Insulin Structure
"
The structure of proinsulin (top) and insulin (bottom). Note that with removal of two pairs of basic amino acids (blue), that proinsulin is converted into insulin and C-peptide. "
http://bio.bio.rpi.edu/Parsons/Universal%20Files/Lectures/L32Insulin/32bLect.html
courtesy of Robert H. Parsons, Ph.D., Rensselaer Polytechnic Institute, used with permission
