Image caption: An approach combining terahertz spectroscopy, X-ray diffraction, and solid-state density functional theory was utilized to accurately measure the elasticities of poly-l-proline helices by probing their spring-like vibrational motions. In their communication (DOI: 10.1002/anie.201602268), T. M. Korter and co-workers reveal that poly-l-proline is less rigid than commonly expected, and that the all-cis and all-trans helical forms exhibit significantly different Young’s moduli.
As was the case for the first ChemMedChem December, 2007 cover issue (posted previously), the cover story in this month’s issue is a communication by myself and members and collaborators of the Robert Doyle Group here at Syracuse University. In this case, the work for the cover image actually went into computational research published in the associated article (instead of just a pretty cover image to complement the associated article, which was the intent of the previous cover).
The image below shows the Transcobalamin II (TCII) protein (in teal ribbons, with a bound cyanocobalamin (B12) shown in red. The PDB code for this complex is 2BB5) sitting within the surface-accessible fragment of the gigantic insulin receptor (PDB code 2DTG. The cell membrane would be at the bottom of this image, with the remainder of the complete protein sitting both within the cell membrane and then into the cytoplasm). Saving the lead-up to this structure generation for the associated published article, this image was created to show one of the most important steps in the Oral Insulin project being worked on in the Doyle Group, with the fact that we know it works making the validity of the image content all the more relevant. In brief, this figure shows that the TCII/B12-Insulin complex can fit within the insulin receptor such that the insulin molecule can bind to its receptor position on the appropriately described insulin receptor (IR), thereby instigating the cascade of events that leads to cellular glucose uptake.
For a larger view, click on the image.