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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
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RASP: rapid and robust backbone chemical shift assignments from protein structure
Christopher A MacRaild1, Raymond S Norton
1Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, 3052, Australia, chris.macraild@monash.edu.
Journal of Biomolecular NMR
|January 22, 2014
Summary
Resonance Assignment by chemical Shift Prediction (RASP) uses predicted chemical shifts to assign protein backbone resonances. This method efficiently assigns most residues, even for challenging proteins, accelerating structural analysis.
Area of Science:
- Biochemistry
- Structural Biology
- Computational Biology
Background:
- Protein backbone resonance assignment is crucial for structural determination.
- Conventional methods can be time-consuming and challenging for certain proteins.
- Chemical shift prediction offers a powerful, yet underutilized, approach for assignment.
Purpose of the Study:
- To introduce Resonance Assignment by chemical Shift Prediction (RASP), a novel method for protein backbone resonance assignment.
- To demonstrate RASP's effectiveness using predicted chemical shifts and structural information.
- To highlight RASP's potential to accelerate protein structure-based studies.
Main Methods:
- Development of the Resonance Assignment by chemical Shift Prediction (RASP) algorithm.
- Utilizing predicted protein chemical shifts derived from known structures.
- Employing data from sensitive triple-resonance experiments (HNCO, HNCA).
Main Results:
- RASP achieved 88% residue assignment accuracy at 99.7% for a dataset of 154 proteins.
- The method successfully assigned 90% of manually assigned residues in a 34 kDa protein using only 40% of experimental data.
- Robust assignments were obtained even for spectroscopically challenging proteins.
Conclusions:
- RASP significantly accelerates protein backbone resonance assignment.
- The method is particularly valuable for proteins with available structural information.
- RASP offers a feasible alternative for challenging proteins where conventional methods fail.
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