I viewed the protein brain-derived neurotrophic factor (BDNF). I was surprised to see the structure derived from the crystal of the protein was a heterodimer. After discovering this little tid-bit, I wanted to see what interaction was “holding” the two peptides in the dimer. Figure 1, below illustrates the hydrogen bonding between polar residues. The most interesting interaction was with the biforkated water that hydrogen bonds with two serines; one on chain A and one on chain B. WOW!
-Kathryn Elizabeth Abrahamsson