BIO NMR Services

Verification of screening hits and definition of binding locations

BIO NMR is the gold standard for sorting out binding behaviors. A 15N-labeled version of the protein is used so that only the protein is observed in the NMR spectrum. Solution conditions can be changed in real time and additions can be made while the status of each residue is monitored.

Upon addition of a potential binder, the protein response reveals whether the molecule binds, whether the interaction is clean, or whether the protein unfolds or aggregates. Based on the residues that respond, the binding location can be identified through footprinting.

For true binders, the footprint can immediately support docked ligand modeling and help guide chemistry optimization strategies. Equally important, lack of BIO NMR response reliably indicates non-binding.

• Essential for hit validation after screening campaigns
• Supports difficult targets such as protein-protein interactions
• Approximate protein requirement: 1–3 mg
• Approximate compound requirement: about 0.2 mg
• 15N labeling can be achieved in E. coli, yeast, or mammalian systems when needed

NMR screening of fragment libraries to obtain leads and Targeted Protein Degrader (TPD) ligands

BIO NMR can be used not only to examine molecules already identified as hits by other methods, but also as the primary detection method in a screen. Potential binders may be added as mixtures to increase throughput, and positive mixtures can then be deconvoluted to identify the true hit.

Because BIO NMR is highly sensitive, it can detect weak binding reliably and is therefore especially suited to fragment screening. While it may appear lower throughput at first glance, the combined detection and validation efficiency makes it highly competitive from screen to authentic lead.

Since chemical shift patterns are unique to every protein, multiple proteins can be screened together and the response can identify which protein the hit binds to. This can dramatically improve throughput or assess selectivity.

Elucidation of full detailed structures

BIO NMR can provide 3D structures of proteins, protein-ligand complexes, oligonucleotides, peptides, macrocycles, and TPDs. While many proteins and oligonucleotides can be studied by X-ray crystallography or cryogenic electron microscopy, some are not suitable for those approaches.

Because BIO NMR is performed in solution, it can also help resolve concerns regarding crystal packing effects. In many cases it can deliver medium-resolution information faster than other structural techniques.

Medium-sized macromolecules such as peptides, macrocycles, and TPDs often do not crystallize well, but can be studied effectively by BIO NMR. Detailed structures from these studies can guide the design of analogs that are more potent, stable, and bioavailable.

Application of advanced NMR methods to small molecules

The sophisticated NMR techniques used for macromolecules can also be applied to smaller molecules to answer demanding questions of structure and stereochemistry. BIO NMR approaches can provide rigorous verification of primary structure and deeper analytical confidence in complex molecular programs.