Rapid screening for structural integrity of expressed proteins by heteronuclear NMR spectroscopy.
A simple and rapid method based on 15N labeling and 1H-15N heteronuclear single quantum coherence spectroscopy is presented to directly assess the structural integrity of overexpressed proteins in crude Escherichia coli extracts without the need for any purification. The method is demonstrated using two different expression systems and two different proteins, the B1 immunoglobulin-binding domain of streptococcal protein G (56 residues) and human interleukin-1 beta (153 residues). It is shown that high quality 1H-15N correlation spectra, recorded in as little as 15 min and displaying only cross-peaks arising from the overexpressed protein of interest, can be obtained from crude E. coli extracts.
Gronenborn
A M
AM
Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA. gronenborn@vger.niddk.nih.gov or clore@vger.niddk.nih.gov
Clore
G M
GM
D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D009587:Nitrogen Isotopes; D011522:Protons; D011994:Recombinant Proteins / Q000737:chemistry* / Q000235:genetics
D009587:Nitrogen Isotopes; D011522:Protons; D011994:Recombinant Proteins