Displayed here is a peptide segment that is present in many fibroin proteins that are found in silk fibers. It is repeated many times to make up the ordered, repetitive structure of the crystalline domain of the fibroin. The labels describe how additional units of the hexapeptide are added to the ends of this peptide segment.
Determine the sequence of the segment by hovering over the residues taking time to consider the nature of their side chains and from which direction their side chains project from the backbone.
