Journal
JOURNAL OF BIOMOLECULAR NMR
Volume 44, Issue 4, Pages 213-223Publisher
SPRINGER
DOI: 10.1007/s10858-009-9333-z
Keywords
Heteronuclear chemical shift; Secondary structure; Order parameter; Dynamics; TALOS
Categories
Funding
- Intramural Research Program of the NIDDK
- NIH
- NIH [P41RR02301, P41GM66326]
Ask authors/readers for more resources
NMR chemical shifts in proteins depend strongly on local structure. The program TALOS establishes an empirical relation between C-13, N-15 and H-1 chemical shifts and backbone torsion angles I center dot and psi (Cornilescu et al. J Biomol NMR 13 289-302, 1999). Extension of the original 20-protein database to 200 proteins increased the fraction of residues for which backbone angles could be predicted from 65 to 74%, while reducing the error rate from 3 to 2.5%. Addition of a two-layer neural network filter to the database fragment selection process forms the basis for a new program, TALOS+, which further enhances the prediction rate to 88.5%, without increasing the error rate. Excluding the 2.5% of residues for which TALOS+ makes predictions that strongly differ from those observed in the crystalline state, the accuracy of predicted I center dot and psi angles, equals +/- 13A degrees. Large discrepancies between predictions and crystal structures are primarily limited to loop regions, and for the few cases where multiple X-ray structures are available such residues are often found in different states in the different structures. The TALOS+ output includes predictions for individual residues with missing chemical shifts, and the neural network component of the program also predicts secondary structure with good accuracy.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available