PT  - JOURNAL ARTICLE
AU  - Julia Koehler Leman
AU  - Andrew R. D’Avino
AU  - Yash Bhatnagar
AU  - Jeffrey J. Gray
TI  - Comparison of NMR and crystal structures of membrane proteins and computational refinement to improve model quality
AID  - 10.1101/127142
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 127142
4099  - http://biorxiv.org/content/early/2017/04/13/127142.short
4100  - http://biorxiv.org/content/early/2017/04/13/127142.full
AB  - Membrane proteins are challenging to study and restraints for structure determination are typically sparse or of low resolution because the membrane environment that surrounds them leads to a variety of experimental challenges. When membrane protein structures are determined by different techniques in different environments, a natural question is “which structure is most biologically relevant?” Towards answering this question, we compiled a dataset of membrane proteins with known structures determined by both solution NMR and X-ray crystallography. By investigating differences between the structures, we found that RMSDs between crystal and NMR structures are below 5 Å in the membrane region, NMR ensembles have a higher convergence in the membrane region, crystal structures typically have a straighter transmembrane region, have higher stereo-chemical correctness, and are more tightly packed. After quantifying these differences, we used high-resolution refinement of the NMR structures to mitigate them, which paves the way for identifying and improving the structural quality of membrane proteins.