Leucine Zipper

The leucine zipper, PDB ID:2ZTA is a protein motif in which two parallel alpha helices coil around each other, with the nonpolar leucines and isoleucines facing the interior between the two helices. The fit has been described as "knobs-in-holes".

In 2ZTA, the two helices have the same sequence, and the backbone conformations are nearly identical, but the side chains have different conformations. In particular, N16 is oriented so that the NH2 from one helix hydrogen bonds to the C=O of N16 from the other helix. Salt bridges outside of the core also differ on each helix.

The .STL file contains both helices, so two separate pieces will result from the print. They will fit nicely together but will not hold together on their own.

Created from the PDB file using VMD and netfabb basic.

http://www.rcsb.org/pdb/explore/explore.do?structureId=2zta

Your students can build their own paper model of this structure! My book "Molecular Origami for Biochemistry" is available from http://