Automated peak picking

Keywords APSY Automated peak picking Automated resonance assignment GAPRO NMR Projection spectroscopy Protein backbone Protein side chains... 

On the basis of automated peak picking and integration procedure, after less than 2 h, the enantiomeric purity was established. R S ratio was 34.4 65.6, which is close to the values obtained from the 1H or 13C NMR spectra. 

The simplicity and clarity of CONCISE has been retained in the automated rule generator which creates CONCISE interpretation rules for PAIRS based on a representative set of IR spectra. The rule generator uses peak position, intensity, and width tables produced by an automated peak picking routine. This method reduces the dependency on published frequency correlation data and enhances the usefulness of data already available. All work was done using the version of PAIRS running on a Nicolet 1180 minicomputer and programs generated have been optimized for this system. 

Wiithrich et al published a tour de force on the Automated Peak-Picking and Peak Integration in Macromolecular Spectra (AUTOPSY). This work deals primarily with two-dimensional spectra, but the algorithms are equally... 

There are four general modes of operation for LC-NMR on-flow, direct stop-flow, time-sliced and loop collection/transfer. The mode selected will depend on the level and complexity of the analyte and also on the NMR information required. All modes of LC-NMR can be run under full automation for LC peak-picking, LC peak transfer to storage loops or NMR flow cell, and NMR detection [46],... 

In addition to providing automated peak picking and computation of the corresponding chemical shift lists, APSY supports automated sequential resonance assignment. Thus, APSY is a valid alternative to related NMR techniques. APSY can be the first step, after sample preparation, in a fully automated process of protein stmcture determination by NMR with successive automated algorithms for the NOESY spectrum analysis and structure calculation. 

Koradi R, Billeter M, Engeli M, Giintert P, Wiithrich K (1998) Automated peak picking and peak integration in macromolecular NMR spectra using AUTOPSY. J Magn Reson 135 288-297... 

The improved signal dispersion achieved due to the combined effects of H and S differentiation and the enhanced multiplet pattern simplification provided by both homo- and heteronuclear decoupling in both dimensions is also illustrated in Fig. 7. The H-15 methyl signal consists of two overlapped triplets where it is difficult to extract the exact chemical shift values in both H and conventional HSQC spectra. Note the superior performance of the SAPS approach for an automated peak picking to determine a more accurate and simultaneous determination of d( H), 5( C), AA5( H), and AAd( C) and to quantify each individual singlet signal by direct peak volume integration. 

Pure shift versions of the FI-HSQC and Fl-ilNEPT experiments have not been published but they are easy to design and implement with the aim to achieve automated peak picking and automated extraction of J(CH) and J(HH) couphng constants. 

The third of the three adjacent peaks (29.207 minutes) is readily identified as 2-hydroxybenzaldehyde (salicylaldehyde) by comparison of the MS or IR spectrum with library data. It should be noted that the automated search routine in the MS software picked 3-and 4-hydroxybenzaldehyde as better matches than the 2-hydroxy compound, even though the 76 ion in the spectrum of the unknown is present only in the mass spectrum of the 2-hydroxy compound. However, the IR search routine correctly identified the 2-isomer. This illustrates that casual operators who rely on automated search routines for compound identification are much less likely to make errors when they have access to both IR and MS searching. 

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