Abstract Nuclear magnetic resonance (NMR) and Mass Spectroscopy (MS) are the two most common spectroscopic analytical techniques employed in metabolomics. The large spectral datasets generated by NMR and MS are often analyzed using data reduction techniques like Principal Component Analysis (PCA). Although rapid, these methods are susceptible to solvent and matrix effects, high rates of false positives, lack of reproducibility and limited data transferability from one platform to the next. Given these limitations, a growing trend in both NMR and MS-based metabolomics is towards targeted profiling or â??quantitativeâ?? metabolomics, wherein compounds are identified and quantified via spectral fitting prior to any statistical analysis. Despite the obvious advantages of this method, targeted profiling is hindered by the time required to perform manual or computer-assisted spectral fitting. In an effort to increase data analysis throughput for NMR-based metabolomics, we have developed an automatic method for identifying and quantifying metabolites in one-dimensional (1D) proton NMR spectra. This new algorithm is capable of using carefully constructed reference spectra and optimizing thousands of variables to reconstruct experimental NMR spectra of biofluids using rules and concepts derived from physical chemistry and NMR theory. The automated profiling program has been tested against spectra of synthetic mixtures as well as biological spectra of urine, serum and cerebral spinal fluid (CSF). Our results indicate that the algorithm can correctly identify compounds with high fidelity in each biofluid sample (except for urine). Furthermore, the metabolite concentrations exhibit a very high correlation with both simulated and manually-detected values.
Content Type Journal Article
Pages 1-17
DOI 10.1007/s10858-011-9480-x
Authors
Pascal Mercier, Chenomx Inc, Edmonton, AB T5K 2J1, Canada
Michael J. Lewis, Chenomx Inc, Edmonton, AB T5K 2J1, Canada
David Chang, Chenomx Inc, Edmonton, AB T5K 2J1, Canada
David Baker, Pfizer Inc, Groton, CT USA
David S. Wishart, Department of Computing Science and Biological Sciences, University of Alberta, Edmonton, AB T6G 2E8, Canada
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
Abstract Four novel 5D (HACA(N)CONH, HNCOCACB, (HACA)CON(CA)CONH, (H)NCO(NCA)CONH), and one 6D ((H)NCO(N)CACONH) NMR pulse sequences are proposed. The new experiments employ non-uniform sampling that enables achieving high resolution in indirectly detected dimensions. The experiments facilitate resonance assignment of intrinsically disordered proteins. The novel pulse sequences were successfully tested using δ subunit (20 kDa) of Bacillus subtilis RNA polymerase...
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Suppression of sampling artefacts in high-resolution four-dimensional NMR spectra using Signal Separation Algorithm
Suppression of sampling artefacts in high-resolution four-dimensional NMR spectra using Signal Separation Algorithm
Publication year: 2011
Source: Journal of Magnetic Resonance, Available online 20 October 2011</br>
Jan*Stanek, Rafal*Augustyniak, Wiktor*Ko?mi?ski</br>
The development of non-uniform sampling (NUS) strategies permits to obtain high-dimensional spectra with increased resolution in significantly reduced experimental time. We extended a previously proposed signal separation algorithm (SSA) to process sparse four-dimensional NMR data. It is employed for two experiments...
[NMR paper] The three-dimensional high resolution structure of human interferon alpha-2a determin
The three-dimensional high resolution structure of human interferon alpha-2a determined by heteronuclear NMR spectroscopy in solution.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles The three-dimensional high resolution structure of human interferon alpha-2a determined by heteronuclear NMR spectroscopy in solution.
J Mol Biol. 1997 Dec 12;274(4):661-75
Authors: Klaus W, Gsell B, Labhardt AM, Wipf B, Senn H
The solution structure of recombinant human interferon...
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[NMR paper] Tools for the automated assignment of high-resolution three-dimensional protein NMR s
Tools for the automated assignment of high-resolution three-dimensional protein NMR spectra based on pattern recognition techniques.
Tools for the automated assignment of high-resolution three-dimensional protein NMR spectra based on pattern recognition techniques.
J Biomol NMR. 1997 Oct;10(3):207-19
Authors: Croft D, Kemmink J, Neidig KP, Oschkinat H
One of the major bottlenecks in the determination of proteinstructures by NMR is in the evaluation of the data produced by theexperiments. An important step in this process is assignment, where...
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NMR Metabolomic Profiling Reveals New Roles of SUMOylation in DNA Damage Response.
NMR Metabolomic Profiling Reveals New Roles of SUMOylation in DNA Damage Response.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-acspubs.jpg Related Articles NMR Metabolomic Profiling Reveals New Roles of SUMOylation in DNA Damage Response.
J Proteome Res. 2010 Aug 9;
Authors: Cano KE, Li YJ, Chen Y
Post-translational modifications by the Small Ubiquitin-like Modifier (SUMO) family of proteins have been established as critical events in the cellular response to a wide range of DNA damaging reagents and radiation;...