Design of an expression system for detecting folded protein domains and mapping macromolecular interactions by NMR

• Published in: Protein science Vol. 6; no. 11; pp. 2359 - 2364
• Main Authors: Huth, Jeffrey R., Bewley, Carole A., Clore, G. Marius, Gronenborn, Angela M., Jackson, Belinda M., Hinnebusch, Alan G.
• Format: Journal Article
• Language: English
• Published: Bristol Cold Spring Harbor Laboratory Press 01-11-1997
• Subjects: Bacterial Proteins - biosynthesis; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; DNA-Binding Proteins; domain structure; fas Receptor - biosynthesis; fas Receptor - chemistry; fas Receptor - genetics; Fungal Proteins - biosynthesis; Fungal Proteins - chemistry; Fungal Proteins - genetics; GBI‐fusion protein; Gene Expression; Genetic Vectors; High Mobility Group Proteins - biosynthesis; High Mobility Group Proteins - chemistry; High Mobility Group Proteins - genetics; intermolecular interactions; Nitrogen Isotopes; NMR; Nuclear Magnetic Resonance, Biomolecular - methods; Protein Conformation; Protein Folding; Protein Kinases - biosynthesis; Protein Kinases - chemistry; Protein Kinases - genetics; Recombinant Fusion Proteins - biosynthesis; Recombinant Fusion Proteins - chemistry; Research Design; Saccharomyces cerevisiae Proteins
• ISSN: 0961-8368; 1469-896X
• DOI: 10.1002/pro.5560061109

Two protein expression vectors have been designed for the preparation of NMR samples. The vectors encode the immunoglobulin‐binding domain of streptococcal protein G (GB1 domain) linked to the N‐terminus of the desired proteins. This fusion strategy takes advantage of the small size, stable fold, and high bacterial expression capability of the GB1 domain to allow direct NMR spectroscopic analysis of the fusion protein by 1H‐15N correlation spectroscopy. Using this system accelerates the initial assessment of protein NMR projects such that, in a matter of days, the solubility and stability of a protein can be determined. In addition, 15‐labeling of peptides and their testing for DNA binding are facilitated. Several examples are presented that demonstrate the usefulness of this technique for screening protein/DNA complexes, as well as for probing ligand‐receptor interactions, using 15N‐labeled GB1‐peptide fusions and unlabeled target.