NMR in Biology: An Overview

Nuclear magnetic resonance spectroscopy (NMR) is a sophisticated research technique used to obtain detailed information about the structure, dynamics, reaction state, and chemical environment of molecules.

How NMR works

The principle behind NMR is that, in addition to being electrically charged, many nuclei also have spin. When such nuclei are exposed to an external magnetic field, energy transfers from the base energy level to a higher energy level. The reverse happens on removal of the magnetic field and energy is emitted at the same frequency as the energy that was absorbed.

Furthermore, the energy transfer takes place at a wavelength that corresponds to radio frequencies. Since the frequency depends on the intramolecular magnetic field around an atom, measuring the frequency can be used to determine the environment of atoms within the protein and the distance between nuclei, whereby a picture of the structure of a molecule is obtained.

The determination of structure from NMR is a highly technical multi-phase process. Interpretive approaches must be applied to find out which chemical shift corresponds to which nuclei in the spin system, then a structure is calculated based on known and experimentally determined properties of proteins.

Since the quality of the model achieved depends on both the quantity and quality of experimental data used to generate it and the correct interpretation of such data, it is also important that the structure is validated. Validation is essentially a check for errors and is based on established statistical and/or physics principles.

NMR: A Trend in Medical Research

NMR in biology

In biology, NMR is fundamental for determining and exploring the structure of proteins, e.g. enzymes, receptors. It has been used to elucidate the structure and function of numerous biological components. More recent discoveries include determination of the structure of the influenza virus proton transporter and the consequent development of molecules that block this transporter and stall infection by the virus.

Similarly determination of the structure of the CMAT receptor (an oncogene that is involved in cancer metastasis) has allowed a variant to be engineered that has an antagonistic effect. NMR thus plays a key role in the development of vaccines and treatments for a range of diseases, including HIV, influenza, tuberculosis and cancer, by allowing researchers to understand how the disease-causing agents function and to identify potential drug targets.

NMR also provides a powerful tool for studying conformational changes in proteins and chemical kinetic processes, which enables the mode of action of enzymes, transporter proteins etc to be elucidated at a molecular level. For example, it was discovered that dimerization is crucial for the ECAD protein to create adhesion between cells in multicellular organisms.

Similarly, NMR is being used to characterise the transition of proteins in the brain and to investigate the influence of such changes on neurodegenerative disease processes, such as Alzheimer's disease, Parkinson's disease, and Creutzfeldt-Jakob disease. Ultimately, such NMR studies may again lead to the development of tests and treatments for diseases in man.

Professor Michael Summers of The Howard Hughes Medical Institute explained:

NMR is the central tool we use... We've been able to learn a lot using NMR that I don't think you'd be able to learn using any other technology.
Avance III HD How Bruker provides the fastest, best performing and most flexible NMR research spectrometer on the market
Avance III HD How Bruker provides the fastest, best performing and most flexible NMR research spectrometer on the market.

NMR software

The level of detail provided by NMR has made it a fundamental tool for characterising the structure and function of proteins across many areas of research. However, NMR is a highly specialized technique and structure determination by NMR spectroscopy requires in-depth knowledge of chemistry and physics.

Recently, software has been developed (e.g. TopSolids™) making NMR accessible to a broad diversity of users. Furthermore, online NMR libraries are also available that can be searched to see if the sequence needed has already been determined so the measurements need not be repeated.

When conducting NMR it is important to obtain the best spectra possible (within the constraints of the experimental parameters). The key factors impacting the quality of the resultant data are sensitivity, resolution and the number of samples taken.

The development of non-uniform sampling (NUS) methodologies has allowed fewer samples to be taken without compromising resolution. Algorithms, such as NESTA, are used to estimate values for the missing points where measurements were not made. Such techniques allow structures to be determined more quickly and have demonstrated excellent performance sensitivity. However, it is still important to invest sufficient time in sampling to ensure the highest quality data.

The future of NMR

NMR is clearly a powerful tool in biological research, but researchers are still striving for greater sensitivity and resolution to broaden the scope of potential applications. Consequently, new NMR techniques are constantly being developed.

The latest advances (in addition to increased magnetic field strength) include refrigerated magnet technology that allows continuous NMR operation without the need for cryogen refilling, giving greater experiment flexibility and small-angle x-ray scattering (SAXS) NMR that provides more structural detail than NMR alone and can be performed using smaller samples.

Professor Arthur Palmer of Columbia University commented:

We need access to state-of-the art electronics, state-of-the art probes and state-of-the art magnets for everything we do...Each step to a higher and higher magnetic field has opened up new opportunities, and I think this is going to continue.

NMR spectroscopy is continually providing additional information that can be used by pharmaceutical researchers to develop treatments to prevent or combat a range of diseases, and technological advances continue to extend the boundary of capability of this already formidable technique.

About Bruker BioSpin - NMR, EPR and Imaging

Bruker BioSpin offers the world's most comprehensive range of NMR and EPR spectroscopy and preclinical research tools. Bruker BioSpin develops, manufactures and supplies technology to research establishments, commercial enterprises and multi-national corporations across countless industries and fields of expertise.


Sponsored Content Policy: News-Medical.net publishes articles and related content that may be derived from sources where we have existing commercial relationships, provided such content adds value to the core editorial ethos of News-Medical.Net which is to educate and inform site visitors interested in medical research, science, medical devices and treatments.

Last updated: Mar 11, 2022 at 12:13 AM

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Bruker BioSpin - NMR, EPR and Imaging. (2022, March 11). NMR in Biology: An Overview. News-Medical. Retrieved on October 04, 2024 from https://www.news-medical.net/whitepaper/20150121/NMR-in-biology-an-overview.aspx.

  • MLA

    Bruker BioSpin - NMR, EPR and Imaging. "NMR in Biology: An Overview". News-Medical. 04 October 2024. <https://www.news-medical.net/whitepaper/20150121/NMR-in-biology-an-overview.aspx>.

  • Chicago

    Bruker BioSpin - NMR, EPR and Imaging. "NMR in Biology: An Overview". News-Medical. https://www.news-medical.net/whitepaper/20150121/NMR-in-biology-an-overview.aspx. (accessed October 04, 2024).

  • Harvard

    Bruker BioSpin - NMR, EPR and Imaging. 2022. NMR in Biology: An Overview. News-Medical, viewed 04 October 2024, https://www.news-medical.net/whitepaper/20150121/NMR-in-biology-an-overview.aspx.

Other White Papers by this Supplier

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.