Isotopically Enriched Components for Biomolecular NMR
An important tool for high-resolution structure determination for NMR spectroscopy is the use of stable isotopically labeled biomolecules. By either selectively or uniformly incorporating stable isotopes into proteins, the user is able to significantly reduce the complexity of their spectra. 13C, 15N, and deuterium are the most common isotopes incorporated into proteins. Microbial expression systems, cell-free extracts, peptide synthesis and custom synthesis provide a variety of options for accomplishing the incorporation of the labels. Microbial expression systems are cell-based protein expression systems in which the microbes are grown in either a defined or complex media with 13C labeled glucoses and 15N labeled ammonium salts as the sole sources of carbon and nitrogen respectively. Ease of use, adaptability and high protein yields have made these expression systems the most popular technique for stable isotope incorporation. Cell-free extracts and custom synthesis also present their own individual advantages with the use of uniformly or selectively labeled amino acids. Cell-free extracts allow the user to more readily implement high-throughput in vitro protein expression as many proteins are difficult to express in vivo due to complications such as toxicity. Custom synthesis allows for unique, site-specific incorporation of isotopes into peptides allowing the user to study distinct structural regions.
ISOTEC Stable Isotopes is devoted to aiding in the advancement of these studies by providing the NMR community with a broad product line. Minimal media components and ISOGRO, a complex growth medium, are available for protein expression systems, while a complete line of fully labeled amino acids are available for cell-free synthesis applications. If a custom product is required, our custom synthesis team is able to assist in the design of your biomolecule of interest. Contact Us for any questions, request a quote or to place an order.