Automated assignment of NOESY spectra is a prerequisite for automated structure determination of biological macromolecules. With the program KNOWNOE we present a novel, knowledge based approach to this problem. KNOWNOE is devised to work directly with the experimental spectra without interference of an expert. Besides making use of routines already implemented in AUREMOL, it contains as a central part a knowledge driven Bayesian algorithm for solving ambiguities in the NOE assignments. These ambiguities mainly arise from chemical shift degeneration which allows multiple assignments of cross peaks. Using a set of 326 protein NMR structures, statistical tables in the form of atom-pairwise volume probability distributions (VPDs) were derived. VPDs for all assignment possibilities relevant to the assignments of interproton NOEs were calculated. With these data for a given cross peak with N possible assignments Ai (i = 1,...,N) the conditional probabilities P(Ai, a/V0) can be calculated that the assignment Ai determines essentially all (a-times) of the cross peak volume V0. An assignment Ak with a probability P(Ak, a/V0) higher than 0.8 is transiently considered as unambiguously assigned. With a list of unambiguously assigned peaks a set of structures is calculated. These structures are used as input for a next cycle of iteration where a distance threshold Dmax is dynamically reduced. The program KNOWNOE was tested on NOESY spectra of a medium size protein, the cold shock protein (TmCsp) from Thermotoga maritima. The results show that a high quality structure of this protein can be obtained by automated assignment of NOESY spectra which is at least as good as the structure obtained from manual data evaluation.
Exclusively NOESY-based automated NMR assignment and structure determination of proteins
Exclusively NOESY-based automated NMR assignment and structure determination of proteins
Abstract A fully automated method is presented for determining NMR solution structures of proteins using exclusively NOESY spectra as input, obviating the need to measure any spectra only for obtaining resonance assignments but devoid of structural information. Applied to two small proteins, the approach yielded structures that coincided closely with conventionally determined structures.
Content Type Journal Article
Pages 1-10
DOI 10.1007/s10858-011-9502-8
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Exclusively NOESY-based automated NMR assignment and structure determination of proteins.
Exclusively NOESY-based automated NMR assignment and structure determination of proteins.
Exclusively NOESY-based automated NMR assignment and structure determination of proteins.
J Biomol NMR. 2011 Mar 30;
Authors: Ikeya T, Jee JG, Shigemitsu Y, Hamatsu J, Mishima M, Ito Y, Kainosho M, Güntert P
A fully automated method is presented for determining NMR solution structures of proteins using exclusively NOESY spectra as input, obviating the need to measure any spectra only for obtaining resonance assignments but devoid of structural information....
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Towards fully automated structure-based NMR resonance assignment of (15)n-labeled proteins from automatically picked peaks.
Towards fully automated structure-based NMR resonance assignment of (15)n-labeled proteins from automatically picked peaks.
Towards fully automated structure-based NMR resonance assignment of (15)n-labeled proteins from automatically picked peaks.
J Comput Biol. 2011 Mar;18(3):347-63
Authors: Jang R, Gao X, Li M
Abstract In NMR resonance assignment, an indispensable step in NMR protein studies, manually processed peaks from both N-labeled and C-labeled spectra are typically used as inputs. However, the use of homologous structures can allow...
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[NMR paper] Automated analysis of large sets of heteronuclear correlation spectra in NMR-based dr
Automated analysis of large sets of heteronuclear correlation spectra in NMR-based drug discovery.
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J Med Chem. 2002 Dec 19;45(26):5649-54
Authors: Damberg CS, Orekhov VY, Billeter M
Drug discovery procedures based on NMR typically require the analysis of thousands of NMR spectra. For example, in "SAR by NMR", two-dimensional NMR spectra are recorded for a target protein mixed with ligand candidates from a comprehensive library of...
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[NMR paper] The NOESY jigsaw: automated protein secondary structure and main-chain assignment fro
The NOESY jigsaw: automated protein secondary structure and main-chain assignment from sparse, unassigned NMR data.
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J Comput Biol. 2000;7(3-4):537-58
Authors: Bailey-Kellogg C, Widge A, Kelley JJ, Berardi MJ, Bushweller JH, Donald BR
High-throughput, data-directed computational protocols for Structural Genomics (or Proteomics) are required in order to evaluate the protein products of genes for structure and...
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[NMR paper] Application of neural networks to automated assignment of NMR spectra of proteins.
Application of neural networks to automated assignment of NMR spectra of proteins.
Related Articles Application of neural networks to automated assignment of NMR spectra of proteins.
J Biomol NMR. 1994 Jan;4(1):35-46
Authors: Hare BJ, Prestegard JH
Simulated neural networks are described which aid the assignment of protein NMR spectra. A network trained to recognize amino acid type from TOCSY data was trained on 148 assigned spin systems from E. coli acyl carrier proteins (ACPs) and tested on spin systems from spinach ACP, which has a 37%...
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[NMR paper] Application of neural networks to automated assignment of NMR spectra of proteins.
Application of neural networks to automated assignment of NMR spectra of proteins.
Related Articles Application of neural networks to automated assignment of NMR spectra of proteins.
J Biomol NMR. 1994 Jan;4(1):35-46
Authors: Hare BJ, Prestegard JH
Simulated neural networks are described which aid the assignment of protein NMR spectra. A network trained to recognize amino acid type from TOCSY data was trained on 148 assigned spin systems from E. coli acyl carrier proteins (ACPs) and tested on spin systems from spinach ACP, which has a 37%...
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Automated amino acid side-chain NMR assignment of proteins using 13C- and 15N-resolved 3D [1H,1H]-NOESY
Automated amino acid side-chain NMR assignment of proteins using 13C- and 15N-resolved 3D -NOESY
Francesco Fiorito, Torsten Herrmann, Fred F. Damberger and Kurt Wüthrich
Journal of Biomolecular NMR; 2008; 42(1); pp 23-33
Abstract
ASCAN is a new algorithm for automatic sequence-specific NMR assignment of amino acid side-chains in proteins, which uses as input the primary structure of the protein, chemical shift lists of 1HN, 15N, 13Cα, 13Cβ and possibly 1Hα from the previous polypeptide backbone assignment, and one or several 3D 13C- or 15N-resolved -NOESY spectra. ASCAN has also been...
Automated assignment of NOESY NMR spectra using a knowledge based method (KNOWNOE).
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