CheShift

CheShift-2

Stable release	3.0 / 1 September 2013
Written in	Python, HTML
Operating system	Cross-platform
Available in	English
Type	Bioinformatics
License	Free of charge for academic use
Website	cheshift.com

CheShift-2 (pronounced /tʃeʃɪft/) is an application created to compute ¹³C^α and ¹³C^β protein chemical shifts and to validate protein structures. It is based on quantum mechanics computations of ¹³C^α and ¹³C^βchemical shift as a function of the torsional angles (φ, ψ, ω and χ¹, χ²) of the 20 amino acids.

CheShift-2 can return a list of theoretical chemical shift values from a PDB file. It also can display a 3D protein model based on an uploaded PDB file and chemical shift values. The 3D protein model is colored using a five color code indicating the differences of the theoretical vs the observed chemical shifts values. The differences between observed and predicted ¹³C^α and ¹³C^β chemical shifts can be used as a sensitive probe with which to detect possible local flaws in protein structures.^[1] If both ¹³C^α and ¹³C^β observed chemical shifts are provided CheShift-2 will attempt to provide a list of alternative χ1 and χ2 side-chain torsional angles that will reduce the differences between observed and computed chemical shifts, these values can be used to repair flaws in protein structures.^[2]

CheShift-2 can be accessed online at http://www.cheshift.com, or via PyMOL plugin.

See also

• Structure validation
• Bioinformatics
• Computational biology

Related software

• WHAT IF software
• PROCHECK
• PSVS

External links

• Official website
• CheShift PyMOL plugin
• GitHub repository

References

1. Martin, O. A., Vila, J. A. and Scheraga, H. A. (2012). "CheShift-2: graphic validation of protein structures". Bioinformatics. doi:10.1093/bioinformatics/bts179.
2. Martin O.A. Arnautova Y.A. Icazatti A.A. Scheraga H.A. and Vila J.A. (2013). "A Physics-Based Method to Validate and Repair Flaws in Protein Structures". PNAS. doi:10.1073/pnas.1315525110.