploring science in the Texas Medical
Center with Carl Carruthers  Chain, Chain, Chain….   Continuing
from the last entry, I am discussing what a protein is and how
it is structured. A brief recap: the building blocks of a
protein are amino acids. There are four layers of structure:
primary, secondary, tertiary and quaternary. Primary Structure:
Individual amino acids hold hands and make a chain and it’s the
specific order of the amino acids in the chain that gives each
protein its identity. Now on to Secondary Structure!  Secondary
Structure: The first figure below shows a four amino acid chain
named CARL. This is because it consists of the following amino
acids: Cysteine, Alanine, aRginine, and Leucine. For clarity,
the second figure below is (hide the children!!) a bare naked
CARL without all the fancy side chain decorations. Looking at
the naked CARL, you can see that between each side chain (i.e.
the green part of Alanine and the magenta part of Arginine) are
the letters O and NH i